I have 50 dahlia tubers to plant and a similar number of gladiola corms. Spring, up until very recently, has been cold, wet and windy. When will the ground be warm enough to plant these flowers? I don't want them to just sit and rot, but don't want to miss the earliest opportunity to get them into the ground. Also, I have six "own root" roses I planted last summer. There is very little green on them right now, and the rest of the stems are black. I know they are supposed to grow back from their own roots. Do I prune back all the black canes now, and wait and see what happens?