One Seed Growing Approach
Posted: Wed Aug 09, 2006 12:30 am
Hello-
I've had some success with the following seed sowing and growing procedures, so I figured I'd post it. I'd also be interested to hear what others have done that either worked or didn't.
My methods are fairly labor intensive up front, but make it possible to grow the germinated plants generally just like all of my other plants after a few months.
The mix:
2 parts coarse construction sand, screened to remove bigger rocks etc.
2 parts fine red scoria, a volcanic pumice available here in NM. This has to be screened three times, until it's uniformly about 1/8th to 1/16 of an inch across. Tiny little airy rocks. Substitutes could be perlite, other forms of volcanic pumice, or perhaps a fine gravel.
3 parts Metromix 320, a soil-less commercial mix, also screened to remove bark, etc.
Some species get no Metromix at all (Sclerocacti, Pediocacti, some Astrophytums, Echinocacti, etc), but the heavy sandy fine loam we have here on the mesa tops. In other areas I suspect sand, perlite and a small amount of any growing medium or loam would work.
The sand and scoria is baked in an oven at 375F for 45 mins to an hour.
A note on screens: several different size window screen material is available from hardware and home improvement stores. Generally, a wide, a medium and a small work fine, and can be nailed or stapled to a simple wood frame.
Sowing:
It's important to thoroughly mix the ingredients, so that water absorption and retention is consistent over the whole lot of pots.
I like to use individual 2" green plastic square pots, so that species with different requirements can be treated differently after germination if necessary. I also sometimes get lazy and use "plug trays," with a preference for the larger size compartments. Plug trays aren't so great when you sow a bunch of Echinocerei right next to the early rotters like Astros and Echinomastus, etc.
I fill the pots or plug tray evenly and then soak, as in soak completely. I am not particular about water, but probably should be. But even just with regular tap water I get good results.
Sprinkle the seeds as evenly as possible over the soil surface, about 10-30 seeds to a pot. The seedlings and young plants are going to be in these pots for about two years, so I don't like to sow too densely.
I cover only to the thickness of the seed with some of the coarse sand, or sometimes some fine gravel. I've found thinner covering to be better than too much.
I use a seed tray with a dome cover. It stays on fairly tightly for the first week or two and then gets propped as germination proceeds. I also overhead water with a fine mist attachment, and have never had any loss or washout or anything. Some strongly recommend bottom watering, but the foggit nozzle on the hose works fine for me. I spray lightly two or three times a day for the first 10 days or so. Generally, I've found cactus seedlings appreciate moisture and humidity. If you can provide hot (85-100F) days and cool nights (65-70F) most species seem to appreciate this also.
Light: I sometimes put the seed tray(s) outside where they can get bright sun, but put shade cloth over the tray dome, propped up. ("Shade cloth" this year amounted to a few Bounce dryer sheets).
The trays also sometimes just hang out in a bright window without direct sun and with no shade cloth.
Santa Fe nights can be a bit too cool, so I used a bottom heat pad this year and it seems to have helped.
After a month or two I just spray water once or twice a day.
The first winter or two the seedlings stay fairly moist.
Anyway, this is what I do, without a greenhouse. I think what cut down on success in the past was actually too little moisture. I guess I prefer overhead spraying because you can control the amount of water delivered more carefully. The trick seems to be to maintain (for most species) a consistent, even moisture that's not too wet but never completely dries out.
Hope folks find this helpful,
Peter
I've had some success with the following seed sowing and growing procedures, so I figured I'd post it. I'd also be interested to hear what others have done that either worked or didn't.
My methods are fairly labor intensive up front, but make it possible to grow the germinated plants generally just like all of my other plants after a few months.
The mix:
2 parts coarse construction sand, screened to remove bigger rocks etc.
2 parts fine red scoria, a volcanic pumice available here in NM. This has to be screened three times, until it's uniformly about 1/8th to 1/16 of an inch across. Tiny little airy rocks. Substitutes could be perlite, other forms of volcanic pumice, or perhaps a fine gravel.
3 parts Metromix 320, a soil-less commercial mix, also screened to remove bark, etc.
Some species get no Metromix at all (Sclerocacti, Pediocacti, some Astrophytums, Echinocacti, etc), but the heavy sandy fine loam we have here on the mesa tops. In other areas I suspect sand, perlite and a small amount of any growing medium or loam would work.
The sand and scoria is baked in an oven at 375F for 45 mins to an hour.
A note on screens: several different size window screen material is available from hardware and home improvement stores. Generally, a wide, a medium and a small work fine, and can be nailed or stapled to a simple wood frame.
Sowing:
It's important to thoroughly mix the ingredients, so that water absorption and retention is consistent over the whole lot of pots.
I like to use individual 2" green plastic square pots, so that species with different requirements can be treated differently after germination if necessary. I also sometimes get lazy and use "plug trays," with a preference for the larger size compartments. Plug trays aren't so great when you sow a bunch of Echinocerei right next to the early rotters like Astros and Echinomastus, etc.
I fill the pots or plug tray evenly and then soak, as in soak completely. I am not particular about water, but probably should be. But even just with regular tap water I get good results.
Sprinkle the seeds as evenly as possible over the soil surface, about 10-30 seeds to a pot. The seedlings and young plants are going to be in these pots for about two years, so I don't like to sow too densely.
I cover only to the thickness of the seed with some of the coarse sand, or sometimes some fine gravel. I've found thinner covering to be better than too much.
I use a seed tray with a dome cover. It stays on fairly tightly for the first week or two and then gets propped as germination proceeds. I also overhead water with a fine mist attachment, and have never had any loss or washout or anything. Some strongly recommend bottom watering, but the foggit nozzle on the hose works fine for me. I spray lightly two or three times a day for the first 10 days or so. Generally, I've found cactus seedlings appreciate moisture and humidity. If you can provide hot (85-100F) days and cool nights (65-70F) most species seem to appreciate this also.
Light: I sometimes put the seed tray(s) outside where they can get bright sun, but put shade cloth over the tray dome, propped up. ("Shade cloth" this year amounted to a few Bounce dryer sheets).
The trays also sometimes just hang out in a bright window without direct sun and with no shade cloth.
Santa Fe nights can be a bit too cool, so I used a bottom heat pad this year and it seems to have helped.
After a month or two I just spray water once or twice a day.
The first winter or two the seedlings stay fairly moist.
Anyway, this is what I do, without a greenhouse. I think what cut down on success in the past was actually too little moisture. I guess I prefer overhead spraying because you can control the amount of water delivered more carefully. The trick seems to be to maintain (for most species) a consistent, even moisture that's not too wet but never completely dries out.
Hope folks find this helpful,
Peter
