Well, ted, that would all depend upon where you live! Although Arabian Night could normally be bought here, I don't recall seeing Bristol Stripe or Tahiti Sunrise here. And I know I haven't seen Myrtle's Folly, because I would snatch it up in a second. Now that I pretty much know which of my tubers did or didn't survive, I checked our local grower's website...he's all sold out...of everything. And I've been looking at the local stores and there hasn't been much of anything this year, except mixed packages of unnamed tubers. If I had decent looking tubers that I hadn't planted yet, I'd trade.

Coincidentally, my grocery store also had their display up today, and today was my monthly shopping trip (COVID has changed the way I do things a lot). I walked out with five new dahlia. I'll find homes. The freesia and ranunculus I picked up...there's always a home for everything. Somewhere. I start my old dahlia and new in pots every year, about four weeks before the "absolute guarantee end of frost" to give them a head start. It works great. With so little time in pots, I just give them whatever's on-hand and whatever soil I have left-over by that time. Average last frost for me is April 20th, but I won't plant the dahlia until May 1st at the earliest in the most protected parts of the beds, and May 10th in most of the rest for warmer soil. As noted, just lop off anything broken or nasty looking. Damp the soil, you don't need to soak it. And be patient. Some are morning-birds and shoot out in days. Some will take a while. Taller dahlia do benefit from being staked or, if you're lazy like I am, being planted in tomato cages. Shorter ones don't care. Not recommended but if you have to...: Don't push it too far and keep an eye on the soil and air temperatures. https://www.greencastonline.com/tools/soil-temperature You can cheat a little bit by using a sunny southern bed with a dahlia--the "formal" soil temp may not be quite sixty, but the temperature there will be, and an already-sprouted dahlia won't stop growing just because it's a little chilly (these are my "May 1" planted dahlia). Been there, done that, got the T-shirt. They'll slow, stall, and wait, but they won't die unless temperatures fall to frost. Consequently, my mailbox dahlia tends to be a bit late and slow, but since it was already 2' tall when I planted it, OK (my May 10 dahlia--soil's still a little cool, but not too far off by then).

agree with them.. but 2 further thoughts ... if you buy potted plants ... now might not be the best time to be planting... you would probably be better off 'holding them over' until a better planting time in fall ... also ... the plant culture variables are key ... and 'plenty hot and sunny' .. is but 2 of them ... when perfecting this.. you need to take them all into account .. e.g. a plant needs a fully established root mass to pump enough water to offset high heat ... you cant... or shouldnt transplant in heat .. disturb the roots ability to pump water ... and then hope the plant shows no stress ... ergo.. you plant when it cools off ... now is a great time to be thinking about this.. and planning.. but not really the time for action ... ken

For OP or anyone who ckmes across this: the only way to know for sure if the tuber is done (apart from being so dry there is zero gove to the tubers at all, they are thoroighly crispy, soft rotten or spongy) os to get them going. i have thigubt many were goners thst, once planted up, speouted eyes. It seems to me that there is more hope if you have a bit of a clump than if the tuber has been divided to its tiniest possibly viable parts.