What are they in and where's the container located? If there's no organic matter, then they'll need some food. A few drops per plant should be enough to get them to respond, though you might need a magnifying glass to see the results. Some photos of what you've got already would be helpful.

Astrophytum, iirc, come up and start looking like adults quite quickly and then may slow down (to put down their taproot, perhaps). A reddish colour signifies strong light. A pinkish tinge is fine, but a deep red is not so good unless it's on the older / initial growth unprotected by spines.

I've started a few seeds in an enclosed environment and in a purely inorganic mix with a weak dose of fertiliser. The plants are now about a year old now and smaller than they 'should' be, but they have the right shape for their age.

My seedlings are growing very slowly too! I planted these Aloe ferox in March or April and they are still only a couple inches tall. I have been told they should speed up after about a year and a half; hopefully yours will do the same!

These are now in a smaller pot together, but this is what they looked like before I moved them:
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The cacti are in plastic pots with half "cactus soil" and half perlite. They are under fluorescent lights. I can't remember what the cactus soil had in it, I'll check tomorrow. The little tiny cacti have small spines and I can see that they are starting to grow something on top of their seed leaves, something more cactus like, so that should be good. If the soil does have organic matter, how long should I wait until I fertilize?

Thanks for the info!

Hey, couchpotato83, those aloe look great! Good to hear that our plants should speed up in about a year. :) keep us posted on those little guys!

Taryn :)

Cactus seeds do grow slow after the initial come up...from what I understand cacti do not need fertilizer, they do better without it. Cacti grown hard tend to last longer and grow better because they are stronger. That does not mean they look prettier but they are sturdy and strong plants and will flower and produce fruit that is strong and seed that will pass on the same quality. Not sure I said that right as words sometimes fail me, but I think you get what I mean.

Mary

Thanks, Mary! I get what you mean. I'd rather have strong plants rather than pretty ones. :) thank you everyone,

Taryn

Hi everybody!
I collected some seeds from my Rebutia Muscula this summer and planted them about 1-1,5 months ago. This is the biggest one so far, you can just make out some spikes on the top! :-D

/Sofia

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