This is not a good idea. PM spores are quite common in nature - so even if you burn the house - it won't help. Usually it means that you have big difference between night and day temperature - so you have dew on the leaves at the night time when temperature is at the lowest, no air movement and high humidity.

Look for Immunox Spectracide fungicide. I think it is sold in Home Depot - spray several times week apart. There is a big gun thing - fungicide Topaz. You can get it on ebay. Works like a charm for 6 months.

yep your are right on target. days have been in the 90s and night 50s I do have fans on day and night. I will try one of these and glad I don't have to toss all my plants in the trash. Thank you for your help, John

IMO PM is mostly a reaction to a stressed plant. You say 90s, do you have air conditioning? Are you letting them get too dry (that's my major problem that induces PM in pretty much any plant...even outdoor hardy plants)?

I suppose it's like us, their immune system gets compromised by conditions.

No air conditioning we are all sweating it out together.

Well, I hope you don't get measles or PM with your lowered immunity :) No AC...how awful.

Increasing the air movement across the plants may help. Also, if you wish to try avoiding the heavy chemicals, you might try spraying the plants with a strong chamomile tea.

I wonder if having your plants slack/double potted might help? While this method is primarily used for maintaining even moisture with touchy plants, it might, in your situation, provide a degree of evaporative cooling to mitigate the heat. Slack potting

I agree with Irina. But also, PM is STUPID EASY to get rid of that it's laughable. Do increase your air movement if you can but more importantly, simply spray your plants with a soap based spray (insecticide soap works fine) or a fungicide as mentioned, or even simply wash them off with a little Dawn dish liquid (not the anti-bacterial stuff) and rinse the leaves. Presto, you kill the pathogens easily. Neem oil also works if you use oil based products, or sulfur spray also works great. Just never use both sulfur and any oil based products together as they cause phytotoxicity. Chamomile tea is also a good suggestion as it is a natural anti-fungal. Great to keep seedlings from dampening off, too.

I wouldn't say it is that easy ... Hyn - you probably have the magic - pests die when you give them The Look. PM can be pretty persistent on PM magnets- Smithiantha is one of them. Prevention is always better. I keep the fan running and so far so good.