Does anyone grow any of the Swertia species?
I would like to find information on seed germination of Swertia hookeri
I hope someone will respond with actual experience with this genus.
In the meantime, by Googling "swertia germination", you can find many scientific papers on germination (mainly aimed at propagation of endangered Swertia species)...
After a quick perusal, I haven't found anything on Swertia hookeri, but the info for other species may be an indicator:
Paraphrasing from the one above, "Cold stratification is required... but GA3 may or may not promote germination".
Anyway, lots more info out there to try to filter through, if you want to.
Calgary, Alberta, Canada - Zone 3
-30 C to +30 C (rarely!); elevation ~1130m; annual precipitation ~40 cm
I like "may or may not promote germination"......very useful. I may or may not have experience with Swertia hookeri, but I do (or do not) have experience with GA3, and I think it is (or is not) a complete waste of time.
Seeds of most (or all) plants for which GA3 is recommended (or considered essential) germinate perfectly well without it.
extreme western edge of Denver, Colorado; elevation 1705.6 meters, average annual precipitation 30cm; refuses to look at thermometer if it threatens to go below -17C
Thanks Lori ! I had been Googling on "Swertia seed germination" and of course all the commercial sites come up on seed !
GA - 3 may be useful for some seeds.
I have placed the Swertia seeds into vermiculite with about 330 ppm GA -3
There does not seem to be much information on the concentration to use.
I just have gone with what I had prepared. I had ordered a GA - 3 , one gram tablet , thinking I could more accurately cut it into fractions, but about one third of the tablet broke off,---- so I dissolved that in a one liter, washed, shampoo bottle so my concentration is approximate.
I am an experimentalist at heart, and must just try these things.
Lack of information on the concentration of GA3 is one of the problems, the other, a much bigger problem, is etiolation of the seedlings. Exacerbated if the seedlings are grown under lights with the wrong spectrum. (This from experience.)
Seeds that are said to have an "absolute requirement" for GA3, like echinocereus, usually don't have any such requirement.
Watch for etiolation, is all I can say.
[quote=penstemon]Seeds that are said to have an "absolute requirement" for GA3, like echinocereus, usually don't have any such requirement. [/quote]
I can at least attest to that for Echinocereus triglochidiatus, E. reichenbachii and E. viridiflorus. They germinate easily for me at 80F.
Rick Rodich zone 4a. Annual precipitation ~24 inches
near Minneapolis, Minnesota, USA
Etiolation can be a problem with cactus seedlings grown under lights, too. There's some discussion about the right kind of lighting on the Cacti Guide site.
I'm a compulsive sower of cactus seed, and have about 750 seedlings from Alplains seed, from the last three years (and that's not counting the hundred or or I gave to DBG). All of the seedlings now are in pots of pure sand, getting light from a west window. I find that echinocereus germinates in about three days, surface sown.
Talked to someone who was a propagator for a botanic garden and they said no seeds have a requirement for GA3 (applied externally, that is); it's just a substitute for stratification. Not always an effective one.
I am not trying this germination under lights other than ordinary room lights.
Eventually, any seedlings will need more light.
On the GA-3 -------not enough research has been done to know whether it works or not.
The thought has occurred to me that perhaps other less exotic acids might work just as well.
For example: aluminum sulphate is used to create acid soils----perhaps it could work for germination?