From lemons and limes to oranges and mandarins, citrus are a must-have addition to any Kiwi backyard, and can be grown successfully in the garden or in pots.
We often get asked for growing advice and suggestions on treating problems on citrus, so we have put together answers to your most common questions.
Q.
Hi, we are growing about 10 different citrus including oranges. The oranges all seem to be quite sour. I have sprinkled Epsom salts around - is that going to be enough to help? Also, how can I stop the fruit and leaves getting black scum on them? Thanks, Leah.
A.
The black scum is sooty mould, there will be insects – aphids, scale, mealy bug on the tree. Spray (with warm soapy water, or check at your local garden centre for a suitable spray) to control the insects and the sooty mould will go away. Sweetness of oranges can be affected by a variety of factors including climate (needs some warmth to sweeten), variety (some being more sour than others), ripeness (try leaving them on the tree a bit longer). To help grow successful oranges make sure you feed them in spring and summer with Tui Citrus Food and keep them well watered. Add a layer of mulch around the base of the plant too.
Q.
Hi, my lemon tree has plenty of lemons on it but no leaves. What could be causing this? Thanks, Amy.
A.
Citrus are evergreen but do drop leaves, usually when they are stressed, too cold, have too much fertiliser, or not enough fertiliser, if there’s frost, or they are too wet. I would suggest regular doses of Tui Organic Seaweed Plant Tonic every seven days until the tree starts bursting into leaf. Give it regular feedings in spring and summer when temperatures warm up. Don't feed it in winter as the tree isn't actively growing. Try adding sheep pellets to nourish the soil and mulch around the tree so it doesn't dry out in summer. If it is in a pot and become pot bound it might need re-potting.
Q.
I have several citrus trees. I've been told that in the first year of fruiting, I should remove all the fruit from the tree. In the second year, I should remove half of all the fruit from the tree (when it is the size of a 20c piece), and in the 3rd year I should remove 1/3 of the fruit. Is this good advice? Thank you, Caroline.
A.
It’s definitely a good idea to remove the fruitlets off the tree in the first year. The subsequent years, the rule of thumb you noted is a good idea in theory, but it does depend a lot on the health, strength, size and type of tree. In general terms of fruit thinning, you want to remove a portion of the crop so that when the fruit is mature, each fruit is not touching the next (as this can cause blemishes and disease problems). You also need to take into account the weight of the fruit on the branches, so that the mature fruit will not cause breakages. So after the first year, it really is a judgement call as to how well the tree is establishing, how heavy the crop is and how much the tree can handle.
Q.
I moved house and the place we are in now has a mandarin tree. The mandarins are tiny, what can I do to make them grow bigger? Thank you, Joanne.
A.
Mandarins are wonderful fruits. For the crop this year there is nothing you can do to remedy the problem. In the spring, give the plant a side dressing of citrus food and add a layer of mulch all around the base of the plant. This will feed the plant and keep the root zone moist. Over summer keep the plant well watered, small fruit indicate poor watering over the summer when the fruit develops. An application of Tui Organic Seaweed Plant Tonic now will give the plant a boost, but avoid adding the fertiliser too early as young growth may get frosted.
Q.
Hi, I got a lemon tree a few months ago. Its leaves are curling and dull. I've given it citrus food and haven't noticed a change. What do you recommend? April.
A.
Citrus leaves will curl when temperatures are cold or in extreme heat, some insect infestations such as scale, mealy bug, mites or aphids will cause leaves to curl or over-watering. We have had unseasonably cold weather.
Adjust watering depending upon the weather. Feed it Tui Organic Seaweed Plant Tonic plant tonic regularly, keep it well watered if it is heat, or just give it Organic Seaweed Plant Tonic regularly if cold and watch the watering, don’t over-water it. Feed with Tui Enrich Fruit, Citrus, Tree & Shrub controlled release fertiliser (suitable for containers) in early spring and late summer. In frost prone areas avoid feeding any later than mid February as this will push soft new growth that will frost easily and won’t have had time to harden off.
If it is an insect problem control common insect pests by spraying warm soapy water, or check at your local garden centre for a suitable spray. If ants are crawling up the tree then there is a good chance there is scale insect or mealy bug or aphids.
Q.
Why is citrus food not suitable for use in containers? Thanks, Margaret
A.
We generally don't recommend using our Food range (including Tui Citrus Food) in pots and containers because it is not a slow release fertiliser and can overfeed in a smaller space e.g. pot or container, especially if not applied in the correct amount. This will then affect the plant. We recommend a controlled release fertiliser such as Tui Enrich Fruit, Citrus, Tree & Shrub controlled release fertiliser for use in pots and containers.
Q.
My lemon tree has heaps of lemons which don't have any juice. Do you know why this is? Thanks, Pauline.
A.
Dry lemons are normally caused through lack of water over the summer period as the fruit is forming. You can't get the moisture into your current seasons lemons but you can fix the problem so it doesn't happen next year, by watering more regularly. It can also be caused by lack of fertiliser. Now is the right time to apply Tui Citrus Food around the base of the plant then again at the end of fruiting, add a layer of mulch around the base of the plants after you fertilise to help the soil retain moisture. For citrus in containers, we recommend using Tui Enrich Fruit, Citrus, Tree & Shrub controlled release fertiliser.
Q.
Hi, can you tell me why my limes keep dropping off my tree. I get loads of flowers and most of them start to form little limes and then all of a sudden I lose most of them. I water every second day and also feed it. I am growing it in a large pot. Pam.
A.
Fruit drop is caused by stress – water (too much or too little), temperature (hot/cold extremes), nutrition problems and/or pest/disease problems. Some things to consider:
- How long as the tree been in the pot? It may need repotting, to replenish the growing media as it can become ‘hydrophobic’ – which means the mix actually repels water. Use good quality mix like Tui Pot Power.
