Grow little buddy, grow!

March 7, 2008 1:45 PM

How do I get started with germinating cactus seeds?

Hello. I love me some cactus. I have one growing right now and its awesome, but I bought it as a plant, not as seed. I'd like to get started with germinating cactus seeds, but I'm not sure about the best way to do it. Some caveats:

1) I live in Canada. So, uh, I don't exactly have a lot of warmth outside. Especially not now.
2) I'd *really* rather not use grow lamps or other heat sources. I do have multiple old school radiators, so I could probably use them, but I don't want to have a huge power drain. If there's some wicked awesome low power drain lamp solution that I don't know about, that would be nifty.
3) I don't have a yard, so this would be pots only. None of my windows get a hell of a lot of sun.

Oh and yeah, if you've got a nice reputable place where you buy cactus seeds and garden stuff in general (I'm in Hamilton, ON, but can tool around the GTA if need be) -- please let me know! Recommendations for particular species to grow are good too.

posted by the dief to sports, hobbies, & recreation (7 comments total)

Many cacti are commonly grown from cuttings. If you can find someone else who shares your hobby, they might be able to provide you with some.

These folks have some seeds for sale. There are a few cacti on that page, although it's captioned as having trees and shrubs. There are some mean shrubs out there.
posted by yohko at 2:36 PM on March 7

For heat, do you have a dsl modem? Ethernet switch? expressvu receiver? Wait, you said hamilton? Ok, scratch off the expressvu and substitue viewsat or pansat. All of those are great for germinating seeds in my experience.

Also, as you're not starting out with a ginormous cactus, but growing from seed, a ~27 watt compact flourescent on a timer should work for seedlings - you might have to get creative to have the light close enough (4-12 inches). You can grab those at Rona, Home Hardware, Fortinos (oh, how I miss Fortinos compared to Zerhs... could you have a Roma pizza tonight for me? nom nom nom), or just about anywhere.

(note: I haven't grown cacti from seed myself, but I'm grown other plants (next up is kudzu!) from seed by using surplus heat from electronics and flourescents for seedlings)
posted by nobeagle at 2:44 PM on March 7

Unless you have a good, strong unshaded southern exposure, you're going to want grow lights. You don't need anything fancier than a simple fluorescent fixture, though this isn't a very attractive option.

Cacti will grow in less light but their growth will (generally) be spindly and weak. Not something really nice to look at.
posted by jeff-o-matic at 2:51 PM on March 7

Also, as long as this is in normal room temperature and not cold, you're not going to need to boost the heat at all. Cacti need a lot of light, but room temperature is fine.
posted by jeff-o-matic at 2:54 PM on March 7

nobeagle, I have a wrt54g. Is that sufficient do you think?
posted by the dief at 2:55 PM on March 7

I've never grown cacti from seeds, but I have grown a lot of other stuff. You can buy a heated propagator, but I've no idea how much energy they use.

The only real advice I can give is this - let the seedlings dry out slightly between waterings. It seems counterintuitive, but there isn't often a stable water supply in the desert (this is assuming you're growing desert and not forest cacti - small lumpy ball shaped cacti (think Mammilaria or Ferocactus) are probably desert growers, while trailing cacti (think Christmas Cactus, or Epiphyllum) are probably forest dwellers). Letting the seddlings dry out slightly apparently encourages stronger growth, because the plants try harder to conserve water.
posted by Solomon at 3:17 PM on March 7

re: wireless router. I don't have your specific model, but put your hand on top of it. If it feels warm (not hot), it will be good for germinating. Once you put them in soil you shouldn't need the heat; just light. And the number of hours of light is important. For seedlings that you want to grow, find the number of hours of light they'd get naturally in spring. Likely 16-18 hours depending on location.

I definitely second Solomon's advice about letting them dry out between waterings - if the roots have to work; they'll spread and stretch and the root system will become stronger much more quickly.

I have three cacti (inherited from my FIL) and I'm in a similar location as hamilton. He had them for 7 years in a east facing frosted bathroom window. I kept them there for another 3 until we moved. Now they're in a south facing sunroom, and they've noticeably sped up in growth. However, if I'd kept them in the same consistent non-great light, they'd look small, but not odd. Now two are like snowmen standing on their heads. The third, which has a structure rather tree-like looks non-odd to me.
posted by nobeagle at 4:02 PM on March 7