- About Extension
- Get Involved
- Statewide Locations
Go underground with bulbs for colorful spring bloom
September 11, 2015
CORVALLIS – When it comes to plants, bulbs are about as easy as it gets.
“You plant them in fall, they grow over winter, flourish in spring and go dormant in summer,” said Heather Stoven, a horticulturist with Oregon State University’s Extension Service. “Once they’re in the ground, they do quite well over multiple years with little maintenance.”
On top of that, bulbs are drought-tolerant. “That’s one of the great things about them,” she said. “Since they go dormant in summer, they don’t need to be watered.”
If you plan to intermingle bulbs with perennials or place them near shrubs, pair with plants that don’t need much irrigation, Stoven said. Or, if the area does get regular water, make sure the soil drains well.
Bulbs such as daffodils, tulips, crocus and hyacinth are planted in fall because they need some time to get their roots going before pushing up to put on a spring show. Although October and November are ideal for planting, bulbs can go into the ground until mid-December.
When shelling out money for bulbs, make sure you choose large ones. The bigger the bulb, the bigger the bloom, Stoven said. Also, avoid those with mold or soft spots, which signal rot. Plant as soon as possible, but if something comes up to delay you, store bulbs in a cool, dim place such as an unlit garage.
Before heading to the garden center, make a plan. Decide on color combinations. Do a little research so that you can choose early, mid- and late-blooming varieties for a longer display. Think about what to plant together – a mix of different types of bulbs is an attractive option.
As you get ready to plant, dig holes to fit multiple bulbs rather than planting one at a time. The effect is more natural.
“Groupings are really nice,” Stoven said. “You’ll get a mass of color.”
When digging the hole, it’s best to follow directions on the package for planting depth, but a general rule of thumb is three times as deep as the bulb is wide. Add some organic material – compost, well-rotted manure or mulch – to the bottom of the hole, place bulb pointed side up and cover with soil. Adding fertilizer is not necessary, but if you feel compelled, use super phosphate or a low-concentrated product labeled for bulbs, Stoven said.
There’s no need to dig bulbs up after flowering, but letting the foliage turn brown and die back is a good idea so that the nutrients contained in the leaves return to the bulb and it can start the cycle once again.
Here are Stoven’s recommendations for uncommon spring-blooming bulbs:
- Fawn lily (Erythronium oregonum) – An Oregon native wildflower with dainty, nodding white or yellowish flowers and brown-stained leaves. Doesn’t mind shade and looks inviting in a woodland setting.
- Grecian windflower (Anemone blanda) – Delicate, star-like flowers come in blue, white and pink on frilly foliage that melts away soon after bloom is over. Best used in a mass. “Blue is especially nice to have as a contrast to yellow daffodils,” Stoven said.
- Allium – Part of the garlic family, this deer-resistant bulb puts up a stem with one ball-shaped flower, usually in shades of purple, pink and blue, more infrequently white. Sizes vary widely from the 10-inch flowers of ‘Globemaster’ to the tiny pops of one-inch drumstick alliums.
- Fritillaria – Another group of bulbs with wide variation. On crown imperial fritillaria (F. imperialis), bell-shaped flowers in orange or yellow hang in clusters from single stems up to 5 feet tall. The much-smaller native checker lily (F. affinis) has dark purple flowers spotted irregularly with yellow.
- Species tulips – Just like their big siblings, but shorter, hardier and longer lasting. These bulbs will seed themselves so they’ll naturalize and give years of enjoyment. For more information on the group, check out a fact sheet from OSU Extension.
Source: Heather Stoven