The Ws (plus an H) of Bulbs
The great thing about planting bulbs is that they will bloom year after year. Here's what you need to know to grow bulbs successfully in your garden and look forward to early spring color.
Marjorie Blare, Master Gardener
Who should plant bulbs?
Why plant bulbs?
Bulbs can provide color all in all three seasons and many bulbs will return year after year. Most bulbs prefer full sun but some bulbs even thrive in shade!
What are bulbs and what kinds to plant?
What we loosely call bulbs are actually a group containing: true bulbs (Tulips, lilies), corms (Crocus), rhizomes (Callas, Iris) and tuberous roots (Dahlias, Tuberous begonias). All of these plants have a self-contained food storage system that has adapted to living underground. Bulbs are either hardy (perennial) or tender (need to be dug and stored) and this will determine where you plant them. Most people are familiar with Tulips, Daffodils and Lilies. All of these come in early, mid-and late season, as well as short medium and tall. There are a host of small bulbs that are often overlooked. Many of these will grow well in areas under trees because they flower before the tree leaves out.
Where should I plant bulbs?
Most bulbs should be planted in full sun. They don't like wet feet. Most bulbs will do well in soils ranging from sandy to clay. Jack-in-the-Pulpits, Trillium, Tuberous begonias and Martagon lilies are bulbs that will grow in the shade.
How do I plant bulbs?
Dig a hole two to three times deeper than the bulb's circumference. Amend the soil with organic matter. You may have heard of putting bone meal in the hole, don't do this unless you have a soil test (https://soiltest.cfans.umn.edu/) that shows your soil needs calcium and phosphorous. According to the University of Colorado, bone meal will only be available to plants in soil that has a pH level of 7 or lower. Dakota County soils tend to be naturally high in phosphorous. Make sure to plant bulbs deeper if your soil is sandy. Putting a wire barrier over the bulbs may deter digging critters. It is recommended to plant odd numbers of bulbs for aesthetics. Smaller bulbs can be planted on top of larger bulbs, rather like a fruit cake.
When do I plant bulbs?
Bulbs can be planted from late September through late October in Minnesota. If you are dividing bulbs, wait for the foliage to dry, but you can move them immediately. Some bulbs, such as lilies, can be moved “in the green”, as long as they are done blooming, and are taken care of through any dry, hot weather. If you wish to overwinter tender bulbs, plant them where it will be easy to dig them in the fall.
For more information go to https://extension.umn.edu/how/planting-bulbs-tubers-and-rhizomes
For information on growing bulbs indoors go to https://extension.umn.edu/planting-and-growing-guides/growing-bulbs-indoors.
Photo credits: Carolyn Plank (1), Deborah Snow (2), University of Minnesota Extension (3)