The lifespan of the tuberhybrida begonias can last for severalyears PROVIDED they break dormancy in the spring, have a good growing season, and are allowed to go dormant again in the fall when their light source lessens. Whether or not they bloom has nothing to do with their age, if your tuber hasn't bloomed likely you need more light during the summer growing season, or a stronger fertilizer, maybe they broke dormancy late and couln't play 'catch up' successfully. All growing is experience and observation and you asked a good question.

I don't dig them up because I had bad luck doing that, so they stay in the ground. It has a lot of leaves but no flowers, so its not really dead, but maybe it too old to bloom. A few years does not sound like a decade. You see the one that is not blooming? That is the old one, the new one is blooming so same conditions, same locations. This is very strange.

This one has a pretty orange sherbet sort of color, but I don't know if it has a name. I had a lot of Antonelli Brothers begonia, but most of them were stolen from in front of house. I had a red one that lasted a few years, but it came back smaller every year. I will post the orange one and the red one. The red one has not come back for a few years.

Your non-bloomer looks very healthy. I think you need comments from growers who actually grow them in the ground, I don't.

Do you have a green house? That must be a lot of fun.

I fed it with dyna grow, but I still wonder if it's having old age problems, since it's my last one from Antonelli Brothers.

The life span of tuberous begonias is up to 30 years. Blooming of the begonia can degenerate over the years due to old age. Your bulb should not be experiencing diminishing blooms. It's likely the bulb may have some form of disease or it may be an environmental factor.

Antonelli Brothers Begonias was acquired by Golden State Bulb Growers in 2010. Golden State has crossed some of the Antonelli's begonias with the AmeriHybridî begonias, producing far more vigorous hybrids.

CalBegonias.com is where you can purchase AmeriHybridî Bulbs.

Here is a link that might be useful: CalBegonias

wow, these are begonias worth growing! click on 'begonia buzz' to see some new antonelli hybrids.
I got some nice tuberous ones at bot garden - they never even come close to 'package pics'. semi-doubles reduce to single. even some of my non-stops are not blooming that well, even though some years ago they bloomed fine (diff plants).
I wonder if i'll be able to actually bloom these well, if I order?
does anybody have them?

I only got pots on a NE balcony, so I get max 4 hours of early morning sun (till 10 am). I know they don't like heat, so I take them indoors when it's over 80-82F and keep them inside until temps drop, then out again.
sometimes it's just a few weeks indoors, sometimes more.
the lighting inside is super bright: 2 corner windows NW+ NE and glass top to bottom the whole wall - it's like a sunroom. get may be 3 additional hours of filtered western light. about 72F-75F nite/day inside.
for soil I use african violet soil + sphagnum peat + perlite in equal proportions in tallish pots (size like large yoghurt containers 1.5qt), but I also uppoted some to 8" containers when they got bigger.
so, definitely not half-day of sun (6hours?), no compost in pots. but petunias bloom in same conditions - so I figured there should be enough light?
the non-stops do bloom, but flowers are not as well formed as they should be. so probably no hope for the large-flowered varieties?
I feed them AV 7-7-7 fertilizer with every watering. and start giving them Schultz AV fertilizer for blooms (8-14-9) once they get buds.
keep them just moist, no wet, no drying up, just slightly dried on the surface, then water some, but no drenching, no water running from the bottom. just enough to keep even slight moisture in the pot.
have you grown them in pots ever, or just in the ground?
what nite temps do they need? what temp drop between day/nite? may be my nites are not cold enough?
sorry to swamp you with questions, but I can't find enough specific info anywhere. ready to give up even with non-stops - too disappointing.

