First your horseradish root will be fine - the biggest complaint about this herb is that it spreads to enthusiastically by underground roots. Second, you can start planting peas and other cool season crops in late February or early March when you see the daffodils in bloom. If you are wondering when you can plant fruit trees and roses you can plant bare root plants like this as soon as you see them for sale at the nursery. Just don't dig when the ground is frozen. That being said, I don't' see the advantage of planting so early. If wait until April to plant the soil will have dried out a bit and your seeds will be less likely to rot. In the wet climate of Western Washington growing vegetables in a raised bed is the way to go especially if you want to get started in early spring. A good book to get you started is \"Growing Vegetables West of the Cascades\" by Steve Solomon. Keep growing, Marianne Binetti