- Have you fed the tree enough? For citrus in pots you need to take care to use a suitable fertiliser. Citrus are heavy feeders so need very regular fertiliser to keep the leaves dark green and glossy (no yellowing, curling or discoloured veins), with lots of new growth and fruit production. Use Tui Enrich Fruit, Citrus, Tree & Shrub controlled release fertiliser for citrus in pots, or Tui Citrus Food for trees planted in the ground.
- Are you watering deeply enough? There should be enough water applied that it leaks steadily from the drainage holes in the pot, so that the growing media is well drenched. Check the moisture levels on the day you don’t normally water by poking your finger down into the dirt. If it’s damp it doesn’t need more watering that day, but if it’s dry, you may need to move to daily watering.
- Is the tree exposed to cold snaps? Cover with protective cloth or move into a warm area if unseasonal cold spells/nights are expected.
Q.
The leaves are turning yellow on my mandarin tree. I have tried feeding with citrus food and worm castings, do you have any other ideas. Thanks, Jacqualine
A.
If magnesium is deficient then the leaves will turn yellow. Your tree will benefit from a dose of Epsom salts which is magnesium. Use Tui Epsom Salts. Also make sure your tree is free from weeds which will compete for water and nutrients and mulch around it to help conserve soil moisture as well as keeping weeds down.
Q.
Hello, I have a lemon tree that has lots of fruit but the leaves are covered in yellowish nodules and they are crumpling up. The fruit is flavoursome but the outer skin is looking like a case of tiny acne with thin brown lines. What do you recommend? Thanks, Rachel.
A.
The lumpy fruit and distorted foliage is caused by a fungus disease called verrucosis. It is prevalent in citrus and by spraying the tree when it has finished flowering with copper oxychloride until it starts to bud and flower will help prevent the disease.
The damage caused by verucosis is largely cosmetic. The fruit flavour is fine, and the fruit usually juicy. As the disease distorts the foliage there is reduced plant vigour but it generally doesn’t kill a plant. Regular feeding with Tui Citrus Food, watering and mulching will help the tree become more resistant to pests and diseases. Regular applications of Tui Organic Seaweed Plant Tonic will also be beneficial to your tree.
Q.
Just wondered if you have a nice way to get rid of the ants on my citrus trees but not disturb other insects like the bees! Thanks Maureen
A.
Fortunately, the ants do not harm the fruit, they are there because there will be an insect exuding a honey dew such as scale, aphids, or mealy bug. By controlling these insects you should not attract ants. Check at your local garden centre for a suitable spray - there are natural options available.
Q.
We have an orange tree in our backyard but the oranges never ripen properly, they never turn orange and when cut open they are pretty well tasteless and mushy. What could be the cause of this please?
A.
Oranges require a long warm summer and mild winter to fruit successfully. If your climate is right, the most likely reasons for the lack of fruit is the plant isn't getting enough nutrients from the soil. Fertilise in spring and summer with Tui Citrus Food. It would also be useful to prune back your orange tree to encourage some new growth and fruiting wood. The more air movement and sunlight the plant can get the more likely the fruit will ripen. Water frequently in summer as this is when the fruit is developing its flavour and size.
Q.
Hi, my lemon tree is looking lovely and lush with green leaves and new growth after giving it a dose of citrus food. It's two years old and had two blossoms when I bought it. Once planted, the fruit dropped off when they were only about 1cm long, and it hasn't blossomed since. Do you know why? Thanks, Vicky
A.
As the plant is only two years old it is not a problem that it is not flowering as it is good for the tree to spend energy in establishing its roots first. We suggest feeding with Tui Citrus Food or Tui Enrich Fruit, Citrus, Tree & Shrub controlled release fertiliser in early spring and late summer to assist with flowering.
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All your citrus questions answered Comments
We purchased a very run down property 10 yrs ago.we rescued an old persimmon tree amongst tall black bamboo n wonder if we can expect fruit. Have had acorn sized green fruit that just drops down. A nice shape to it though.
Ethel Campbell
I tasted a lovely sweet grapefruit with an orange skin grown in the Bay of Plenty, would you know the name? thanks
Maree
Hi Maree, unfortunately it is hard to be sure without seeing the actual fruit. Do you have a photo? Have a look here: https://www.waimeanurseries.co.nz/our-products/fruit-trees/citrus/ Thanks, Tui Team.
jenna
Our lemon tree was planted 18 months ago - it has grown quickly to over 2 metres, looks healthy but isn't producing blossom or fruit. Is this a good thing?
Fay Burnett
My established mandarin tree grows very small tight fruits which drop to the ground and a generally unedible as they are too small and not mature enough and ripened. I must admit I don't water it very often or probably feed it enough.
Nicky Hawker
Hi Nicky, watering and feeding are key. In the spring, give the plant a side dressing of citrus food and add a layer of mulch around the base of the plant (without touching the stem). This will feed the plant and keep the root zone moist. Over summer keep the plant well watered, small fruit indicate poor watering over the summer when the fruit develops. Fruit drop is caused by stress – water (too much or too little), temperature (hot/cold extremes), nutrition problems and/or pest/disease problems. An appication of Seasol plant tonic will give the plant a boost, but avoid adding the citrus fertiliser too early as young growth may get frosted. All the best, Tui Team
jenna
Hi Fay, it is a good sign your tree is looking healthy. Citrus trees take 1-2 years to fruit after planting. Have you fed your tree in spring and summer? All fruit trees benefit from a regular feeding regime to provide the right nutrients for maximum tree health and top crops. Feed with Tui Citrus Food in spring and summer. Mulch around the base of the tree and water well over summer. All the best, Tui Team
jenna
Hi, my yen-ben is about 3 years old. Has lots of fruit but very small and it never matures. We have been feeding all the right stuff and spraying Tui spray for mites etc., Can you help please. Joan
Joan
I grow some caffir lime trees in the pots and changed the soil with potting mix and compost a few months ago. Two of them had fruit but only small and the others didn't. One has slight yellow leaves. Is it better to grow them in the ground rather than in the pots? How do you make them bear a lot of fruit? They've been in the same size of pots for many years.
