CORVALLIS, Ore. — When it comes to plants, bulbs are among the easiest to grow — and fall is the time to get them in the ground.
Bulbs are naturally drought tolerant because they go dormant in summer and require no watering.
“You plant spring-flowering bulbs in fall, they grow over winter, flourish in spring and go dormant in summer,” said Heather Stoven, horticulturist with the Oregon State University Extension Service. “Once they’re in the ground, they do quite well over multiple years with little maintenance.”
Bulbs are naturally drought tolerant because they go dormant in summer and require no watering. If you’re planting bulbs among perennials or near shrubs, Stoven recommends pairing them with plants that also need little irrigation. If the area gets regular water, make sure the soil drains well.
Bulbs such as daffodils, tulips, crocus and hyacinths are planted in fall because they need time to establish roots before producing spring flowers. In most of Western Oregon, October and November are ideal planting months, though bulbs can be planted as late as mid-December if the soil is still workable.
In colder climates such as Central and Eastern Oregon, bulbs should be planted earlier — from late September through October — to allow two to three weeks for root growth before the ground freezes.
For detailed regional information, visit OSU Extension’s Gardening in Central Oregon's Climate and Tips for growing spring-flowering bulbs in Central Oregon.
Choosing and storing bulbs
When buying bulbs, choose large, firm ones — the bigger the bulb, the bigger the bloom. Avoid any with mold or soft spots. Plant bulbs as soon as possible after purchase. If you must delay, store them in a cool, dark place such as an unlit garage.
In Central and Southern Oregon, where winter storage conditions are often dry, check periodically to ensure bulbs do not desiccate before planting.
Planning your display
Before heading to the garden center, decide on color combinations and bloom times. Selecting early-, mid- and late-blooming varieties will extend your display. You might plant a bold sweep of a single color or mix different bulb types for variety.
For a natural look, dig larger holes for multiple bulbs rather than planting one at a time. “Groupings are really nice,” Stoven said. “You’ll get a mass of color.”
In Southern Oregon, mild winters and early springs make it possible to combine bulbs with warm-season perennials for a longer sequence of blooms. In Western Oregon, pair bulbs with ferns or hostas in partly shaded gardens to extend seasonal interest.
Planting tips
Follow the depth instructions on the package, but as a general rule, plant bulbs at a depth about three times their width. Add organic material such as compost, well-rotted manure or mulch to the bottom of the hole. Place the bulb pointed side up and cover with soil.
Bulbs prefer full sun and well-drained soil. Avoid planting in areas where water pools during winter. In Western Oregon’s wet climate, raised beds or berms improve drainage and reduce rot risk.
In Central Oregon, where winter freezes are common, amend the soil with one-third to one-half organic matter, add superphosphate or bulb fertilizer to the planting area, and water well after planting. Once the ground is frozen, apply about 3 inches of mulch — such as straw, bark chips or pine needles — to prevent freeze–thaw damage.
Fertilizer is not strictly necessary, but if you choose to use it, select superphosphate or a low-concentration fertilizer labeled for bulbs. Apply at planting time since phosphorus doesn’t move readily through soil.
There’s no need to dig bulbs after flowering. However, allow the foliage to turn brown and die back naturally so nutrients return to the bulb for next year’s blooms.
Central Oregon planting guide
Central Oregon gardeners face unique challenges due to cold winters and short growing seasons. To prevent frost damage:
- Plant in well-drained soil and full sun.
- Avoid south-facing foundations that warm soil too early and trigger premature growth.
- Water after planting and mulch once the soil freezes.
When flowers fade, cut them off to prevent seed production, which diverts energy from the bulbs. Allow leaves to die back naturally, as they store energy for the following season.
Heather Stoven’s picks for uncommon spring-blooming bulbs
Fawn lily (Erythronium oregonum)
An Oregon native wildflower with nodding white or yellowish flowers and mottled leaves. Prefers shade and thrives in woodland gardens.
Grecian windflower (Anemone blanda)
Delicate, star-like flowers in blue, white or pink appear above ferny foliage, which dies back soon after bloom. Works well in mass plantings. “Blue is especially nice to have as a contrast to yellow daffodils,” Stoven said.
Allium
A deer-resistant member of the garlic family that produces globe-shaped flower heads in purple, pink, blue or occasionally white. Sizes range from large blooms like ‘Globemaster’ to small drumstick alliums.
Fritillaria
This diverse genus includes the crown imperial (Fritillaria imperialis), with orange or yellow bell-shaped flowers on stems up to 5 feet tall, and the smaller native checker lily (F. affinis), which has purple flowers spotted with yellow.
Species tulips
Shorter, hardier and longer lasting than common hybrid tulips. They come in many colors, often with flowers that open wide in sun. Species tulips can self-seed and naturalize, providing years of blooms.
