Seedlings from the "2005 seed pool clear-out"

[Stuart Estell]

This is the point at which you expect me to have written all the dates down, isn't it?

I only got into the habit of writing dates on all the labels recently. I think all of those were sown last Feb, so 11 months-ish.

[Chris43]

That's great news, Stuart. Very good ot know that some at least worked for you. The differential growth rate of the Corryocactus is quite striking, isn't it. I wonder why? You would expect perhaps some difference, because of when they germinated, maybe slight differences in soil/moisture take-up, but that really is a lot.

[Stuart Estell]

It's odd, isn't it Chris? I do remember that the two smaller ones sat there doing nothing for ages and were far slower to germinate, but only by, say two or three weeks. One of them germinated with three cotyledons, but other than that, nothing remarkable really.

[IanW]

I noticed a similar thing this year though, all my pachycereus species seedlings after 3 months had reached the size of some Trichocereus I'd had growing for 9 months.

I've found Cereus hilmannianus also had similarly fast growth, reaching 2 inches in height and looking like a proper cactus (rather than a generic seedling) 3 times as quickly as most Trichocereus sp.

[Julie]

Awww, look at the forbies! Thanks for the pic, Stuart.

There's a lot of difference in the size and stripiness on them, even at that age.

[Chris43]

I can well understand different growth rates for different species, let alone different genera. Its the difference between seed sown at the same time from the same packet.
I wonder if slower growth comes from "poorer" seed? And if seed quality will vary naturally even from the same seeed pod? If so, and it would be interesting to know from anyone if it is, then I suppose that these differences might be accentuated as the seed gets older. This could explain poorer germination from older seed, which is quite marked in some species, like the Fraileas commented upon on another thread.
Excuse my musings, as you'll gather, from a non botanist!

[Stuart Estell]

Here's a thought - I'd forgotten that I've sown another batch of Corryocactus melanotrichus from another source (Koehres) - and these are all growing like the previous sowing's "runt" seedlings. I'd assume that the Koehres seed is relatively fresh though, so perhaps there is a mysterious "quality" factor at work.

[iann]

I'm not sure that slow growth should be interpreted as poor seed. It is simply part of the variation in any batch of seed. Experiments have been done showing that seed from plants which have been cultivated for several generations germinates more quickly and completely, and then grows more quickly, than seed from habitat plants. The interpretation of this was that cultivated seed has been selected for quick germination and quick growth, but this may in fact not be helpful in habitat.

There are other interpretations of the result, but it is easy to believe that having "cautious" seed as well as "gung-ho" seed may overall be a benefit in a harsh unpredictable environment.

[Stuart Estell]

Interesting again, Ian - I believe my first batch of Corryocactus seed was habitat collected. It had a field number, in any case, whereas the Koehres seed has none.

[Susanne]

I have some Browningia Candelaris and Cereus Hildemannianis which were grown from old seed. I remember that we had a disscussion about old seed before. Some grow into nice plants despite their age. ( but yes I was never lucky with Fraileas).
I think that it is a bit of a waste to discard old seeds. I am always happy to take and sow them. Money that I get from plant sales from these seeds later goes back to the society.
So Chris if you have old seeds let me know I'll take them.