As you scan seed catalogs and plan your vegetable garden, remember to rotate crops to limit pest and disease problems. In designing the garden, remember, too, that some vegetables use more nutrients than others. The greatest feeders are tomatoes, peppers, eggplants, potatoes, and cole crops. Rotate these crops with nitrogen-fixers, such as peas and beans, or cover crops like clover or alfalfa. Gather Seed-Starting SuppliesGo over seed-starting supplies on hand and determine what you need. If reusing trays or pots, scrub them well. Purchase a soilless mix specifically designed for seed starting. Plastic domes are helpful in supplying humidity, while specially designed heat mats help speed germination. Consider a fluorescent light unit if starting seeds indoors rather than in a greenhouse. Experiment with some of the newer types of seed-starting equipment, too. Grapes need to be pruned every year during winter to ensure fruiting. Once a cane has fruited, it won't fruit again. Fruits are formed on new growth that arises from the previous season's growth. For American grapes, such as 'Concord', the four-arm Kniffen System is usually used. For established plantings, maintain four, well-spaced arms, trimmed back to ten buds. Choose four more canes for renewal spurs and cut these back to two buds. Force Flowering Shrub BranchesForsythia and pussy willow are the easiest of the spring-flowering shrubs to force into bloom for bouquets, but try others as the season progresses. Select branches with numerous large, plump buds. Split the cut ends and place in a container of warm water set in a dimly lit, cool location. Mist several times a day and change water daily. Buds should open in one to two weeks. Move to a bright room when flowers begin to open. Test Leftover SeedAs you plan and order seeds for this year's garden, test leftover seed for germination. Place ten seeds between moist paper toweling or cover with a thin layer of soil. Keep seeds warm and moist. If less than six seeds germinate, then fresh seed should be purchased. If you only have a few seeds, then reduce the test size.