Robbie
Hi Joan, it sounds like you are looking after your tree well. Over summer keep the plant well watered, small fruit indicate poor watering over the summer when the fruit develops. An application now with Seasol plant tonic will also give the plant a boost, avoid adding any more fertiliser now as young growth may get frosted. Thanks, Tui Team
jenna
Hi Ethel, persimmon trees are normally rather robust and hardy fruits. Suggest yours probably needs some TLC to bring it back to a fruiting stage. Firstly apply Seasol plant tonic once a month for the rest of the year, fertilise it now with fruit fertiliser and add a layer of mulch around the base of the plant to protect the roots. The tree will soon be going into a dormant state; however the roots will be still active, so action will make a difference and should mean a harvest for next year. Keep up with watering over summer also. All the best. Thanks, Tui Team
jenna
If your tree has grown to 2m in 2 years, take the top out and perhaps reduce the nitrogen, or a little extra potash. Cheers
ArnieMason
Hi, Our orange tree has lots of lovely big fruit but some of the fruit have split open.Can you please help?
Margaret Spence
Hi, I have moved about a year ago into a new house which has a lemon tree. It looks healthy enough and has lots of good sized green fruit on it but they just don't seem to be ripening. Am I being too impatient or is there something I should be doing?
Sarah
Hi Sarah, it is a good sign your tree is looking healthy and has fruited. The citrus harvest season is just beginning so they still have plenty of time to ripen. We suggest feeding in spring, summer and early autumn (in late autumn there is risk of frost so we don't advise feeding now) with Tui Citrus Food to help promote healthy growth and fruiting. An application of Seasol plant tonic now will give the tree a good boost, and you can apply this every few weeks. All the best, Tui Team.
jenna
Hi Margaret, this can be a problem if the plant has had too much fertiliser and a lot of water for extended periods. Whilst both are good for the plant, it can cause the fruit to grow really quickly and split. Thanks, Tui Team
jenna
Hi Robbie, kaffir lime trees are very happy growing in tubs and planters, over time the root zone can get restricted so it is wise every few seasons to re-pot them into larger tubs. Kaffir limes do not produce a lot of fruit; they are mostly grown for their foliage which is used in Asian cooking. Apply Seasol plant tonic to give them a boost and trim back any long branches to encourage some more new growth and fruiting wood. All the best, Tui Team
jenna
Hi Robbie, we are delighted to inform you that your question has been chosen to feature in our newsletter. Please email your address details to info@tuiproducts.co.nz and we will post your prize out :) Enjoy, Tui Team
jenna
hi there. I have to grow my lemon tree in a pot so I can have it in the sun much of the day. otherwise it would get minimal especially in the winter season. how do they cope with repotting when the time comes? I have heard they don't do good to be removed. is there some good tips I can follow when the time comes? thanks adrienne
adrienne
Hi Adrienne, how big is your tree? The bigger the tree the harder it can be to transplant successfully. The best time to repot would be winter. When repotting we suggest: taking it out of the tub, trimming the roots and soaking the root ball in a bucket of Seasol plant tonic. Seasol will help reduce transplant shock. You can keep applying Seasol every couple of weeks to give the tree a good overall boost. Repot into a quality mix like Tui Pot Power as it has all the goodies your tree will need in its new pot. All the best, Tui Team
jenna
I live in Christchurch close by Riccarton Bush.I have a massive lemon tree.Can I grow a lime tree on my property.Thanking you in anticipation.
John
Why does my lemon tree have healthy green leaves but no fruit?
Pauline
Hi I have just transplanted a Mandarin tree from one side of town to my place it is about 1.5 mtrs high. The leaves are wilting and going brown. I don't know if it's to far gone but is there anything I can do to help it or am I best to try again with a younger tree. Thanks Shaun.
Shaun
Hi Pauline, that's a great sign your lemon tree has healthy green leaves. It sounds like the tree has too much nitrogen in the soil which means lots of leaf growth. If your tree is planted in the garden we suggest an application of Tui Sulphate of Potash to help encourage flowering. Feed citrus planted in the garden in spring and summer with Tui Citrus Food. For citrus planted in pots and containers feed with Tui NovaTec premium. Happy gardening from the Tui Team
jenna
Hi John, yes you can grow limes in Riccarton. The best one for Christchurch is the Tahitian lime. You will find them in all the shops now, get it planted in soon so it can get well established before next winter. You may need to protect it from frost over the first year or two. Remember full sun is preferred. All the best, Tui Team
jenna
Hi Shaun, citrus do transplant well when they are smaller. Suggest you trim the plant back by half, this will help save the plant trying to support excess growth. Apply Seasol plant tonic once a month for 6 months and add citrus fertiliser around the drip line of the tree. Keep the watering up over the hottest months. All the best, Tui Team
jenna
I am a new citrus gardener and I have potted Satsuma and Tahitian Lime which I feed with citrus food every two months - I notice that you recommend Seasol as well. What is the correct ratio of feeding if using both products? Have had an infestation of Hopper Vine insects which I have used a natural pyrethrum spray. Have also noticed a few tiny black beetles. Will the pyrethrum control both of these. Also, the Satsuma is developing some spiky lumps on the green fruit. What do I need to treat this with. Many thanks.
