Hmm! I wouldn't have thought those mesh-bottom trays could support any weight at all without sagging. But with some kind of supports under them ... that might just the thing. Thanks!
Up to now I haven't used cap mats to water seed starting trays for multiple days unattended. Just the opposite, I lay the mat and seed trays right flat against the bottom of the water-holding tray. It's there to help me avoid over-watering. Next year, with a better-wicking seed mix, maybe I can reduce my top-watering to just once every week or so.
>> i mean, i agree that some large seeds will germinate well in moist bark. just not small seeds.
I just assumed that my petunia seeds all died because they fell into gaping cracks in the surface. Maybe the deeper parts of the cell would have been too coarse even if I had put a layer of vermiculite on top for tiny seeds to sit on. I would experiment, but I'm already leaning toward somewhat less coarse bark/commercial mixes for seed starting (to get more wicking up from my mats).
I think I'll always aim for a coarser seed mix than most people choose, because aeration seems so important to me, and I don't mind top-watering or misting twice per day if necessary. If very small seeds just can't handle that, I'll have to adapt. i THINK I started Lobellia that way one year, with a very coarse bark mix, and thought I had fine germination. Of course, with dust-like seeds, maybe I sowed three times as many as I thought I did, and the germination was terrible!
BTW, an idea you suggested like stuffing a small wick into the bottom slit of each tray sounds better to me when I picture short lengths of bulky yarn. If it's necessary for good contact, that would be fairly easy.
>> i did not realize you have a large 'production' going on.
In Springs when I DO get busy with seed starting, I usually have four trays going, either starting seeds or potting up seedlings. If I get any kind of cold frame structure built, I hope to increase that.
