Mr.Peabody said:Ah, keeping them next to the big one, so they have an example of how to be, eh?![]()
They're very cute. It's hard to imagine they can grow into large, gorgeous monsters with 3 inch spikes!

lobo said:Is that soil under the baby?
I have 8 babys like that in a humidity chamber...
wearepeople said:Archmange,
Awesome! Growing cacti from seed is a test of patience.
I think Lobo was asking because keeping seedlings in a humidity dome is typical for the first few months. Also, its common to germinate cacti seeds in sand of some sort. 20% worm castings with 80% pool filter sand is a good mix.
Desert soils tend to be more alkaline than acidic. The expandable discs are made of peat which is very acidic. Peat is often used by horticulturalists to "acidify" soil mixes because its so acidic.
Trichs like soil pH around 7.3, if I remember correctly. Sometimes folks use dolomitic lime or other alkaline gardening materials to adjust the pH up towards basic.
But hey, if the seedling discs are working for well for you, keep on keeping on. :thumb_up:
wap
Entheogenerator said:I would recommend the same things as wearepeople did: alkaline soil, and a humidity tent if necessary. The corner of a Ziploc bag can be used, if you set it up like a little teepee over the seedling.
Also, perlite. Lots and lots of perlite. At least half of your soil mix should be perlite, or another additive that will allow for fast drainage. I think some people use use rocks (lava rock would probably work well), but I have not tried it so I cannot speak from experience. Some choose to use sand for this, but I have had several people tell me that sand tends to compact quite a bit after a while, so I prefer to avoid using too much of it.
Some people tend to make really complex mixes with small amounts of coconut coir (works the same way as peat moss, but won't make the soil acidic), lime or something else to make the soil alkaline, sand, worm castings, etc. This has it's advantages, but a mix of 50% commercial cactus mix and 50% perlite will work provide an adequate substrate for your cacti.
I would also avoid having too much organic matter in your soil mix (wood chips and things like that). I would recommend getting a 1/4" screen and screening your cactus mix to take out big pieces of wood.
Sacredcactus.com and Magicactus.com both have some really good advice for beginners regarding soil mixes for lophophora and trichocereus species. The two genuses have basically the same soil requirements.
How low does it take to dry after you water it?Archmage said:Wow. Soooo much information here to absorb.
My substrate was based on http://www.homedepot.com/p/Supersoil-1-cu-ft-Cactus-and-Palm-Mix-72051490/204698445 mixed about 60/40 with rock and dirt from the Mojave desert.
It definitely had all those sticks and woodchips, etc built into them. I can certainly do the ziplock humidity chamber Entheo, if you think it's necessary... No problem at all. I was, in fact, surprised that they germinated but once they did, I figured - eff it - I suppose i'm raising cacti now. I have 10 more I'm waiting on to pop.
They make special pH meters for soil. I'm not sure if there's a way to get pH strips to work with soil, but the meters made for soil are pretty inexpensive anyways.Archmage said:How does one determine PH of soil? I do have a ton of PH testing strips - and I even have a digital PH meter that I recently acquired for aqueous work and such?
I would assume it has something to do with the two above? but I've never actually tested PH on something that wasn't a liquid in the past.