Thought I'd post a couple of shots of pink flowered O. polyacantha variety polyacantha. These two plants were collected in Wyoming. Note the longer spines on these clones it is not uncomon to see the spine length increase, the further south you go in their range.
The first photo shows the longer spine. This clone blooms a magenta pink color and was collected in Cheyenne, Wyoming.
This plant was collected near Medicine Bow, Wyoming.
From the High Desert Steppe
of the Great Basin and the Eastern
Escarpment of the Sierra Nevada Range
Located in Reno/Sparks,NV zone 6-7
John P Weiser
That has some good color. 8)
Dry garden, little irrigation, 9" precip
Shoshone Idaho USA. Zone 5b-6a
Hot and dry in the summer, cold and snow in the winter.
John, does any of your O. polyacantha set seed? - and do you sell ;)
Rogaland, Norway - with cool, often rainy summers (29C max) and mild, often rainy winters (180 cm/year)!
TrondI do not save the seed. I would if I knew people wanted them. They can be hard to germinate.
Here is information about germinating them from Dr Deno's "Seed Germination: Theory and Practice"
Opuntia (Cactaceae). Seeds are in a fruit and were WC.for 7 d. 0. tuna germ 70D GA-3(5/40 in 8th w) and 70D(none), but the seedlings quickly rotted.Extensive experiments on 0. phaecantha have failed to give a single germination although this species self sows here. It is significant that seedlings appear years afterthe plants-have been removed. Some germination was obtained immediately at 70 for 0: aurea,. humifusa, imbricata, leptocaulis, phaecantha, polycantha, rhodanthe, and rutila, but these were qualitative experiments performed twenty years ago. It has been reported that cactus have impervious seed coats. Extensive experiments on 0. phaecantha showed that at least for this species impervious seed coats are not the problem.Some sources on germinating them say that four-five year old seed, germinate at a higher percentage rate than fresh seed. Every year I send pads to cactus gardeners around the country as trade items. That is how I have collected the plants I grow.
Probably it had been too risky to send pads to Norway ;DBut if you once take the trouble saving seed I would like to try some!
This next group of O. polyacantha clones are from an unrecognized variety. Variety rhodantha falls under the umbrella of variety polyacantha, since it has never been validated by a published botanical paper. Dave Ferguson, Curator of the Rio Grande Botanical Garden, Albuquerque, MN, has communicated to me, that he believes, it would have a good chance of attaining varietal standing if such a paper were published. These unrecognized 'rhodantha' clones tend to have thicker pads, with heavy, stout spines than are found in other O. polyocantha varieties. They are found in the areas of the Colorado River drainage of Utah, north into southern Idaho. Dave noted that, in Utah, the closer a clone grows to the Colorado river the more oval and elongated the pads become. I am assuming, this gradual change in pad shape would be a sign of genetic specification rather than environmental influences. This trait can be seen in the last photo of this post.
This clone is from southern Idaho.
This is also an Idaho clone. The flower color is unique, it is a translucent pink with lime green mid ribs.
This clone is from Utah and shows the elongated pads found along the Colorado river area.
Opuntia polyacantha is very easy from seed. I sow them in late fall inside the unheated greenhouse. Now and then during winter I put snow on the pots. It melts and feezes. I have good germination in early May - june. Allways use mineral soil and no plastik cover. As much sun as the grown up plants but that particular thing may be different for you people down south. Remember that most opuntioids are very thirsty but dislikes standing air and organic soil.
MartinI will give it a try, yet again. I just do not have any luck germinating them. I use the vernalization method and sow them in the fall on a mineral substrait. We get freeze thaw cycles almost every day in the winter. I would expect the dormancy of the seed to break at some point but have not hit the right combination. I guess. :-\
How deep are you sowing the seed? I cover the ones, I've tried, about three times the thickness of the seed.I assume you do not nick the seed coating either.
I dont do anything with the seed no. I alway cover the seed in the same depth and the thicknes of the seed. So that would be one time and not 3. Btw,you have some stunning plants!
Here's a polyacantha that originally came from Intermountain Cactus. I forget the name given to it.(The picture is framed so there are reflections.)
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