Tomatoes- Help please! - What's this?

[clipper]

Please, can anyone identify this brown powdery mildew/fungus etc on my tomato plants?

They are in a greenhouse in grow bags and the brown powdery substance is on both sides of the leaves.

Any remedies would be very welcome.


Thanks

Clipper

[Geordie]

Its always a little difficult to tell but going from the colour, ie its brown spores and not white I'd guess at Botrytis Mould. Sometimes called grey mould which is a little confusing as the spores are brown. Starts at the tip of the leaf and sprerads in a vee shape, covering leaf with the 'mould'. Am sure google will offer you some pictures to compare.

[Alison]

I think that avoidance is easier than cure with this, as I remember it's often due to over crowding or inadequate ventilation or that's what I was told when I'd over stuffed my greenhouse one year!

[clipper]

Geordie/Alison,

Thanks for the replies.

I'll explore Botrytis mould with Google and see what I can find.

We've always given plenty of ventilation, but we grow 3 plants in each grow bag. Too crowded do you think?


Thanks
clipper

[SarzWix]

It often seems to start when drops of condensation from the roof drop onto the leaves, and don't dry off quickly enough. So ventilation helps, by preventing the condensation in the first place, and by giving air-flow enough to dry off any drops which do happen.


Interesting article here by Medwyn Williams (Chelsea Gold Medal Vegetable grower) about 'Overcoming Botrytis' http://www.nvsuk.org.uk/medwyn-willi...-show-285.html