Spring planting is important in the garden's yearly cycle. As the soil begins to warm up, seeds can be planted, or they can be started earlier indoors. Flower and vegetable seeds can be started indoors in small plastic containers or egg cartons. Spring planting is also the best time to put in bare-root plants such as perennials, roses and berries. Soil is ready to work when it is dry and a shovel slides easily into it.
The first day of spring is March 20 in the United States, but the weather can still be too cold to plant in the garden. Spring arrives at different times in different climates. The USDA Hardiness zone map gives average temperatures for local climates. Spring growth starts when the soil warms up enough to germinate seeds. Many seeds germinate at 60-75 degrees F. Gardeners often start vegetables and tender annuals indoors in February and March to plant them in the garden when the weather warms.
Spring is traditionally the time to put in a vegetable garden and start annual flowers by seed. Spring gardening can be started by cleaning up the flower beds and vegetable area to prepare for planting. Winter's debris should be raked and put on the compost pile. Soil may still be cold, hard and difficult to work with a shovel. In warmer climates spring is a time to incorporate more compost into the soil in preparation for planting time.
Sweet alyssum, phlox, zinnias and marigolds are flowers to start indoors in February and March. Brussels sprouts, cabbage, cauliflower and lettuce are vegetables that can be started by seed in early spring. In warmer climates, these vegetables can be set directly into the ground. When soil temperature reaches 65 degrees F, Swiss chard, parsnips, peas, asparagus, beets and corn can be planted. Tomatoes, cucumbers, and snap beans begin their germination process at 60 degrees F.
Spring planting times can range from February to late May. Local conditions may vary greatly. Planting seeds too early can lead to seed rot, slow germination, poor growth and disease. Use a soil thermometer for three consecutive mornings to check your soil temperature, suggests Texas A&M University. Seeds started indoors are ready to transfer to the outdoor garden by May, even in cold zones. Gardeners in northern climate zones traditionally consider Memorial Day the beginning of the growing season.
Spring Bulbs and Bare-root Plants
Bulb flowers that are planted in the spring include dahlias, lilies, cannas and alliums. As the sun warms up, the soil can be worked with a shovel. Compost added to the soil before bulbs are planted ensures healthy growth. Spring is also the time to plant small bare-root fruits such as blackberries and raspberries. Bare-root roses are purchased in early spring and planted as soon as the soil can be well worked.