I am new to vegetable gardening and this is the first year I have attempted various vegetables other than tomatoes and courgettes.

I am growing some Little Gem lettuces in troughs in the greenhouse and I have just noticed some tiny holes in the middle of some of the leaves. There are no sign of any pests on the leaves. Does anyone know what causes this? Should I spray with insecticide? Is it a good idea to spray edibile plants and vegetables?

On a different subject should I remove the seed leaves from vegetables once they are established? I have always done so on my tomatoes and courgettes, as they trail in the soil, but should I also do so on cucumbers, basil, lettuce, peppers etc.?

Axel