I've seen a method where Lithops were grown in sterile closed pots for long periods and growth was greatly accelerated. That being said, I prefer the open air and sun. I start all seeds in a closed, humid environment until germination starts and then move pots into filtered sun.

Never used just verm&perl, can't help with that. My belief is that it's better to learn how to avoid algae, bugs and disease by improving conditions and practices, not by relying on a sterile environment. The sun and the wind will do their work; you find your place in between.

My approach is similar to hanzrobo. Keep the pots in high humidity until germination occurs and then gradually increase fresh air. Best to avoid algae, mold and problems with damping off.

Thank you.

My succulents will always be indoors - the only sun they will get is through east/west facing windows and the only fresh air through open windows. So it has to be a managed environment. Not a problem for mature plants, but a hassle for seedlings.

I may try to set up an experiment - keep some pots sealed, some open and some in-between. See what happens.

I've just got my first Lithops (?) seedling (germinated after 10 days), though the other 26 seeds haven't done anything yet. Fuzzy picture at the link below.

Chris

Here is a link that might be useful: Lithops (?) seedling

Chris, I'd be tempted to reverse the perlite and vermiculite. Vermiculite tends to collapse...even turn to mush. If placed on top of your germination container it would be useful for seeds settling. As the roots emerge and grow downward, they will really benefit from the coarse texture of the perlite.

Similarly, I put a layer of my usual coarse textured Fafard medium in my seedling flats, then add a dusting of germination mix on top. Even tiny seeds can settle in happily for the few days required. Soil to seed contact is important.

One can also use clear plastic cups (like one gets iced coffee, or iced tea in, in the NY tri-state area). Plant the materials in the bottom cup & invert a 2nd cup over the top, for a dome-like or greenhouse effect.

This still allows for (1) opening & closing at will, allowing for air circulation, (2) being transparent enough to shoot pix thru & (3) closing well enough to conserve humidity (it just needs to close, it doesn't need to seal shut), as I suggested before, sealing it shut is an invitation to ROT.

{{gwi:514870}}

Those ridges at the edge of the cup are the bottom ridge edges of the top cup, sitting just on top of the bottom cup (whose top one can't see at all).

Works beautifully.

@rhizo_1

Ah, you've hit the nail on the head. My original reason for using perlite as a top layer was because it would dry out and prevent rot. But it's too coarse - which has become clear both in my handling and in my photos.

I shall try reversing the strategy as you suggest. I shall also try grinding the perlite down into smaller particles (though I can see perlite dust getting all over the place, including my lungs!).

@pirate_girl

Thanks for the further suggestion.

Chris

FYI: lots of folks here talk abt rinsing perlite to keep the dust down (I don't bother); if you're going to grind it, you may wish to wear a face mask (which I do when mixing up the mixes w/ my perlite). Easy to get mask to cover nose & mouth from the dentist or doctor's office.

I don't know what seeds you're growing, but maybe I'm missing something or misunderstood something?

The whole point of covering or enclosing the seeds is so they DON'T dry out. If you allow the Perlite to dry out, your seeds will dry out too & not germinate. Seems counterproductive at best.

Have you ever grown anything from seed before?

@perlite_girl

I suspect that you've misunderstood about the perlite. This was soaked. The intention was that there would be sufficient moisture for germination, but enough dryness eventually to prevent rot once the seeds had germinated. This hasn't worked in pots that sprung a leak (!) during germination (so the perlite dried out quickly), or where I deliberately cut down on the moisture..

Otherwise, the germination rates are maybe respectable for a first try.

Chris

I have had great success with pretty much all mesembs by keeping the seedling tray sitting in water so that the mix remains moist, while exposed to the constant air of a nearby fan set at a high speed. Spring and fall sun are OK, summer seedlings need shade.

Some species won't survive unless constantly moist - like Muiria and other "difficult" species.

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