Wendy Faith
Hi Wendy, thanks for getting in touch. It is not best practice to use Citrus Food on citrus growing in pots and containers as it can be too concentrated and could burn the plant roots. Use a slow release fertiliser such as Tui Novatec every three months in the growing season or Scotts Osmocote Citrus Controlled Release fertiliser every six months. Tui Seaweed Plant Tonic or Seasol and can be used weekly, fortnightly or monthly mixed in a watering can at a rate of 30-70ml per 9L of water. This is a plant tonic, not a fertiliser so it can be used regularly. Passionvine hopper is very hard to control, pyrethrum is the best spray to use but not safe for bees if the citrus is in flower so if using, spray early in the morning or late in the afternoon when bees are not flying, Pyrethrum won’t control the beetles. Using seaweed plant tonic will strengthen the plants and help the plant build up resistance to pest and disease. If the citrus are well fed, regularly watered, in the right position and the right size pot they should flourish. All the best ^Tui Team
jenna
My lime tree has recently started to have the leaves curl up from the edges in large parts and some are curling and being eaten it looks like but I can’t find any bugs. I have pics I can show if anyone can help
JJ
Hi. We've just bought a place up in the hills in Oropi, Bay of Plenty. I expect we are going to have plenty of frosty mornings here and I'm not sure of where to plant the lemon and orange trees I was given. It's a very hilly property and my choices are up on the windy exposed ridge or on a slope in one of the little valleys. The valleys will be more protected from the very strong winds we get here but won't get as much sun and will make picking fruit difficult. Do you have any suggestions? Should I cover the trees in frost cloth? Many thanks Deanne
Deanne
Hi Deanne, we would suggest leaving the citrus in pots until spring when they have been through a winter so you know exactly where the frost is, how hard the frosts are and how little sun the valley gets. The valley doesn’t sound ideal if picking will be a problem, unless you cut into the bank and create a flat planting space. This will make watering, feeding and picking much easier but you still need to see how frosty and how shaded it is. Planting a hedge or putting up some shelter to protect the citrus from the prevailing wind is something that can be done now. As far as covering the trees with frost cloth, you need to see how severe the frosts are. Look at the neighbours place (if they are close by) and see what they have planted and where. Happy gardening ^Tui Team
jenna
Hi I have several orange trees (Navel and Washington I think), which are probably 6 or 7 years old and produce fruit. However the fruit never seems to ripen fully (i.e. the skin doesn't go orange). Any ideas/recommendations? Thanks Ngaire
Ngaire Phillips
Hi We moved into our house last July and bothered mandarin and lemon tree have been fruiting almost constantly. Both need trimming as they’ve grown a lot both up and out and the lemon tree now has branches in the ground but I read somewhere that if fruiting or flowering pruning can lead to some disease. Is this correct? When is the best time time to prune? Thanks
Nicola
Hi I have a very old lemon tree that has "moss" on the branches and is spindly in growth. How can I clean it up to get healthy growth and produce well Many thanks
Helen
Ata marie, I have a a mandarin tree with abnormally very large mandarins on it and there is only about 8 mandarins on the tree. The tree is approx 4 foot tall and 3 foot wide. During the summer season i gave the tree citrus food, fresh shelled kina juice whenever i went diving, copious amounts of water, some epson salts sprinkled around the drip line, blood and bone, i pruned the centre out, the garden itself has a 4 inch layer of bark also. The tree lives next to 2 feijoa trees and I'm in Hastings. I haven't opened a fruit yet as they are still green but I'm concerned as the last 2 years it gave us normal fruit with ample supply. Any advice will be much appreciated. Thank you. Steve
Steve
Hi Nicola this is a great question. The best time to prune citrus is in early summer or early autumn, so you will need to wait. Avoid pruning in September/October as you run the risk of lemon tree borer laying eggs in the fresh cuts. You can prune them back quite hard, up to a third is fine. Protect cuts with pruning paste or water based paint to seal the wound. Fertilise with Tui Citrus Food in spring and regularly apply Tui Organic Seaweed Plant Tonic for an overall boost. All the best ^Tui Team
jenna
Hi Helen, you can use the hose or a soft water blaster to remove the moss from your tree, once it is removed, spray with a copper spray (check at your local garden centre) to eliminate anything remaining. Next apply a side dressing of citrus fertiliser and regularly apply Tui Organic Seaweed Plant Tonic. Trim back the spindly stems in early summer, to stimulate healthy new growth. All the best ^Tui Team
jenna
Hi Ngaire, some oranges do not actually go fully orange when they are ripe. If you have little or no juice in your fruit the soil could be lacking some essential nutrients. Apply citrus fertiliser around the base of the tree. Regular applications of Tui Organic Seaweed Plant Tonic will also help. Navel oranges take about 6 to 7 months to ripen, and they require plenty of sunlight. Pruning in early summer may be required to let more light into the tree. All the best ^Tui Team
jenna
Hi Steve, you are being very kind to your mandarin tree. Once a tree has been pruned it can take up to two seasons for it to produce more flowering and fruiting wood, so it may be a case of being patient. Suggest you hold off adding any more nutrient based items to the root zone of your tree until mid-spring. Fruit can take up to 6 months to ripen. Hope this information helps. Happy gardening ^Tui Team
jenna
Hi there, we planted a satsuma mandarin a few months ago (dug big hole, filled with nice soil and compost). He's well sheltered, has grown a little and looks healthy, currently fed with a little bit of citrus food every couple of months. At the moment he's just one stick with leaves, how can we encourage him to branch out more?
Aaron
Hi Aaron, citrus are slow growing plants. Allow the plant at least six months to settle in, over winter do not expect a lot of growth, and if you live in a cold area, protect your plant from frost. All the best ^Tui Team
jenna
Hi There, i've planted a sasuma mandarin tree about three months ago under a metre high with green mandarins already growing on it and starting to colour - as they aren't buds, should I still be picking them off the tree? Thanks Jen
Jen
Hi Jen, great to hear you have planted your own mandarin tree. In the first year after planting your citrus, we suggest you remove any fruit that sets. This allows the tree to establish itself and encourages better fruiting in the following seasons. Happy gardening ^Tui Team
jenna
I've picked an orange off our tree and it's a lovely orange but has a caterpillar or worm in it.. what should I have sprayed with to prevent this ?
