You could probably try a sulphur candle to fumigate it. The fumes get into all the spaces that you can't. You do have to remove all the plants, and yourself, whilst it is burning.

My mate uses a steam cleaner.

A drop of bleach in soapy water does a good job. The sulphur candle sounds a good idea as well. The steam cleaner would also work to get rid of insects if directed over them but be careful of cracking the glass. Personally I find bleach works well.

Thank you all - shall try the bleach as I don't have access to a steam cleaner. Might try the sulphur candle later on when the last tomato plant and the sweet peppers have finished - they have started flowering again.

Try a mix of 50% rubbing alcohol and 50% water placed in a spray bottle, it is very effective in killing spider mites. The problem with bleach mixes is that It is a VERY strong oxidizer and will corrode almost any metal even in small amounts. It's use could cause damage should your greenhouse glass be framed in metal. Stay away from the fumigation method. A former botanist friend of mine tried it as he had done many times before only in this final instance it was concluded he did not make it out of the greenhouse in a timely manner. Most likely it was a momentary distraction.

Oh poor man, that sounds scary especially with my asthma. Right then lets try the rubbing alcohol. Are you sure vodka wouldn't work as well - we seem to have loads and no-one drinks it!

Ooch, that's nasty, Eclectic. Poor guy.

UK bleach is not as strong as the US stuff...an American friend was horrified we put bleach down the loo, thought we might die of poisoning if we peed on it...it will not corrode any metal.

Cammomille:

You have vodka???.... Can anybody send me a bottle or two of vodka? I have slot of spider mites to kill this winter!

Silly - it would never last the journey!

you can actualy buy a proper fumigater that will kill everything in your green house and i think as its so big its so worth it i think . i used to work raising chickens for buxted and the sheds held 30,000 chickens and when it was empty you only needed 3 of these fumigaters in this huge building thats old and wooden .its at least worth looking at .

Thank you all - had a Suttons Seed catalogue this morning and they have fumigator thingies in them so might have a go in the Spring. I shall light it and run - just in case.

i tried getting in a chicken shed a few feet for a broom andwish i didnt lol . the ones we used were electric but same theory x .