My lemon tree is infested with Scale Insect. Can you tell me what conditions scale find favourable and what time of the year they are likely to hatch.

• Scale insect can be a year-round problem; populations increase in the summer months and are active from spring through to late autumn.
• When plants are not actively growing, weakened or stressed during dry spells or due to insufficient watering, scale insect become especially active. 
• There is a crawling stage that looks like specks of dust, these are spread by wind, birds or other insects and carried to new plants. If conditions are ideal they feed and multiply forming into adults with their protective shield. 
• Scale insect are sap sucking insects and are hard to control because of their protective shield. Spray with a plant spraying oil or pyrethrum based spray available from garden centres and hardware stores.
• Insects can be removed or scraped off using fingers, this is okay for few, but not a practical way to stop them returning.
• Repeat sprays may be required, make sure the underside of the leaf and around the flower buds are treated as well.
• If the tree is flowering don't spray while bees are foraging, it is best to spray early in the morning or late afternoon.
• Cultural practises to help control scale insect include picking up any fallen leaves or plant material from around the plant that may have scale on them and dispose of in the rubbish, scale can overwinter in the leaf litter and soil.
• Apply Tui Seaweed Plant Tonic to help stimulate root growth and make the plant more robust, it will also help the plant recover.
• Make sure the plant is well fed, use a specialty citrus fertiliser such as Tui Citrus Food. Apply every 6-8 weeks in the growing season, spring through to autumn.
• Water trees regularly, for established trees water weekly. 
• Use Tui Mulch & Feed to mulch around trees in spring and again in late summer early autumn. This conserves soil moisture, feeds the soil and suppresses weed growth. 

Read the Tui Citrus Growing Guide

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