black death

[PAULW]

Oh to be able to grow some decent onions without getting stricken with sooty mildew every year, we had a mild touch a week ago so I sprayed with Dithane but it rained heavy yesterday and the onions took another hit, apart from fixing up a permanent umbrella spray of Dithane over the onions or growing in a polytunnel the only way we get any onions is to grow lots of overwintering ones .

[Two_Sheds]

That looks like you've got leek moth maggot damage, and a secondary infection has set in (due to the humid weather?)

Sooty Mould, Black Mildew
This is a small black fungus which grows on the honeydew produced by aphids and other insects. It does not actually grow on the plant, but on the surface of leaves, which blocks out the light and prevents photosynthesis.

Sooty Mould can be removed by wiping the leaf gently with a cloth or tissue dipped in warm water. http://theseedsite.co.uk/pests.html

[PAULW]

TWO SHEDS
Last year we had perfect healthy stand up straight happy onions one day, it rained for ten minutes that night next morning it looked like someone had tipped soot over the onions leaves with patches as in the picture leading to the leaves collapsing and turning mushy,the mould was washed off with Dithane from a spray but to no avail, the leek moth turns up a couple of months later and hammers into the leeks but we do not have an insect problem with the onions.