When tulips, daffodils and lilies burst into bloom, you’re probably not thinking much about the part of the plant that’s underground: the bulb. Flower bulbs are actually a type of food storage organ, a way that plants stash their homemade nosh to help fuel future growth and flowers. Many plants get lumped under the heading bulbs, including tubers, corms and rhizomes. Knowing a little about different types of bulbs can help you understand how these plants grow—and how you should handle them at planting time.
Lily bulbs lack an outer protective, papery layer. They’re often sold packed in sawdust or peat moss. It’s important to store lily bulbs correctly prior to planting because they have no outer layer that helps protect against moisture loss or temperature fluctuations. Keep lily bulbs cool (below 45 degrees F) but not freezing to help prevent sprouting. If sprouts form prior to planting, handle bulbs carefully. If you break the sprout, the lily won’t flower that year.
A garden of yellow tulips and daffodils blossom in this cottage style garden. Planting bulbs separately from other blooming shrubs allows the tulips and daffodils' beautiful blooms to be the focus and so they don't compete with other flowers.
Most cooks value fresh garlic, and many a gardener also enjoys its large spring Allium flowers. The ones that grow best locally are often shared between gardeners, who plant individual cloves in the fall and harvest and dry the bulbs the following spring.
The canna is a popular tropical plant that’s not hardy where the soil freezes solid. It grows from a type of bulb known as a rhizome, which is located at or just beneath the soil surface. A rhizome is basically an enlarged or fat stem that stores starches and other easy-to-use plant foods.
Fall is the time to plant flowering bulbs, such as daffodils and tulips, as well as perennials, trees and shrubs, according to the National Association of Landscape Professionals. The warm soil is great for root development, and plants have several months to establish themselves before the stress of the summer heat.
Once known as false forget-me-nots, brunnera are shade-loving plants with blue flowers like this variety, 'Henry's Eyes'. These perennials open in early spring and make great companions for hostas, pink and white bleeding hearts, early tulips and other spring-flowering bulbs. Grow your plants in fertile, moist soil, and don't let them dry out.
Colorblends' Tulip Blend Rainbow Coalition presents one of those color displays that only tulips can pull off. Orange opens first, then red joins in, and purple closes ranks. In the end, the three bloom together for as long as a fortnight. Colorblends is a Connecticut-based flower bulb wholesaler that sells direct to landscape professionals and home gardeners coast-to-coast. See Colorblends.com or call 1-888-847-8637.
Narcissus refers to a genus that includes daffodils, paperwhites, jonquils and other bulbs—but most of us think of the big, trumpet-shaped flowers as daffodils and the small, white ones as narcissus. (When they’re grown around the holidays, narcissus are often called paperwhites.) 'Golden Harvest,' shown here, is a vigorous, early-flowering bulb that dates back almost 100 years. Like other bulbs in this genus, narcissus should be planted in autumn.
Inside a true bulb is a central shoot that contains layers of leaves and immature flowers. With bulbs planted in your garden, this central shoot forms after flowers fade. This is why it’s important to let leaves of bulbs like tulips and daffodils remain and stay green until they naturally die back. As long as leaves are green, they’re helping to store food that helps form the shoot for next year’s show. Most true bulbs have a protective papery skin (think onion, daffodil, tulip). An exception to this rule are the lilies, including Asiatic and Oriental types.
For best results, plant tulip bulbs, pointed ends up, about 6-8 weeks before the first hard frost in your area. Larger bulbs should be planted deeper (usually 8-10” deep) than smaller ones (usually 5-6” deep). Because tulips need a certain amount of cold weather to flower, they may not come back after the first year or two. If you live in a mild climate, ask your local county extension service agent if you should buy pre-chilled tulip bulbs, or chill them yourself, in your refrigerator, before you plant.
“Remember me” is the message of gladiolus, birth flowers for August. The flowers can also mean strength and integrity, while the sword-shaped leaves suggest love-pierced hearts. In ancient times, glads were associated with magical powers.
Fall-planted Dutch iris are easy to grow and make lovely cut flowers. Get the bulbs into the ground before the first hard freeze and give them a site with full sun to partial shade. They should be planted about 4-6” deep and 3” apart. Let the leaves remain on the plants until they die back naturally, and the bulbs, which are hardy in zones 5-9, should flower again the following year.
Plant crocus bulbs just underneath your grass in fall for early spring color. 'Hokus Crocus,' shown here, is a mix of purple, white and purple-white striped varieties. These dainty flowers like a sunny garden spot and typically multiply as time goes by. Wait six to eight weeks before you mow over their foliage so you'll have repeat blooms next year. (The small bulbs usually flower before the grass needs mowing anyway, and the thin, narrow leaves blend in with your lawn.)