[Blackpool rocket]

Hi all,
I bought some giant begonias last year. I have saved the tubers, they're in the garage somewhere 
How easy is it to propagate from the tubers, or a leaf?
I have done a quick search but really wanted some first hand experience.

Thanks

Br

[Kristen]

Plant the tubers (dome shaped side upwards) on the surface of some compost, almost no water - compost "just" damp - and stick them somewhere hot. Airing cupboard or boiler room until they sprout and then put then in the light.

If they were just "chucked in the shed" they might have rotted over winter though ...

When the leaves are growing strongly you can propagate from leaf cuttings. Its a slow process though ...

[Goosegirl]

Kristen - is it dome-shaped upwards or down? I thought the roots came out of the bottom of the dome.

[Kristen]

yeah, I meant that but described it badly, thanks.

There is a concave indentation on one side, and a convex dome on the other.  I was stupidly thinking that a "concave indentation" was dome shaped ... on reflection that's a very obtuse definition!

concave indentation upwards
convex dome downwards

[Kristen]

Sadly they will not all be as obvious as that, on some it will be hard to work out which side is the concave side



If you can still make out where the Stem was from last year that will help.

If in total double put them in some compost in a tray, with the corms half out of the compost, and when they kick start then pot them up. If you think they might be upside can one pull out and see if the stem is trying to grow out of the "bottom" and if so turn it round (or pot up if it has grown enough)

[Blackpool rocket]

Thanks Kristen, glad that's cleared up 

Is it possible to "split" the tubers in half?

[yorky]

Is it possible to "split" the tubers in half?

Yes it is. You must then give a good dusting of Yellow Sulpher onto the exposed cut or they will soon rot. Another draw back is that roots will never grow out of that part of the Corm where it was cut.

[Yorkie]

Yellow sulphur became illegal to use a few years ago.

See here for revocation notice

[Goosegirl]

Not sure if this is so, but I think the tubers get bigger each year (up to a point) so maybe you will get larger plants instead of propagating and getting more smaller ones. If you do decide to cut the tubers you could use an available spray-on fungicide instead.

[yorky]

Yellow sulphur became illegal to use a few years ago.

See here for revocation notice

Yes you are right, I had forgotten about that. Don't you just love the EU. They haven't completely banned it, you can still buy it to use as a soil acidifier and nutrient. So that's all I will be using it for in future. 

[Lesleyk]

Plant the tubers (dome shaped side upwards) on the surface of some compost, almost no water - compost "just" damp - and stick them somewhere hot. Airing cupboard or boiler room until they sprout and then put then in the light.

I have been trying a new way of storing the tubers over winter, which is to put them in individual brown paper bags.  But once they are ready to pot up, as you describe, what happens if I have nowhere hot to put them? I have quite a lot of tubers and no hot, dark space.   I was just going to pot them up in the greenhouse (unheated) but that wouldn't involve anywhere hot and dark ..... 

[Kristen]

I think that if you put them in an unheated greenhouse (and they are potted, and thus have some moisture) that they may rot.

I would delay until it is warmer.

Anywhere at work that is warm for them to start off, and no one will mind?

Friend / relative's house?  (I realise this might be a bit of a stretch?!!)

[Lesleyk]

I think that if you put them in an unheated greenhouse (and they are potted, and thus have some moisture) that they may rot.

I would delay until it is warmer.

Anywhere at work that is warm for them to start off, and no one will mind?

Friend / relative's house?  (I realise this might be a bit of a stretch?!!)

Great suggestions, thanks.  Unfortunately, I work for myself - as a gardener! So my work is also my home.  My situation is extremely remote, so no friends, neighbours or relies anywhere nearby.  I will just delay the potting up I think