Can you please tell me why my Mandarin tree that is growing in a pot has all of a sudden lost all of its leaves? It has got fruit on it and has been fed with citrus food.

• Plants lose their leaves (defoliate) due to stress.
• This could be due to insufficient watering, plants in pots require watering every 2-3 days, at least 5 litres per watering. In summer the plant may need daily watering.
• Overwatering can cause leaves to drop, this could also be compounded by poorly drained potting mix.
• The plant may need repotting, has it become root bound. Depending upon the size of the pot and how long the plant has been in the pot, it could need repotting into fresh potting mix.
• Over application of fertiliser or the wrong fertiliser for plants growing in pots.
• The best fertiliser for plants growing in pots and containers is a controlled release fertiliser such as Tui Enrich Fruit, Citrus, Tree & Shrub .
• Tui Citrus food is not suitable for use in pots and containers as it does not have any control mechanism and can easily be over applied, the build up of salts accumulate around the pot wall and burn the roots. 
• If you suspect you have used the wrong fertiliser or over-applied fertiliser put the hose on the plant to flush out the excess fertiliser for at least 10 minutes. If possible scrape up any excess you can see in the pot.
• Regular applications of Tui Seaweed Plant Tonic will help the plant recover, apply weekly at a rate of 70ml per 9L watering can. Once the plant shows signs of recovery reduce applications to every 2 weeks.
• To help the plant recover remove or thin the fruit, the plants energies are going into producing fruit rather than recovering and producing new growth. 

Read the Tui Citrus Grow Guide

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