Most important, be extremely careful when pureeing hot soup. If time allows, it is safest to cool the soup before pureeing it. If you're in a hurry, at least cool it to not much more than body temperature. To reduce the chance of spattering, pulse the blender on and off a couple of times before leaving it on, then hold the top down until you're sure it's not going anywhere. Although the arrival of spring and fresh local vegetables may prompt you to consider soup, the recipes on Page 4C are just as good with frozen vegetables.
Cooks happily use frozen peas, given the labor saved.
Frozen spinach tastes nearly as good as fresh, although it doesn't save much time or effort. But frozen asparagus is simply not as flavorful. Reduce heat to a simmer, and cook until peas and ginger are very tender, about 15 minutes. Cool at least a few minutes. Pour soup into a blender, in batches if necessary, and carefully puree.