If you are buying bare-root trees, look for ones with large root systems in relation to top growth. It is not necessary to purchase a very large tree to get a quality plant.
Dig, divide, and replant crowded summer and fall flowering perennials like Agapanthus, Garden Phlox, Astilbe, Aster, Bleeding Heart, Coral Bells, Daylilies, and Shasta Daisies. Perennials perform best in well-drained soil with plenty of humus. Astilbe, Hosta, and Bleeding Heart bloom in the shade.
Plant spring-flowering annuals such as Forget-me-nots, Dianthus, Englich Daisy, Sweet William, and Viola.
Wait until the end of the month to set out frost tender plants.
Repot house plants that have grown too large for their containers. Cut back leggy plants to encourage compact growth. Root cuttings in moist media to increase your supply of plants.
Bluebells are good for naturalizing in the same manner as Daffodils but prefer a shadier location and will bloom even where they get no direct sun.
Accurate information on the longevity of flower seeds is hard to find. Based on limited observations, the following should be considered as short-life (one year) seeds: Aster, Candytuft, Columbine, Ornamental Onion, Phlox, Salvia, Strawflower, and Vinca. Some common flower seeds viable for more than one year if stored properly are Alyssum, Calendula, Centaurea, Coreopsis, Cosmos, Marigold, Nasturtium, Petunia, Salpiglosis, Scabiosa, Schizanthus, Sweet Pea, Verbena, Viola and Zinnia.
Fertilize plants that are starting to grow actively like annual flowers, berries, citrus, roses and established trees and shrubs with a balanced fertilizer like 15-15-15 or a 5-5-5.
Early spring is the right time for two special turf treatments, if needed: vertical cutting or thinning to remove thatch and aeration or coring to reduce soil compaction.
Wait until later in the month to fertilize lawns.