Early Spring Bulbs

April

Winter AconiteThey twinkle beside sidewalks, peek up from the leaf litter or among groundcovers, carpet the ground with blue. While tulips and daffodils are still pushing up green sprouts, many small bulbs are already joyously in bloom.

Snowdrops are the early favorites. But in the Graham Bulb Garden and all through the islands, they are followed by crocus, scilla, chionodoxa, puschkinia, and grape hyacinths. Though many are early bloomers, small bulbs can span the season from March to May.

Little bulbs, with their light texture, can romp charmingly between masses of larger, showier bulbs. They can fill the space between just-sprouted perennials whose foliage will cover their faded foliage after bloom. They can create charming combinations, such as the classic blue scilla (or, later, muscari) and yellow daffodils.

Some can tolerate more shade than most bulbs, partly because they tend to bloom earlier before the trees leaf out. Many are relatively unpalatable to squirrels. In the right spot, they will live for many years.

Their basic requirements are just like a daffodil's: planting in fall, so they get a good winter's chill; sun; and fertile, well-drained soil. They need moisture to bloom, but they usually get it in a Chicago spring.

Since their leaves tend to be slender, grasslike and unobtrusive, most gardeners can stand to leave them alone after the bloom is done. That's a good thing, because any bulbous plant's leaves are the energy factory it depends on to make a flower for next year.

A moderate dose of balanced fertilizer after they bloom helps the plants with that flower formation.

In Chicago's erratic climate, the biggest danger to all bulbs is a treacherous thaw in mid- or late winter that tricks them into blooming too early. Not every winter provides the steady, insulating snow cover we enjoyed this year, so it's wise to mulch all bulbs to keep the soil temperature steady.

April brings the big show of large-flowered Crocus vernus and Crocus flavus, in tones of purple, white, and gold. Less spectacular species that often bloom in March include lavender-flowered Crocus tommasinianus (less tasty to squirrels than its larger cousins) and Crocus chrysanthus, which blooms butter-yellow, pale blue or white.

These delicate little treats don't make much of an impact one by one. Like most of the small bulbs, they are best planted in masses, in spots where you will walk by them on the sidewalk or can appreciate them from the window.

April also brings scilla, usually the banner-blue Scilla siberica. It's a tad more shade tolerant than many bulbs; you can tell how much shade it can stand by watching where it spreads by seed.

In the lawns of easygoing homeowners, scilla will sometimes spread into glorious carpets of blue. But planting scilla, or any small bulb, in the grass will be futile if you demand a tidy lawn and plan to start mowing just after the bulbs bloom in spring. Cutting off most of their leaves will starve them.

Grape hyacinths, which begin to bloom in mid-spring, do look like tiny hyacinths, in colors from pale blue to royal purple. The most common species in midwestern gardens are Muscari armeniacum and Muscari botryoides. In a sunny spot muscari often spread by seed.

The grasslike leaves of muscari emerge in fall, not in spring with the blooms, and often persist well into winter. That makes them less of a good companion for groundcovers than most small bulbs. But they do very well planted among daffodils or summer-blooming perennials.

By April, snowdrops have already done their job as the heralds of spring. They often do push their white bells up through snow in late January or early February. The most popular species is Galanthus nivalis, including a double-flowered cultivar, 'Flore Pleno.'

Snowdrops multiply by underground offsets into dense clumps of foliage that lasts long after the blooms. They do well at the base of deciduous shrubs, where they will be out of the way; they will bloom before the shrubs put out their leaves.

A starlet among the early bulbs is Glory-of-the-snow (Chionodoxa forbesii). In the center of each bright-blue flower is a dot of white that makes these blooms almost appear to twinkle.

Pale-blue Puschkinia scilloides is another early bloomer. So is winter aconite (Eranthis hyemalis), which is not actually a bulb, though it tends to be classified with them because it blooms so early. It has yellow buttercup-like flowers on low plants and happily reseeds in alkaline soils.

Adding these small, sturdy bulbs to the palette of bloom extends the flowering season and greatly expands the charm of the spring garden.