Marlene
Hi Marlene, this is such a shame isn’t it! The worm is most likely a larva of some type of insect, and depending on what it is, depends on what to use to control it. It is likely the eggs were laid in summer or autumn when the adult moth or fruit fly was active, and the worm has burrowed into the fruit to over winter. There is little you can do now unfortunately. Next summer keep an eye out for insects and spray then with a suitable spray if required. All the best, Jenna ^Tui Team
jenna
Our lemon tree has had a hard life. It has been noved several times. But for the last 15 years it has produced many many juicy flavoursome lemons. This year I noticed the fruit was takibg a long time to ripen and are smaller than usual. Now I see most of the bark is stripped off from the ground up for about 6 inches. Any clues on what we can do to save it. It looks tragic! Thanks in advance
Geoff
Hi Geoff, sorry to say the diagnosis for your lemon tree isn’t looking good. Now it has been ringbarked it is unlikely it will recover. Suggest letting it see out its life, until it finally turns up its toes. You can keep up with feeding and applications of Tui Organic Seaweed Plant Tonic, however once it has been ring barked, not a lot can be done to remedy the situation which was more than likely caused by a hungry possum. All the best ^Tui Team
jenna
I know I'm supposed to stop feeding my citrus in the winter, however, when I've tried to slow/ween the fertiliser, my citrus trees turn yellow very quickly. Should this be happening? They're dwarf varieties in 60L pots.
Toni
Hi Toni, only stop feeding your citrus through winter if you are in a frost prone area. If you are frost free, feed every 3 months with Tui NovaTec or Tui Enrich Fruit, Citrus, Tree & Shrub fertiliser, both are great for citrus in pots. In winter the leaves will yellow, reduce your watering when temperatures cool down as well. I like to sprinkle Tui Mini Sheep Pellets around my citrus in pots – they are a smaller pellet and can be applied around pots and are a good slow release source of nitrogen.
Tui Team
Hi there, what's the most reliable way to get rid of blackberry? We thought we'd removed it and then sprayed it with weed killer. A few months later we returned to the section and it is now growing in patches all over the place. Do we need to dig it out?
Te Rina
Hi Te Rina, spraying is the most effective way to rid areas of blackberry. They have runners or stolons that creep undergrown and are the ultimate survivors. Continue spot spraying with a weedkiller to control tough weeds (check at your local centre). A systemic weed control product for hard to control weeds is best for blackberry, the more it establishes and the bigger it gets the harder it is to control.
Tui Team
Hi team. Which mandarin grow best in chch? Does it do well in a pot? Thx
Fee
Hi Fee, great question. Clementine is a variety commonly grown in NZ that is suited to cooler growing conditions and has a low heat requirement. It also grows well in pots and containers. You could also check at your local garden centre for other varieties available that will be suitable for your region. Happy growing!
Tui Team
Hi, I have a mandarin tree now 4 years old and quite small. So far we haven't had any fruit on it although a few flowers. I feed it regularly and it is near a lime tree. Is there any obvious reason it isn't fruiting yet?
Nikki
Hi Nikki, no other than where is it planted, is it getting enough sun? Maybe it needs an extra boost with potassium (potash). Apply Tui Sulphate of Potash, it can be mixed in a watering can and applied or around the dripline of the tree. The other thing you can do is to scrape up some leaf litter from around an established fruiting citrus tree and place it around your mandarin. There is a mycorrhiza (beneficial soil microbes) that live in the soil that benefits citrus and enhance fruiting.
Tui Team
Hello, I have a little problem. Whenever I move my citrus tree to direct sunlight, the top leaves become soft and curl. Why is that?
Jakob
Hi Jakob, the tree is showing signs of stress. It could be that the new growth needs to harden off or the tree needs more water than it is being given at the moment. Water your citrus until the water drains out of the pot. In summer this could be daily, in winter once a week depending on the weather. Also give your citrus a regular application of Tui Organic Seaweed Plant Tonic every 2-4 weeks at a rate of 70ml per 9L watering can.
Tui Team
My lemon tree is very unwell. It has leaf drop and large brown marks in the leaves which seem to increase in size. I have fed it and sprayed with conquero oil. It has been very wet here.
Juliet Clarke
Hi Juliet, this sounds like poor drainage if the leaves have large brown circular rings, and this is caused by a fungal disease. Is the tree planted in free draining soil? Citrus don’t like wet feet which can happen in heavy clay soils. Are you able to improve the drainage? Re-planting the tree into a raised bed might help to do this. Conqueror oil is for insects and won’t help a fungal disease. Your local garden centre can recommend a spray, but to stop it happening the drainage will need to be improved.
Tui Team
My wife and I are in Nicaragua and just now learning if the benefits of citrus leaf tea. What is the best way to sustainably harvest the leaves of citrus fruit trees without harming the fruit growing potential?
Steven
Hi Steven, don’t pick all of the leaves, leave some of the branches to flower and form fruit. By harvesting the new leaves you will be reducing the chance of fruiting. The more you pick the more this will stimulate new leaves and growth. You will need to sacrifice some trees and leave them to fruit if you want citrus fruit as well.
Tui Team
Hi Tui, my lemon tree is growing what looks like oranges. They taste sour and bitter. What should I do to turn the fruit back to lemons?
Cristina
Hi Cristina, that is likely to be the rootstock that has taken over, which can sometimes happen if the tree has been pruned back severely. There will be vigorous shoots coming from the base of the tree that may look different to the lemon tree foliage. To get the lemon back you will need to remove the (orange) rootstock suckers as they will dominate the lemon because it is vigorous.
Tui Team
Hello Tui. My passion fruit vine has started to flower. This seems like an odd time of year for flowers to develop. Why is this happening ?
Sarah
Hi Sarah, it has been an unseasonably warm autumn and the weather hasn't really turned cold yet, many plants are flowering out of season. As soon as temperatures drop flowering will stop, the fruit is unlikely to amount to anything, pick any fruit that set off the vine.
Tui Team
Can an established kaffir lime tree be dug up from a garden and potted up into a pot? How should it be done? What would it’s chances of survival be? Thank you.
