Well, you might want to hop over to the gesnariad forum, but there are some very knowledgeable folk here also. If it grows like a standard strep and is properly cared for (and under lights), it should be ready to bloom in a couple three months or so.

However the leaf will get really large and develop a root system to support it, so you may wish to re-consider waiting.

Though some folks say otherwise, I can't imagine keeping one in the same soil for that long period of time-at least as a young plant.

I repot my streps immediately after receiving them, and when small, about every three weeks (just soil freshening) until they're up into a three and a half inch pot. If they're slightly root-bound they bloom better for me, but eventually still need potting up.

I wonder where one would get one of these in the US? Fascinating!

Best,
Judy

Oh, is that one of the old types like I grew about 30 years ago, where the plants flowers and dies, having produced only the single leaf in it's lifetime?

Just looked it up..yep, it's monocarpic.

Unless you just have a collector's interest in the genus, I'd surely suggest you try a strep hybrid...but good luck with the species. It's been so long since I tried one...and I don't remember what I had, that I don't know anything to tell you.

Well I didn't know that. I have the streptocarpus susan. That I got after blooming for 2 quid unstead of 8. Leaves looks bad, and now look at it!

Well I just had a quick peak. The roots are only just hitting the edge of pot. So I'll leave it till I see them in the bottom.

So if it dies after blooming, how can I delay the blooming? If it's possible?

I got mine on ebay from a UK seller. It was after seeing them firstly on rhs Chelsea flower show. Then letter in year on gardeners world, with Monty Don.
So I wanted an unusual one. And a single leaf is most certainly unusual.

So what should the final pot size be?
I used peat for the soil.

And it's great to watch it grow, had it about 2 months, it has gone from 3" long to 7"

It actually dies after it blooms? But I saw great huge ones on line at some botanical gardens!

Still I'd love to have one just to see what it does!

Best,
Judy