New! Growing Cactus From Seed!

I start the process with a clean plastic tub such as this one

Then add my choice of potting soil, the best stuff I've found for straight out of the bag use

approximately 2-2.5" deep in the tub

then i mix in warm tap water, 4-5 cups worth to totally saturate the soil

I rough level it & then spray it down really good with distilled water

Then if I'm planting multiple varieties of seeds per tub, I'll cut some plastic strip dividers from an old milk or vinegar bottle

I start the process with a clean plastic tub such as this one. Then I add the dividers, toss in the seeds, label and date the tags, and then spray things down real good again with distilled water

Then I put the lid on and seal it, creating a nice humidity chamber and put the tub on a heating mat under the lights. I use two each, cheap 2 bulb 4' shop lights with cheap T12 cool white bulbs, although have considered switching out to T5 lighting. Tiny seedlings turn reddish with too much lighting.

I run the lights from around 5:30 am to 9:30 pm and the thermostat controlled heating pad stays on all the time, maintaining a soil temp of around 85F.

I'll open the tubs every few days and spray mist with distilled water.

When the seedlings get around this size, I open the lids and let the seedlings start to acclimate to the outdoor air

when they get around this size, I take them out from under the lights and put them on a table in my gh, which is nothing more than an open air, unheated lean-to type with tinted plastic Suntuff UV coated panels.

Another important point is not all seeds (or seed sellers) are the same. I've learned it's critically important to separate the live seeds from the dead (un fully developed embryo's) seeds, as this greatly affects germination rates. I use water separation for all my tricho hybrids, pouring off the 'floaters' as they tend not to germinate, or if they do at not nearly the same rate as the 'sinkers'.

I'll repeat the water separation process several times, eliminating all the floaters. This pic somewhat illustrates that, a batch of 'floaters' is planted on the left side of the tub. Look at the date all three batches were sown.

1 month old saguaro seedlings hardening off (below) and not all seedlings of the same batch grow at the same rate

I'm fortunate in location in that i can grow seedlings and plants year round, outdoors, using natural lighting, and only using artificial lighting for some seed germination.

I dont think there's any way to prevent some etiolation from occurring with columnar's under artificial lights; the sooner a person can get them in natural outdoor lighting the better.