Di Barr
Hi Di,
There is no mention of how big the tree is, but you can transplant a kaffir lime tree, success will depend upon how well established the tree is. June/July is a good time to transplant anything in the garden. Before moving the tree it is a good idea to go around the dripline of the tree to a spade depth - this is called wrenching. Leave the tree for at least two weeks, it will start producing new roots and this will hopefully help reduce transplant shock. Also start applying Tui Seaweed Plant Tonic to the tree weekly until it gets shifted, to help reduce transplant shock. Continue feeding the tree with seaweed once it is in its new pot to help it get established, seaweed helps stimulate new root growth. Use a quality potting mix such as Tui Citrus & Fruit mix which is specially formulated for growing citrus in pots. It isn't a good idea to use garden soil or compost in pots as this compacts down and eventually starves the roots of air and fertiliser, compost and soil isn't as well draining as potting mix either. Trim the tree back by approximately a third, this will help stop foliage from wilting when it is transplanted, it is best to do this on a dry day and it can be trimmed back before shifting. Good luck, The Tui Team.
Tui Team
we'd like our citrus, orange and lemons, to ripen three months earlier or later. They now are ready for picking in July. We'd like to do whatever we can to have them ready to pick in October. How?
ron Keenberg
Hi Ced, the best time to prune apricot trees is in summer after fruiting has finished to reduce the chance of disease affecting the tree. Shorten limbs by about a third, you want to aim for an open vase (V) shape so that light can get in and ripen fruit. Shorten weak shoots by a third, remove branches that criss-cross through the centre, dead wood, remove vigorous growth and reduce water shoots (vigorous shoots that grow straight up). Fruit forms on spurs from the previous seasons growth which is wood that is 2-3 years old. The fruiting spurs fruit for 3-4 years. Paint all wounds with a pruning paste or water based paint. The Tui Team.
Tui Team
Hi Tui, I have a citrus tree that is about five years old. This year it produced several hundred oranges. The top oranges were quite large and had some dry areas in them, the oranges in the middle of the tree were average size and tasted good and were juicy, and finally the oranges in the bottom of the tree were quite small and full of juice and very sweet. Can you tell my what is going on with my orange tree?
Tanya
Hi Tanya, there are several reasons why your fruit at the top of your tree have become dry. If fruit has been on the tree for too long and is ripe, it will start to go dry. If the tree is not being consistently watered and is under stress caused by drought or lack of water, it becomes a matter of survival for the tree, so the extremities and fruit at the top of the tree will not get enough water. Temperature fluctuations - hot and cold can cause dry fruit. Mulching around the tree with an organic mulch such as Tui Mulch & Feed will help conserve soil moisture and protect plant roots over the summer months. Tui Organic Seaweed Plant Tonic regularly applied to citrus helps them tolerate temperature fluctuations and improves overall plant health and fruit quality. Immature fruit trees that can't sustain their crop can have dry fruit, 5 years is still quite a young tree, consider removing some of the fruit, thinning fruit will give you bigger fruit and a better quality yield. Too much nitrogen applied to the tree can also cause dry fruit, apply a balanced specialty citrus fertiliser such as Tui Citrus Food or Tui Novatec Premium slow release fertiliser, they contain the right blend of nutrients for fruit trees. The good thing is that these issues should correct themselves next season with regular feeding, mulching and consistent watering. The Tui Team.
The Tui Team
Hi, something is eating the new budding fruit on my lemon tree, lots of flowers but when the buds are about to come out they are eaten? The lime tree beside it is fine. Thanks.
Mark
Hi Mark, it could be slugs and snails eating your flower buds, or earwigs. But it could also not be an insect problem, it could be related to watering - irregular, too much or not enough water. Make sure trees are regularly watered, every 2-3 days depending on the weather. It could also be related to the weather, sudden cold snaps will cause fruit to drop. If a tree is stressed it will drop its fruit as a way of saving itself as all of the plants energies will be going into producing fruit. Citrus naturally drop flowers and fruit (thinning) and will hold on to the fruit they can't cope with the load. If you suspect slugs and snails use Tui Quash, for earwigs the best thing to do is remove their habitat, which is bark and garden mulch. They should move on if there is nowhere to hide. Alternatively screw up newspaper or place corrugated cardboard around the tree, the earwigs will hide in there, dispose of in the rubbish.
The Tui Team
Hi Tui, our citrus crops of limes, oranges and mandarins seem inconsistent. Last year we had excellent fruit, but very little on the trees this year. Any possible cause? Thanks.
Les Dawes
Hi Les, citrus can be cyclical in their flowering and fruiting, there is nothing that causes this, it is just a quirk of mother nature, mandarins are well known for it. It could also be the season, flowering is not seasonal, and can be stimulated at any time by warm sunny weather and plenty of water. Temperatures have been up and down with cold snaps, snow, hail and unseasonably cold days, this inhibits flowering in citrus. Hopefully now with warm sunny weather you are starting to see flowers appear, especially on the lime. Keep the water up to your citrus trees in this warm weather, feed regularly and mulch around the trees to help conserve soil moisture, hopefully you will see new flowers start to appear.
The Tui Team
Hi, what causes holes on my lemons before they are even ripe. Some are a little yellow and then holes?
William Harvey
Hi Bill, it sounds like your citrus may have Guava Moth. Guava Moth is a relatively new insect pest and has now spread throughout New Zealand. The larvae bore their way into the fruit and spoil them. They don't have a 'season' like codling moth and other insect pests as they overwinter in other hosts. Guava moth is hard to control with insecticides as the caterpillar is inside the fruit. There are lures and phermone traps that can be hung in the tree which attracts the male and so interrupts the lifecycle. Collect up all fallen fruit from the ground so that the larvae do not overwinter in the leaf litter in the soil, throw the fruit away either burn or place in the rubbish, do not compost. Some gardeners have placed fallen fruit in the freezer or microwave first to kill off the larvae as if you to try and break the cycle.
Lianne, Tui Team
All Citrus are great fruit
Donald Shanks
Hi, we have quite an old mandarin tree. A few years ago it had no fruit on a big branch on the south side of the tree. This increased each year until now it is only fruiting on one very large branch on the northern side. What do you think the problem is?
Alton Melville
Hi Alton, mandarins are biennial bearers, that is, they flower and fruit every other year. Most citrus, especially mandarins, require heat to initiate flowering, so if something has changed in the surrounding environment, the tree may be responding to that. Also, if the weather is wet during flowering and the bees aren't working, pollination can be sporadic. The tree may benefit from a light prune, citrus flower on new seasons growth and by trimming the tree back you will stimulate new growth and the tree will produce more flowers and ultimately fruit.
