[Salmo]

Planted leeks out about a week ago. Today found nibbled leaves. Investigated further and unfolded 3 tiny grubs at the base of the leaves. Last year was the first year we had leek moth. This does not bode well for this years crop.

I know the advice is to net them with mesh. Are there any chemicals that can be applied?

[angelavdavis]

Hi Salmo,  I visited Wisley yesterday and they were using leek moth pheromone traps like these http://www.gardening-naturally.com/acatalog/Leek_Moth_Trap.html.  I haven't used them myself though.

[DD.]

The main idea of pheromone traps is to give an idea of when the pest is around so that action can be taken. They will not trap all of the pest.

Note the difference in the text between the pea moth trap

http://www.gardening-naturally.com/acatalog/Pea_Moth_Trap.html

and the previously mentioned leek moth trap.

The difference being is that there is no chemical action you can take against leek moth.