Is this really the time to be planting dogwoods?
Absolutely. The best time is while the plant is dormant; which is fall through about February. Dogwoods set their buds in October, November, though, so you'll be able to see how many blooms will pop out.
What kind should you buy?
We're recommending disease-resistant dogwoods, which are actually grafted, and should have one of the Bazillion Bloom tags at the local nursery.
What's most important when you plant?
Not to plant too deep. If it comes in a pot, you want the soil at the top of the pot to be level with the ground, not higher or lower.
How deep should you dig?
It's not so much the depth as the width—you want to break up the soil where the roots will grow out, digging almost a bowl shape. A rule of thumb is three times the width of the root ball, just deep enough for the root ball to be level with the soil.
What about fertilizer and water?
You don't need to amend the soil—it's better to have the plant get used to its new native soil. But water after you've put about half the dirt back into the hole, and again when it's full. I turn my shovel upside down and poke holes in the soil to burp it, too—air pockets can cause the roots to rot if water gets trapped there. Then the first two years the tree is in the ground, water it if it gets really dry.
Are the trees with half white/half pink or red blooms a bad idea?
No, they're just different blooms grafted onto the same root stock. It's a novelty, so you would have to ask for it or special-order it at a local nursery.
For more about planting dogwoods: utextension.utk.edu/publications/pbfiles/PB1670.pdf