Glorious sweeps of daffodils delight visitors every spring at The Morton Arboretum. These flowers were chosen because they make especially good companions for trees, such as the magnificent oaks in Daffodil Glade.

In addition to being hardy, tough, and unattractive to animals, daffodils (Narcissus) live a long time, according to Julie Janoski, manager of the Plant Clinic. That’s important when you’re planting beneath a tree.

“Digging damages tree roots,” Janoski said. “But with long-lived bulbs, you’ll only dig once.” The tree’s roots will have time to heal and then it can easily co-exist with the bulb plants. These bulbs are a much better way to get spring color under trees than annual flowers such as pansies or short-lived bulbs such as hybrid tulips, which require you to dig every year. Other longlived spring-flowering bulbs include Siberian squill (Scilla siberica) and snowdrops (Galanthus nivalis).

Not all bulbs can thrive beneath a tree. “It’s essential to choose species and varieties that are shade-tolerant or bloom early in the spring, before the tree opens its leaves,” Janoski said. Bulbs need sunlight to flower. As long as a tree’s branches are bare, light can reach the plants below. Once the tree spreads its leaves, there’s too much shade for most bulbs to bloom. Plant later-blooming daffodil varieties or other bulbs such as tulips and alliums out in the open away from trees, where they can get sunlight in late April or May.

Daffodils bloom for weeks at the Arboretum each spring. How is that possible? The trick is to plant a mix of varieties that have been selected to bloom at different times, says Janoski. “Each variety may only bloom for a few days, but if you combine several, the show will go on.” Exactly when the flowers open will depend on the weather, which varies every spring. But the sequence won’t change. Like other spring-blooming bulb species, daffodils are planted in the fall. Spring is the time to admire their blooms and decide which varieties to plant this autumn to flower next year.

Here’s a sample of the dozens of daffodil varieties that brighten the springtime at The Morton Arboretum.

Narcissus ‘February Gold.’ This petite plant with small yellow flowers blooms very early (although probably not February in the Chicago area) and works well under trees.

Narcissus ‘Ice Follies.’ Blooming in early to mid-spring, Ice Follies has white-and-yellow flowers.

Narcissus ‘Mount Hood.’ All-white Mount Hood blooms in mid-spring. Since trees are beginning to open their leaves by that time, it’s safest to plant daffodils that bloom in mid-spring or later well away from trees, where they can get full sun.

Narcissus ‘Tahiti.’ With a fluffy cluster of yellow petals tinged with red-orange, Tahiti blooms in mid- to late spring.

Narcissus ‘Delnashaugh.’ This late spring bloomer has flowers that combine white with pale pink.