Once you've planted your new lime tree and set it on it's merry way, you certainly don't want pests or diseases to interfere with all the good growing the tree is doing -- so here's what to watch out for:
• Aphids and scale can plague lime trees. Both insects produce honeydew, causing sooty mould. Treat scale with horticultural oil, remove the sooty mould with a soapy cloth. Stop ants climbing the tree and “farming” the insects for their honeydew by banding the trunk with horticultural glue on a cardboard collar.
• Citrus leaf miner burrows into leaves and distorts them. Spray with horticultural oil, ensuring the whole leaf area is wetted. Leaf miner traps are also available.
• Citrus gall wasps produce swellings on branches. Depending on the time of year, control by pruning affected branches below the gall and soaking the galls in water until they rot. Or smear the galls with horticultural glue and finally spray the whole tree with kaolin clay to stop the female wasps from laying eggs. You can also hang gall wasp baits.
• Bugs such as spined citrus bug and bronze orange (also called stink bug) can build numbers in spring. Pick them off and drop into a bucket of soapy water or spray with pyrethrum. Wear gloves and glasses when handling as their excretions are irritating.
• Citrus scab is a fungal disease that causes dry lesions on fruit during times of wet, humid weather. If you’ve experienced the problem before, then spray in advance of wet spells with copper hydroxide.
• Melanose is a fungal disease causing speckled brown patches on fruit, leaves and branches. Spray in early spring with copper hydroxide. Products mentioned are available from good hardware stores, garden centres and online.
In our latest issue (on sale November 5, 2020), Justin Russell explores the tangy world of limes and how to grow them, from Tahitian to native finger limes. If you pick up an issue you can also learn about growing capsicum and fennel and strawberries as well as how to get the best eggs from your chooks. Get your copy now!
For more tips on growing fruits such as lemons and lime try the following:
By: Justin Russell
First published: October 2020