Lianne, Tui Team.
Hi, something keeps eating the top leaves of our lemon tree. I spray it with Neem oil and it comes away again, and then they get eaten again.
Jenny
Hi Jenny, it is likely to be slugs and snails at this time of year as caterpillars are usually hibernating, either as a caterpillar or larvae in the soil. If you go out at night time with a torch you may find slugs and snails on your tree, have a look through the foliage you may find smaller snails on the under side of leaves. If you cannot find any sign, it will not hurt to apply slug and snail bait around the base of the tree, we recommend Tui Quash as it is a safer slug and snail bait. If it is caterpillars, it will likely be a leaf roller caterpillar and you will find leaves stuck together in webbing, so they are hard to control with neem oil. If you find leaves stuck together, the best thing to do is squash the leaves together, the caterpillar will be inside.
Lianne, Tui Team
We moved into a house which had 2 lemon bushes sandwiched tightly between a macrocarpa hedge on one side and a covered walkway in the other, with the hedge growing into the lemon trees. When i cut down the macro hedge, it showed all the branches on the lemons below 2 metres high had no leaves at all, though there were some leaves on higher branches. It is completely misshapen and bare on lower branches. If I cut the higher branches, will that stimulate it to grow leaves lower down, to create a more natural and attractive shape? And hopefully then produce fruit!
Jon
Hi Jon, the citrus trees will have been competing with the macrocarpa hedge for nutrients and water and also sunlight. Now the big trees have gone, make sure the lemon trees are consistently watered in the growing season and fertilised as well as mulching around the trees to help conserve soil moisture and to add organic matter back into the soil. You will naturally see new growth starting to emerge, the trees will benefit from a trim to shape to even them up, citrus fruit on current seasons growth so by stimulating new growth there will be more fruit and hopefully it will force new growth from down below. It may take a couple of seasons to get the tree back to shape. The lemon trees may need protection from strong winds as they have been living under the shadow of the hedge, over time the foliage will harden off.
Lianne
Hi, we have a mandarin tree that has healthy leaves and plenty of growth but won't flower. It has been in the same spot for 6yrs but never flowered. It is next to a lemon tree that grows plenty of fruit. Thanks Marty.
Marty Duston
Hi Marty, there could be several reasons for your mandarin not flowering and fruiting. If the tree was grown from seed it can take 7-10 years to get to fruiting stage, if it is grafted or cutting grown it takes 4-5 years until it fruits. If grown from seed non-bearing can be related to its parentage and variation from seed due to cross pollination. Make sure the tree is planted in a sheltered sunny position to help initiate flowering, mandarins require more heat than most other citrus. Excess growth is often a sign that there is too much nitrogen in the soil, or the tree is being fertilised with a fertiliser rich in nitrogen. Citrus require a balanced fertiliser, Tui Citrus Food has an NPK fertiliser ratio of 5-4-7 + magnesium, sulphur, calcium and trace elements. Nitrogen (N) is for leaf growth, phosphorus (P) for root, flower and seed development, potassium (K) for flowering and fruiting. Feed trees in early spring and again in late summer/early autumn. Mandarins fruit on current seasons growth, if the tree is being cut back or pruned each season this will remove the fruiting wood, citrus don't need a lot of pruning, they only need pruning to shape or to remove dead wood. Make sure you have your tree planted in the warmest sunniest spot in the garden, that it is consistently and regularly watered, feed twice a year with a balanced fertiliser, mulch around the tree to help conserve soil moisture and you should start seeing results, as long as your climate is warm enough for growing mandarins. Lemons are way hardier, tougher and less temperamental trees to grow.
Lianne
I have a large quantity of limes and want to make a sweet concentrate - do you have a recipe?
Lauren Susan Murray
Hi Lauren, I make a lime syrup using two methods.
1 cup of fresh lime juice - approx. 8 limes
1 1/2 cups of sugar
1 1/2 cups of water
Combine ingredients in a sauce pan and dissolve sugar. Bring to the boil, remove from heat and place in sterilised jars/bottles, this will keep for up to a month in the fridge. I sometimes add lime zest (1 lime) to the lime juice, sugar, and water. Combine ingredients, dissolve the sugar and then boil. Let cool, strain before pouring into a container, stores for two weeks in the fridge. Adjust the zest to your taste.
Lianne
Hi, it is mid May in Porirua and my lemon tree, planted in the ground Aug 2017 has lots of fruit at good sizes for the first time since 2017, but are still green. The lime tree planted the same time is not as robust as the lemon.
Paula
Hi Paula, the main reason for fruit not ripening is lack of sunlight, especially if there is too much shade or other trees are planted too closely shading each other. Fruit can take a while to ripen, sometimes 6-9 months, depending upon conditions. If the tree has been stressed due to hot dry weather and inconsistent watering or a sudden cold snap then it can take longer for fruit to ripen. Another reason could be pests and disease, if a tree isn't thriving then the fruit won't develop as it should. Make sure your citrus are consistently watered through out the growing season, especially in summer. Feed your trees in early spring and again in late summer, early autumn with a balanced fertiliser such as Tui Citrus food, mulch around the tree in spring and again in autumn to help conserve soil moisture, protect the roots and keep weeds down. The lime tree may be smaller because it is not getting enough sunlight, is planted too closely to other trees, and hasn't had enough water or fertiliser. If all of these things are taken care of, it will just be a matter of time, nature will take its course and your fruit will ripen eventually, you may find that they will ripen all of a sudden.
Lianne
I have a lemon tree and the fruit have a very thick skin and no juice, the flesh looks dry, how do I fix this problem. Thx.
michael
Hi Michael, this is likely to be a nutrient imbalance, too much nitrogen or not enough phosphorus, too much nitrogen affects how much phosphorus the plant can take up. The nitrogen could be from compost, grass clippings, blood and bone fertiliser or sheep pellets. Use a balanced fertiliser that contains all the elements required for healthy plant growth that contains nitrogen, phosphorus and potassium (NPK). To fix this imbalance apply a phosphorus rich fertiliser such as Super Phosphate, at the moment plants aren't actively growing or taking up nutrients so do this in early spring.