I don't use pots because I am not lucky with pots. However, using als gritty mix does work, but still the ground is better. I use compost made from food waste and starbucks coffee grounds and bagged sheared wood. But, compost does not work in pots. I think it's the compost, but on the other hand, Antonelli Brothers did great in pots. They used a green house environment and feed them with Romeo brand food the red colored one. One tip is avoid wetting the leaves as much as you can, for fungal problems and they did spray them with fungicide and they used small sticks to prop up the larger flowers. Doubles can sometimes droop or break off. So clearly compost and the ground is not a requirement. I would order at least one double and try it. I found ones I just buy like at any old place like home depot wonâÂÂt be up to par at all. You have to be on top of the small sticks/stakes because as it get bigger it will begin to sag and then break off, so you need to stake before it sags. They use small green bamboo stakes cut up to the size they want. They do not need a cold night, they donâÂÂt actually like cold. I could be wrong, but we donâÂÂt get cold nights here in San Francisco, normally 50âÂÂs. If you can, increase the humidity, because sun rooms can be dry. They like humidity, but then you donâÂÂt want wet leaves, just humidity in the air. Water deeply until it runs out of the pot, but then donâÂÂt water until it is dry again. You want to flush out any salts from the pot. If you only water just a bit, the salts from the fertilizer can build up. I would repot often if possible. I am not feeding mine with the romeo stuff, since I have so much compost, I use dyno grow foliage, because I have alkaline soil and water and they like acid soil. If you feed with a high middle number which is good for flowers you risk increasing alkaline soil. Your soil choices sounds ok for a begonia, I donâÂÂt have enough experience to judge, but the peat moss can get packed down so maybe some perlite? They appeared to grow them in peat with perlite, and I mean, a lot perlite, as I recall. I also use treatments to increase the acidity sulfur is good, it is also a plant food as well. Or aluminum sulfate, but donâÂÂt use too much. When you repot look careful at the tuber and check to see it is firm and healthy. If it is soft the plant is rotting. You can sort of get the hang of how a healthy tuber looks, itâÂÂs like picking a good potato, not rock hard, but not mushy. Then always make notes on what you did so it something works better you can do that again. I got the orange one to bloom but it is just a later begonia then the other one. It has big flowers, I took a photo today of it.

that orange color is fabulous! what size are your flowers?
by our standards sf nites are always cold;). looked up you weather...and you have 55-60 nites! in aug...and 70-75F days. yah, isn't it the optimal for begonias? I heard that cape cod and nova scotia are absolute begonia heaven.
my nites reach 70F in july-aug. and indoors I don''t go below 72F. I tend to think that's my problem.
if I could do 65F nite I bet they would love it. but I can't.
thanks for the tip on romeo, I checked red it's 15-30-15.
so mine is half as weak as yours. i could double up the dosage though! I used to use Schultz orchid fertilizer 19-31-17 on non-stops, then I ran out. they bloomed better then (and it was a cooler summer that year).
I have hi humidity indoors:75 to 80% summertime, while this summer it's been dropping to 50% outdoors almost ev.week. that could be a factor.
may be I should try blooming them completely indoors?
it seems to me my indoor conditions are better then outdoors for them, except light intensity.
I have caladiums going really well every year totally indoors.
my soil has prolly about 40% perlite, since AV soil has some and I add 33%, so that should be ok.
I also have dyna-grow 10-5-5 that I use on other plants with every watering.
I give them miracid 30-10-10 may be once a mo too.
i am going to do an experiment. when nites drop to 55-60F i'll bring them in for the day to a sunny west window (i know they like that, i start tuberous there), but then put them out at nite. see if they perk up. oct will be too late for flowering though, no?
when do yours stop blooming?

Actually you must be thinking of the east bay area of Oakland, because we have cold summer with an average of maybe 65, but often low 60s during the day and 50s at night. Cape cod does sound good for them because of the humidity. Maybe they are being over fed with too many different types of food. I just don't know container growing well at all. The stop blooming in late October and kind of die back. I have been keeping them in the ground all year, because if I dig them up, they sort of begin to rot in storage. Since I lived here all my life, I am sort of out to sea when it comes to other climates. Plus there are micro climates in san francisco, I live in the so called fog belt area.

If you want bigger flowers one problem is if there are too many flowers they are smaller. This year that one has bigger flowers that are three inch, but that is all it had, but now it has some new flowers, but those will be smaller. I know some people remove some of the buds before they break to make those bigger ones bigger, but you sacrifice volume of flowers for size of blooms. This is the biggest I had for this plant, I did not think it would flower at all, then it came up with just three, but they turned big. It varies year by year. I add some new fresh compost, also, a few weeks ago.