The ones I started from tubers are being slow this year The ones I started from seed have been blooming for a while. Are you using a fertilizer meant to encourage blooms? (with a high middle number?)
Ruth

I have actually have not used any fertilizer on them. I suppose I should.

Thanks
Jenny P

I planted lots of double Begonias bulbs at the end of April in containers,I am left with just large bushy green leaves which look healthy,but they are not flowering,will they flower,or should i just dig them out.
Thank you.

I stopped in at Aladdin Nursery last week. One of the Antonelli Begonia people works there now. I bought a couple of tuberous begonias, a fuzzy cane and some fuchsia. He told me to use an even numbered soluble fertilizer on my tuberous begonias every two weeks,'it helps'. I have started that routine. I have noticed that I am getting smaller flowers then the first flush of blooms. I am testing the theory that I get a big flower first from stored up energy and that flowering is depleting my tubers. If I fertilize I can build energy for next year.
I have 'On Top' tuberous begonias in a flower bed under a Japanese maple tree. The first 2 rows are blooming well and the last row have good foliage and no flowers. I am guessing the back row have too much shade. I am not doing a thing about it. May was too cool and wet. It went form 70s to 100+ in a week. We are suffering through another long string of 100+ days. Too bad I'm not into cactus!

In our high altitude (3600')August is the big blooming month. If you bought tuberhybrida as (Non-Stop) starter plants from a nursery they are usually blooming when you get them. My Pin-up Flame grown from seed bloomed very early on, makes me wishthe others could or would do that.These plants originated from 7 plants all growing in the Andes, so cool growing conditions are supposed to be their thing.I guess we just have to be patient.