Cleaning Greenhouses/polytunnels

It's still a bit early for this but last year I used sulphur candles in the greenhouse to try to eradicate any pests and diseases, the main one being tomato leaf mould. This has reappeared this year but a lot later in the year so not really a problem except it will likely strike again next year if I don't take any action - and makes saving my own seeds problematic as it can harbour in the seeds .

I wondered what, if anything others do?


Sulphur candles cn be quite expensive dan you just use flowers of sulphur do you think?