I've had varying results with spraying different things on soil recently. Mold came up on some gritty mix (which I salvaged and sterilized from some cuttings tapla sent me) I was (am) using to root some (I think philodendron or the like). I'd treated the cuttings with cinnamon, so I tried that. No dice, though it may have suppressed it slightly. I also tried diluted (chamomile) tea solution, vinegar, insecticidal soap, and hydrogen peroxide solution. Combined with increased ventilation, some combination of those wiped out most of the mold--the soap (castile peppermint soap) probably did the most, although once it dissipated, the mold came back if I didn't ventilate enough. Vinegar seemed to work OK too, although unless you flushed it out, an already-flourishing plant might suffer if your pH gets too low. I did the same type of thing for some peat/perlite/bark mix I'm starting some seeds in. For some old seeds that all just rotted (whoops), the mold came back eventually, depending on moisture level. Only very small amounts survived in other containers, and don't do much unless I add too much moisture. I guess the moral of the story is: it's probably not worth the effort :) Note that some of the stuff I was working with, was already sterile. Fungus spores of one kind or another are ubiquitous, so if you wipe out one population, that just makes room for another to move in. BTW, I haven't had trouble with spraying undiluted H2O2 (hydrogen peroxide--what you buy in the US is usually 3% solution) on or around plants, so that may work. Trouble is it breaks down rapidly and then the mold can come back (I've found it to be less than satisfactory for mold control, by itself). PS, Al: it's sodium hy*po*chlorite ;) Just in case anyone was wondering...

Agree. Damp-off is caused by the grower, not by the soil-less mix. It is caused by excessive moisture and inadequate air circulation around the seedlings. And the beneficial microbes in compost, if added to your seed starting mix, will actually kill the fungi in the mix that can lead to damp-off when proper conditions are not maintained by the grower. Many of us who grow from seed routinely add compost to our mix - both starting and growing-on mix - with no problems (and with bigger and healthier seedlings as pictures in several posts can attest ;). Indeed most soil-less seed starting mixes on the market already contain some compost. Sorry, but flushing seed starting mix with water - boiling or otherwise - may make the grower feel better but it merely drains out whatever nutrients it might have contained in the mix. But do your own test comparison trying some each way - always room to learn something new. ;) Dave PS: It's fine to use your perlite as is. It is an inert material.

Compaction is probably not the main worry about the vermiculite, especially in a light mix like Mel's Mix made "by the book." It will eventually "break down" into smaller particles, which is why Mel says to start with the coarsest grade you can find. Over all it will last a long time and make a major contribution to your soil quality. Not only will perlite not do the same task, but perlite will add its nasty texture to your soil, making it unpleasant to handle (which is a very un-SFG thing, as one of the fundamentals of SFG is that you work on your SFG and handle your soil some every day). Perlite will also float to the top of your bed, at which point it will either wash away or sit there not providing any benefit at all to the consistency of your soil. I have no idea about the bark, I would wonder if it is even more acidic than the peat, which wouldn't be a good thing. I don't have any especial love for peat either (although it is worth noting that it is being generated in Canada faster than it is being harvested, and is indeed a renewable resource) but it does seem to result in a soil mix, built by Mel's formula, that was excellent from the very start for growing vegetables and flowers. If I were to make any changes in future boxes I might cut down on or leave out the peat, but my soil formula would alway contain at least 1/3 vermiculite if possible, due to my experience in the pre-raised bed days of the first SFG book, where vermiculite was by far the best addition I made to my native soil, producing better results, that showed quickly and lasted longer, than any of the other stuff we added over the course of many years. In my raised SFG I plan to add a little vermiculite and a lot of fresh compost every year.

Your problem is what you have in the containers already. Adding more junk to it will only make it worse. Read here about BER and what causes it - and it isn't lack of calcium in the soil. Then do some reading on what growing mixes belong in containers. They don't include garden soil or pea stone or compost or bone meal. Container size is yet another problem. Sorry but based on the information you have provided and this late in the season it is going to be really difficult to get any usable tomatoes out of your set-up no matter what you do now. Better luck next year. Dave Here is a link that might be useful: BER FAQ and discussions