How long has it been since they were dug out of the ground? Are they entire clumps or divided tubers?

The answer depends on the situation. Pictures would be helpful, too.

soak them for an hour and put them in flats barely covered with soil. if they are viable growing points should be swelling in a few days. plants are surprising and what have you got to lose. don't water the tubers after the initial soaking-dahlias are prey to just about every kind of fungus and rot you can think of.

Thanks to both of you for the responses. They have been out of the ground a while. But I thought I'd try. I was wondering if soaking be a good idea --I do that with other things. But I didn't want to do and find out that was the worst way to proceed. So I'm in NJ, should I do it now or wait until March or so?

the tubers will need warmth so waiting a few weeks is fine.

Again, I would treat them differently depending on if they are divided in individual tubers or stored as whole clumps.

I'm not a big fan of drowning them for an hour, though some growers do that. Either they already have enough moisture retained in the tubers to keep the meristem tissue responsible for new growth alive, or it's shriveled past life. Soaking might deteriate its last defenses, leaving it open to fungal and mold attacks.

If you have whole or half clumps, I would put one in a pot and lightly moisten the soil, leaving it at room temperature. The soil would moisten it while protecting from spores.

If you have individual tubers (like chicken legs), I would take a couple and put each in a sealed ziplock bag with a squeezed out moist cotton ball. You can monitor it closely for sprouts or roots, and get a good idea if the rest are worth saving.

Either method, done now with only one or two, will give you a good idea if you should be seeking new dahlia tubers from another source for this coming season.

Hope this different perspective helps.

Cheers!

I'll take a pic to post in the next couple weeks. decided that no hurry in doing anything since they have been dormant for a long time. Thanks again for the info.