Opuntia seeds - update.

[MalcolmP2]

We have seedlings

I bought a (decorative?!) pot of unknown Opuntia pads and fruit in my local veg/flower shop in early April and sowed some of the seeds. (see my first post in Introduction)
Some were sown directly out of the fruit, some others I gave a 'flash' of sunlight for an afternoon and then sowed them in the same mix as the others.
I have read some time ago that this flash technique can be beneficial to germinating (some?) seeds, even quite a short duration can be effective. I have no experience with cactus seeds, let alone opuntia, but thought it was worth a try.

That was on the 11th April, , , not a lot was happening, , , I was a bit lax on checking, , ,
by the 25th May surprise, I had three (leggy !) 'flash' seedlings.
No 'control' ones.
But 3 of 15 cf 0 of 15 is not really statistically significant

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Fast forward to yesterday and some more are coming up. 9 total so far and all are flash, still no control, This is looking more significant !

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The 3 originals are still at the seedling leaf stage, very slow to develop. No sign yet of anything growing in the junction.

[Echinocactus123]

Looks really good, I find opuntia very hard to grow from seed.

[MalcolmP2]

hard to grow from seed

I had read lots about the difficulties of germinating opuntia.
When a few weeks went by and nothing was happening I was not surprised and so I put some more in a vinegar treatment, and some in the mouldy-rot method (like what is common for tomato seeds), and some in the soak/dry/soak routine,
all in reserve and not yet sown.

[MalcolmP2]

Two months on from sowing and I think I have my first 'true leaves' (? cactus) in the junction of the 2 seed-leaves, it is an odd looking cluster though.

This growing cactus from seed lark is all new to me
I was beginning to get a bit impatient when after a month since the seed sprouted and showed its seed-leaves nothing much was happening. So I took a risk and put them out in the recent full sun. Seems to have done the trick !

[Tony R]

Well done, Malcolm.
In fact, Opuntia in the strictest sense are relatively straight-forward to grow from seed. It's the smaller opuntias (tephrocactus, cumulopuntia, maihueniopsis, etc) which are much more troublesome to germinate.

Unlike many Cactaceae seedlings, Opuntioideae seedlings start as a long root with a very visible pair of cotyledon leaves which then provide the sustenance for the stem of the plant to develop. Only much later will the top of this cylindrical stem evolve into the typical flat-pad of the opuntia.

Here is a picture of some O. robusta seedlings a little further on than yours.

If you buy an opuntia plant you can usually tell if it was grown from seed (evidence of a stem) or was a rooted pad (no stem).

[MalcolmP2]

Thanks for the info on the stem, I didnt know that.
I was very tempted to re-pot them to bury them up to the cotyledons thinking that they had become elongated through lack of light.
I'll leave them be for a while then !

Tephros etc look a very interesting bunch, for laters

[MalcolmP2]

Here is a picture of some O. robusta seedlings a little further on than yours.
Picture1.jpg

PS. a great pic !

yes, a little further on,, and much larger 'wings' than mine I think, what size pot is it and what age are they ?

Thanks.

[Tony R]

Two inch sq. pot, probably 4-6 months old some years ago.

[RAYWOODBRIDGE]

Tony you cannot possibly need more O. robusta

[ragamala]

Tephros etc look a very interesting bunch, for laters

Over the last three years I have had some, but not a lot of, success in germination Tephrocactus seed. Nothing I tried seemed to make much difference to poor germination rates.

This year I just sowed and treated as normal, and I had fair results. Perhaps this is quality of seed (from Hobby Brno for the first time).
Anyway here is a tray- sown 25th April, and first germination mostly between 2nd and 6th May. Seedling progress varies....