Start Cold Crops Inside
If you haven’t done so already, early March is a good time to start seeds of cold crops such as lettuce, cabbage, broccoli, Brussels sprouts, and cauliflower indoors under lights. By April, you’ll have plants that are ready to be transplanted outside a few weeks before the last frost date.
Get a Head Start on Herbs
Begin planning your herb garden and start seeds of basil, parsley, sage and thyme indoors. Start your herbs in flats filled with moistened seed-starting mix. After germination, place the plants under grow lights or by a sunny window and be sure to keep the soil moist.
Remember to Rotate
When planning your spring and summer vegetable garden, remember to avoid planting crops in the same family in the same spot more than once every three years. Tomatoes, peppers, and eggplant are in the same family; so are squash, cucumbers, and pumpkins. Many pests and diseases overwinter in the soil, so moving plants around can disrupt their life cycles and minimize the need for pest and disease controls.
Prune Trees and Shrubs
March is an ideal time to prune most trees and shrubs. Spring-flowering shrubs, such as forsythia, lilacs, and azaleas, should be pruned immediately after flowering, but you can remove dead or damaged branches any time.
Cut branches of early-flowering shrubs such as forsythia, quince, and pussy willow to force into early bloom. After cutting, bring the branches indoors and place them in a vase of water. After a few weeks, they should bloom. Once pussy willows reach their peak, remove them from the water and allow them to dry; they’ll continue to look great in dried arrangements.
Get an early start on planting begonia tubers in containers this March. Plant them hollow-side-up in well-drained potting soil. Set them in a warm (70 degrees F) location and keep the soil moist but not too soggy. After you see growth in about 3 or 4 weeks, move the containers to spot with bright, indirect light. Once all danger of frost has passed, you can transplant the begonias outdoors.
Early Sow Flowers
Although April is the month to sow seeds of many flowers, some take longer to mature and so should be sown this month. Flowers you may sow early in March include dusty miller, geranium, heliotrope, impatiens, osteospermum, petunia, mealycup sage, torenia, verbena, and annual vinca. Flowers you may sow the middle to end of March include ageratum, coleus, dianthus, ornamental millet, African marigold, ornamental pepper, annual phlox, rudbeckia, scarlet sage, and thunbergia.