Illustration by Em Roberts
Soon after its spring bloom is finished, a bulb lies dormant for the summer. Winter is when the work begins. When temperatures drop below 40 degrees, the chill triggers tender new roots to form, supporting the tiny flower that is taking shape in the heart of the bulb. When spring arrives, the fully formed flower will break ground and bloom. It will fade in a few weeks, but its foliage lives on, gathering food reserves in late spring before dying back itself. Below ground, a new slender shoot wrapped in fleshy layers of storage tissue begins to grow. It will spend another summer in dormancy before the sequence begins again.
In Richmond, bulbs are best planted in November, in time for the critical 14-week chilling period. Select a site with well-drained soil that gets six to eight hours of direct sunlight each day. Plant them root-end down, point up, in a hole that is twice as deep as the bulb is wide.
For continuous waves of color from early to late spring, plant a variety of bulbs that will flower in succession, horticulturist Dean Dietrich suggests. Dietrich, a horticulture section leader at Lewis Ginter Botanical Garden, has been designing the spring bulb display in the Central Garden for seven years. “Snowdrops are one of the first to bloom, followed by crocus, daffodils, tulips, hyacinth and then wild hyacinth,” he says. Plant them alongside violas, columbines and forget-me-nots, which bloom at the same time. “Make the color last by interplanting with foxglove, Virginia bluebells and calla lilies. After spring-flowering bulbs are finished, fill in the spaces with tender bulbs like dahlias, gladiolas, canna lilies, caladium and summer annuals.”
Plant in Clusters
Early spring bulbs like purple woodland crocus, winter Hellebore or white snowdrops are critical food sources for insects. They break into bloom just as young pollinators hatch, before other nectar sources are available. Plant them in clusters to create a concentrated food source.
Planting in clusters also creates visual impact — arrange large bulbs in groups of odd numbers, small bulbs in naturalized drifts. Dietrich plants larger bulbs such as tulips and daffodils 6 inches on center, with shorter plants in front of taller varieties. Or, “plant in layers, smaller bulbs over larger ones,” he suggests, “for an uninterrupted show of color.” He frowns on the practice of tying or braiding daffodil foliage at the end of the bloom cycle. “It reduces sun exposure during a time when the plant needs exposure the most,” he explains. Instead, deadhead the flowers and leave the foliage intact. “Let it sprawl and collect as much sunlight as possible.” Layer perennials like hosta over the daffodil foliage to distract the eye.
Dietrich recommends treating tulips like annuals in Central Virginia. “Daffodils and other bulbs will rebloom here year after year, but tulips prefer light, sandy soil to our heavy clay.” He fertilizes bulbs with blood meal or bone meal after they bloom. “There is no need to fertilize daffodils. They stored all the energy they need last year,” he explains.
