Echinocactus polycephalus v polycephalus seed starting

[cactoman]

Hi all...

Does anyone here have any pointers at all for getting these very difficult seeds to get going? I have a batch of habitat seed and some new ones coming from MG. Any info for this seed starting newby helps.

Thanks, Ed J
the CACTOMAN

[daiv]

Hey Ed, a couple members here have grow these from seed - even in England! They will no doubt chime in soon, but in the meantime click on the "Search" link in the gray bar above and do a search on polycephalus - you should pull up some good info.

[promethean_spark]

They seem to germinate fine, but don't survive well over the long term. The seedlings are quite large though, so I'd suggest grafting them ASAP on a long lived stock. I have one on pereskiopsis that's 2 years old and ping-pong ball sized. I have some over a year old on their own roots, but I've had 80% losses. I have 3 2 year old var xeranthemoides, from 10 mesagarden seed (all that hatched), they're much less tempermental.

If you do want to try growing them on their own roots, you should research the rain/temp patterns of the area your specific seed comes from. Their range is kind of at the edge of the winter-rain area of CA and the more standard winter-dry deserts of AZ and NV.

[peterb]

I'd agree with the numbers: about 30% germination and roughly 70-80% mortality on their own roots. Haven't found anything that works to get more to sprout or survive. The ones that do survive the first year or two seem to do well, however.

Mineral mix, nothing organic in it whatsoever, great drainage. Plenty of sun and warmth. The one I still have going (no jinx!) from Inyo Co. California loves rain over the winter here in warm-ish Phoenix.

Promethean, aren't they all from deserts that get winter rain?

peterb

[iann]

I find germination is very easy, but only for a small percentage of seed. I'd say about 20% just pop up with no difficulty at all. I've even had them sprout on the same day they were sown! Nothing I've tried persuades the rest to germinate well. It is worth noting that the vast majority of E. polycephalus seed will be directly from habit since these plants are not easy to flower in cultivation, so 20% perhaps shouldn't be considered so bad.

My experience has been that the seedlings are robust and hardy. I have only ever killed one despite all my experiments of subjecting them to extremes of temperature and watering. If I had killed more I could perhaps give you more information about what conditions they don't like. I can tell you that they are cold hardy, certainly to 20F (-7C), and probably a little colder. They are among the more sun and heat resistant cacti that I have although none of mine are by any measure mature adults.

No new spines yet this spring, but they're all nice and fat now. Nights still around freezing, days have been warm but not hot (in the greenhouse).

[Tony]

My limited experience has been roughly the same as the others, with a low germination rate no matter what I try, wet/dry cycles, scarification, sand paper, etc.
The ones that do germinate, continue to grow slowly but surely. I watch them carefuly and water them when they are obviously growing.

I currently have a pot sown in Nov/2010 with 20 habitat seed, (lucern valley)
4 germinated right away with no treatment other than soaking, the rest are just sitting there.

[Hanazono]

I bought 20 seeds of E. polycephalus f Las Vegas Nevada and sowed in 2006. I did not do any special treatment but the germination rate was around 50%.
It was better than horizontalonius.
I grafted 3 seedlings and kept others as own-root.
Grafted ones are around 10 cm diameter. Own-root ones are glowing very slowly. They are just 3cm diameter but all of them have survived.
Hanazono

[promethean_spark]

They're in the transition zone from winter rain to summer rain.
See:
Las vegas
http://www.weather.com/outlook/health/f ... h/USNV0049
Death valley (where my var polycephalus are from)
http://www.weather.com/outlook/health/f ... h/USCA0286

They get more summer water than I do! Note that Las Vegas gets pretty much 1/2" per month except for April, May, June, which get ~0. April/May/June is usually a time that folks consider safe to water almost everything, winter growers, summer growers... Also notable is that the Las Vegas plants get 3x the water of the death valley plants in late summer. They should be more forgiving, which my v. xeranthemoides are (from 30Mi east of las vegas).

[RobR]

I agree with the others that mortality is high. I have had my best germination when I sow the seed outside during the AZ monsoon season for the heat/humidity. Mineral type soil with the pots under shadecloth. I have had good luck getting them going but the die-off comes quick. Will try again this year as I did get a batch of seed from a location in SW Arizona.

[cactoman]

Also...I have a batch of this seed that is about 6-7 years old...should it be any good at all anymore?

Thanks

[peterb]

Re: winter rain:

The Death Valley average rain stats are amazing. If my figures are right, the average annual rainfall is only 2.33 inches. 50% of that rain comes in Jan/Feb/March.

The Vegas stats are remarkable as well. I didn't realize Vegas is that dry (an average of less than 5 inches of rain a year). Slightly more than 40% of that rain falls in the winter.

It should be noted also that the quality of the winter rain is quite different from that of the summer storms. In summer, the rain blasts down very quickly and runs off, then dries very quickly as well. In winter, the rains are steady and soaking and can last for several hours.

Not sure what you mean by "the transition zone from winter rain to summer rain." 40-50% of the annual total rain falls over a three month period from Jan-March. This may or may not be significant in cultivation, however. I don't know in any conclusive way if polycephalus grows over the winter. I suspect the cool, "wet" winters might serve some highly necessary purpose for the roots.

What is definitely significant is the dry spring you mention. Most of my polycephalus catastrophes have occurred from too much moisture in spring.

In general, I think the relevance to successful cultivation of the temperature and precipitation cycles of the habitats for polycephalus and Sclerocactus polyancistrus, Echinomastus johnsonii, etc. and a few other forms is not very clearly understood.

peterb

[iann]

6-7 year old seed should do well. Maybe even better than fresh seed. Provided it hasn't been stored badly.

So I said seedlings are "robust and hardy", but I have some that aren't. I sowed a batch of seed from Helendale, CA, which is a bit of an outlying population. Not much summer rain there! The stats show some, but I suspect it is one thunderstorm every 5 years.

I noticed that the seed was a little smaller than normal and the seedlings are a lot smaller. Or they are a lot slower growing. Maybe the ones from SW AZ will also show differences.

[promethean_spark]

Here's rain data for bakersfield, which is similar to the 'winter rain' paradigm for most of CA.
http://www.weather.com/outlook/health/f ... h/USCA0062

Almost no rain from June-Sept, whereas the Ecac-poly habitat has no rain from April-June. Instead of summer-dry (since it rains 3/4 of the year), it is spring-dry, which is why I consider it a transition zone from 'winter rain' to 'summer rain'. As you go farther southwest, the rain gradually falls more in late summer, and less in winter.

[peterb]

Ah, I see now, thanks. "Spring dry" makes a lot of sense, thanks.

peterb

[iann]

Here is a seedling from Helendale. I increased the daytime heat for the last couple of days and it has got stronger. Or maybe it would have grown anyway.


And here is one from Baker that germinated on the same day. This is only around 60 miles from Helendale but I think you would say it is part of the main habitat area for the species.