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Pests Spotlight: Leaf Miners

Signs Of Damage By Leaf Miners

You may have Leaf Miner damage if you see the following signs:

  • Wiggly lines on leaves usually yellow or white in colour

  • Spots or blotches on leaves

What's Causing Them?

The wiggly lines are caused by larvae literally eating their way through the leaf. Adults are often black to gray flies with yellow stripes and clear wings. The flies themselves don't cause any damage, and lay their eggs on the underside of leaves.

Plants that Leaf Miners Love

Leaf Miners attack all sorts of plants including:

  • Leafy vegetables e.g bak choy, kang kong

  • Fruiting vegetables e.g ladies finger, tomato, eggplant

Treatment Options

​Use Organic Neem Oil Concentrate to combat plant pests and fungus. It is a non-toxic solution that causes insect pests to reduce or cease feeding, prevent larvae from maturing, and reduces or interrupts mating behaviour. Neem oil is a natural product of the Neem Tree, and is effective at killing fungal spores too. ​ Unlike chemical pesticides that have instantaneous results, organic pesticides like Neem work best when used as a preventive tool and as part of an overall Pest Management Strategy. In treating pest infestations organically, it is important to break the life cycle of pests by preventing any larvae from maturing and also preventing mature pests from feeding. ​ It is important to use Neem Oil solutions only in the morning or evening, when it is cool, to avoid leaf burn. ​ For Early Stage Infections How You’d Know: Only a few leaves are affected and the majority of the plant is still healthy and lush. ​ What You Can Do:

  • Pick off any leaves that have signs of tunnelling.

  • Crush leaves at the tunnel to squash any larvae before composting.

  • Spray leaves liberally on both sides with neem oil solution once every 7 days. This has antifeedant properties and prevent larvae from becoming adults and laying more eggs.

​ ​ For Severe Infestations How You’d Know: Majority of leaves have severe tunneling. What You Can Do:

  • Give the plant a hard prune and trim away all affected leaves.

  • Crush leaves at the tunnel to squash any larvae before composting.

  • Dilute neem oil solution as directed; spray liberally on both sides of the leaves once every 3 days for 2 weeks.

  • Reduce to once every 7 days for 2 weeks.

  • Continue as a preventive spray once every 2 weeks thereafter.


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