[steampig]

Against my better judgement, my other half insisted on growing two sweet pepper plants in the greenhouse. They have developed dark brown spots all over the underside of the leaves. Does anybody know what this is, and do i need to quarrantine it on the compost heat.

[paintedlady]

Not quite sure what to make of it.  Is it possible to post a picture?  I've grown sweet peppers indoor (and outdoors) and the biggest problems I've had, tended to be spider mite and whitefly because they are sensitive to temperature, sunlight & humidity changes.

The fact that it is underside a leaf may suggest a pest rather than disease or environmental stress (but given the awful weather could be a combination of anything and I am only hazarding a guess here of what it could be!)  I don't know what to suggest but as a precaution until someone more knowledgeable can help, I would isolate them from your other plants (including cucumbers, tomatoes, aubergines etc) as the more common pests can infest them all.

[steampig]

Not quite sure how to post a pictue, but the problems seems to have occurred over the last two days. The problem does appear to under the leaf but looking down on top of the plant a darkening can be seen on the upper surface. I suppose it could be cold related because it has been rather v=chilly up here recently