Dahlias from seed

All I can find to read about dahlias talks about them as tuberous plants and most of the queries about cultivation concern the tubers. For the first time this year, I have grown some nice "Bishop's Children" from seed, these are described as annuals. Are these true dahlias? Would they produce tubers? Do all tuber dahlias start off from seed? Why bother with the tuber palaver at all? Could someone shed a bit of light please.

 

Hi cr1tical, I'm sure I've dug out "dwarf bedding dahlias" before now that had developed tubers but threw them away as next year's box of 6 were not expensive. But, last year, a friend gave me some young "Bishops children" that she'd raised from seed. They put on a good show and I cut them down in late Autumn 2011. After a cold Winter, covered in snow, they returned this year for their Summer holidays and are putting on an equally pleasing display now!
I think that maybe, if strong plants, all dahlias will develop tubers - but I maybe wrong. Hopefully, a dahlia expert will chip in with some answers,
Jenny namaste

 

You may find small tubers under the ground when you dig them up, after the frost has blackened them gently go round with a garden fork and if there is tubers lift them, put in shed to dry,clean the soil off, then wrap in newspapers to keep free from frost , then if they get through winter ok you can start them off in pots in spring.

Or you can do what most of us do, cover them with mulch and let them take their chance ,if they have tubers and survive whatever sort of winter we have ,they will come again next year.

 

As far as I know all Dahlias produce tubers after their first year from seed.
You can obviously grow them on in subsequent years if you want to.

Years ago I grew all kinds from seed, from the small collarette types to the giant ones with massive blooms.

The reason people buy tubers is because you then know exactly what you will get, flower wise, named varieties will be true to type.

With seed its a bit more uncertain and sometimes you get variation, which is basically how new named varieties are produced.

 

Yes, you can cross parent-A with parent-B to then sow the seed and try to get a "cross" with an interesting colour etc.

As Pete said you will know what you are going to get. I have grown Dahlias from seed and 80% of them were not worth keeping for a second year (well, nor for the first year either!)

Only reason to lift Dahlias, in my opinion, is:

• You want to make sure that they don't die in a cold winter (so these are just your "reserves")
• You want to propagate more of that variety, by "forcing" the tubers in the Spring you then get lots of shoots suitable for cuttings
• You want early flowers - tubers started off under glass in the Spring will flower earlier than those left in the ground.

 

Thanks everyone, very useful. Obviously, as is so often the case with this garden lark, the secret is to wait and see!