Lianne
I have a new mandarin planted in coastal Hawkes Bay. The leaves are curling, dropping, showing yellow patches and some have a brown discoloration on the underside. It is budding well though. Any suggested treatment?
Brent Wood
Hi Brent, you don't say how recently the tree was planted, it could just be transplant shock and the tree will come right. At this time of year moving from one season to the next it is normal for citrus leaves to yellow and drop, and not a big concern if the new growth looks healthy. The underside of the leaf may have overwintering white fly eggs, you can probably scrape it off with your fingernail. Spray with a suitable horticultural spraying oil or plant based oil, making sure the underside of the leaf is well covered with spray, your local garden centre will be able to recommend a suitable spray. The leaves curling are likely to be caused by cooler temperatures, citrus are sub tropical fruit trees so like the warmth, or, it can be caused by insect damage, usually sucking insects. Regular sprays with a horticultural spraying oil will help with this, as well as temperatures warming up now spring is here. If you are coastal and have prevailing winds, make sure your tree is in a sheltered spot as salt laden sea spray can cause the foliage to burn. Feed your tree in early spring, so now, with a citrus fertiliser such as Tui Citrus Food or Tui Enrich Fruit, Citrus, Tree and Shrub fertiliser. Feed again in late summer, early autumn. Make sure your tree is consistently watered through the summer months and mulch around to help conserve soil moisture, Tui Mulch & Feed is a great mulch for fruit trees. Regular applications of Tui Seaweed Plant Tonic will also help stimulate root growth and improve overall plant health.
Lianne
Hi, I planted a lemon tree a couple years ago and it has grown 2 metres but only has about 10 branches and is gappy. If I prune it will more branches start growing?
Andrea
Hi Andrea, citrus can be pruned to shape, cut it back by one third, as long as the risk of frost has passed, now is a good time to do this, if there are any late frosts after pruning the new growth will get damaged. Any wounds larger than your little finger should be painted with a specialty pruning paint or water based paint, this keeps the lemon tree borer away which starts flying in early spring laying its eggs which when hatched bore into the trunk and weaken growth. Citrus trees fruit on new seasons growth so by trimming or pruning you will encourage new growth which will eventually give you flowers and fruit. After giving the tree a prune you may only need to do light prunes to encourage new growth.
Lianne
We transplanted a Meyer lemon tree into a pot on our deck 2 years ago. It did not like the move and quickly started dying. We have rescued it to now being abundant with flowers and new fruit. Would this mean it’s gone back to new first year fruit? That is, do we need to remove the fruit for a better harvest next year?
Kyle
Hi Kyle, Meyer lemon trees fruit year round in warmer regions, and citrus flower and fruit at the same time, fruiting on new seasons growth. If the tree is healthy and has a lot of new growth then it will likely hold on to the fruit, the fruit will naturally abort if the tree cannot sustain it. The key to success when growing citrus in pots is regular and consistent watering, finding the right spot, and fertilising the tree. Use a controlled release fertiliser such as Tui Enrich Fruit, Citrus, Tree & Shrub, or Tui Novatec Slow release fertiliser. Feed in Spring and again in late summer, early winter. Make sure the tree is in a pot that is big enough for the tree to grow, a pot 50cm in diameter and depth would be the minimum size you would want to go. The tree can be pruned to shape, remove weak spindly growth and if you have vigorous shoots, they can be cut back by one third.
Lianne
I was given a finger lime for Father’s Day so I repotted it in bigger pot and it really started growing well with heaps of new growth. Now some of the new leaves are getting some yellow areas on the new leaves. No insects to be found. Have given some Epsom salt’s, I have no idea what’s causing it, have taken it out of direct sunlight in case it’s sunburn. Would you please give me your advice. The tree is quite healthy. Would seasol help. Many thanks.
William McColl
Hi William, yellowing leaves can be caused by several things, one could be transplant shock, you don’t say how recently the plant was repotted, Seaweed Plant Tonic is beneficial to plants as it reduces transplant shock as well as stimulates root growth. Apply weekly at a rate of 70ml per 9L watering can, once the plant shows signs of recovery reduce to every 2-4 weeks. It may be that the plant just needs time to recover.
Another reason is poor drainage, use a quality potting mix for your finger lime such as Tui Citrus & Fruit mix or Tui Pot Power, both contain a controlled release fertiliser for sustained feeding. Ensure the potting mix you have used contains a controlled release fertiliser.
Finger limes are sensitive to sudden cold snaps and frost, when a plant is stressed the first thing they will do is drop fruit or leaves to save themselves, the plant should recover as temperatures warm, Seaweed Plant Tonic helps plants tolerate temperature fluctuations.
Nutrient deficiency is also a cause of yellowing leaves, it could be lack of nitrogen, magnesium or trace elements such as iron, if a quality potting mix was used there should be enough nutrients to sustain the plant for at least six months.
Finger limes prefer full sun, plants take time to recover after repotting so placing the plant in part shade will be beneficial for a couple of weeks, keep an eye on it and move it back out into full sun when you feel it has recovered. Make sure the plant is consistently watered, pots dry out quickly and so the plant may need watering daily until it becomes established. Ensure the pot size is big enough to retain enough moisture in the potting mix. Keep an eye out for scale insect as they can be a problem and usually attach themselves to the main stem of the plant, the presence of ants is a sure sign that you have an insect problem, talk to your local garden centre for a suitable control for sucking insects. Also consider liquid feeding throughout the summer months, Tui has a range of liquid superfoods – Citrus and Fruit is prefect for your finger lime, it also contains seaweed plant tonic and the correct balance of nutrients for growing citrus and fruit trees, check the link here https://tuigarden.co.nz/inspiration-hub/ideas-and-inspiration/discover-tui-liquid-superfoods/
Lianne