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Leek Moth


Leek Moth

Usually appear in

Spring to Autumn.

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Caused By:-     The larvae of Acrolepiopsis assectella


The leek moth, Acrolepiopsis assectella (Lepidoptera: Acrolepiidae) is a local pest in Britain, being mainly found along the east and south coast of England, but as the temperatures are getting hotter it is moving inland. the larvae of this species feed on cultivated species of Allium such as leek, onion and chive and can grow to 12mm. In parts of continental Europe or Canada where it is more abundant, it is a serious pest. The larvae mine the green leaves, and occasionally in the bulbs, of their host plants. This reduce the marketability of the crops they attack. The moth produces two generations during the summer. The larvae are active during May and June and again between August and October. When the larvae have finished feeding they emerge from the plant and spin net like silk cocoons, usually on the foliage of the foodplant or close by. It then over-winters as an adult moth up to 18mm long in sheltered places.


Examine the foliage of Alliums, and if you spot damage you can usually track down the larvae and destroy them. Pay special attention to your plants from May onwards. There is currently no pesticide effective against the moth that is available to amateur gardeners. An alternative, and very effective, way to protect your crop is to grow alliums under fleece or, even better Enviromesh. If all else fails and your crop of leeks has been badly infected you can always cut off the foliage and it will re-grow, albeit a little smaller. Cutting the foliage will not work with other allium species.

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