Picture your neighborhood in April, when your heart is lifted by bright blue squill, white snowdrops and yellow daffodils. Aren’t there spots in your yard just begging for that bloom?
“If you want to maximize that feeling of springtime, fill those spots with spring-blooming bulbs now,” said Spencer Campbell, Plant Clinic manager of The Morton Arboretum in Lisle. “Fall is the time to plant them.”
Fitting in more spring bulbs will do more than brighten your yard. It also will provide nectar and pollen early in the season for bees and other pollinators.
Each brown bulb you plant in autumn contains a dormant plant. Once the bulb was fully developed, it was dug up and stored dry. When you plant it in still-warm autumn soil, the bulb will grow roots. Then it will wait through the winter until warming soil signals the dormant plant inside to sprout and bloom.
“Planting bulbs in early fall gives them plenty of time to grow the roots they need,” Campbell said. It also ensures they have time to chill. Spring-blooming bulbs won’t bloom unless they spend enough time in cold soil; most species need their bulbs chilled below 40 degrees for 12 to 14 weeks before they sprout.
This fall, look around for places where you could fit in a little more spring bulb cheerfulness. For example, tuck snowdrops and squill, which can handle a bit of shade, around the base of shrubs, where they will bloom in early spring while the shrubs’ branches are still bare.
You can also use those somewhat shade-tolerant bulbs, along with early-blooming varieties of daffodils, beneath deciduous trees. They’ll bloom in the early spring sunshine before the tree opens its leaves to shade them. “When you plant, be careful not to damage tree roots,” Campbell said. Choose bulbs that are small in size for a site under a tree so the holes you dig can also be small.
Consider scattering bulbs of early crocuses such as Crocus tommasinianus around in a lawn. “If you delay mowing the lawn until May — which is good for the grass anyway — you’ll give the flowers time to finish blooming,” he said. Then their fine, narrow leaves will all but disappear among the grass blades.
Tulips, daffodils, alliums and bluebells can be planted among perennials as long as the bulbs you choose are compatible with the other plants. Most kinds of bulbs need full sun and well-drained soil.
You can even plant bulbs in containers, if you have a sheltered but unheated place to store the planted pots over the winter. “Don’t bring them indoors, or they won’t get the chilling they need,” Campbell said.
Planting bulbs is easy. Start by digging a deep hole, two to three times as deep as the bulb is tall. A deep hole protects the bulb against fluctuations in the weather.
Place the root end down. On tulips and daffodils, that’s the wide, flat end; the pointy part, where the stem will grow, goes up. On other bulbs, the root end may be harder to discern. Look for little dots where the roots were attached. “If you really can’t tell, plant the bulb on its side,” Campbell said. “The sprout will find its way.”
There’s no need to fertilize bulbs when you plant them. They have a food supply built-in. Good soil that is rich in organic matter will supply all the further nutrients they need.
After you plant the bulbs, water them thoroughly and spread a 1- to 2-inch layer of mulch on the soil that covers them. That mulch layer will insulate the bulbs against their biggest danger: coming out of dormancy too early and sprouting during brief winter warm spells.
Then snuggle in and wait. “When winter’s over, the bulbs you plant now will greet you in springtime,” Campbell said.
For tree and plant advice, contact the Plant Clinic at The Morton Arboretum (630-719-2424, mortonarb.org/plant-clinic, or plantclinic@mortonarb.org). Beth Botts is a staff writer at the Arboretum.