Bulb Planting Times, Depths, Spacing
and Growing Requirements
Bulbs, Corms, Tubers and Rhizomes for your Garden
Growing bulb type flowers is a very rewarding task, considering the ease of planting and the resulting flower shows.
If you didn't get exact planting directions with your bulbs, there are a few general rules of thumb that you can usually rely on when it comes planting and growing bulbs.
- The pointy end always goes up! If you put the point down, your plant will still grow... but upside down. It will eventually get turned right side up and probably reward you with a crooked flower.
- Plant the bulb 2-2½ times deeper than the width of the bulb. Obviously, this rule doesn't apply to surface grown plants like Amaryllis and Iris
- Remove spent flowers promptly, but always allow the foliage to continue to grow until it dies back naturally. The foliage produces the nutrients needed to provide the next years flowers
- Most bulbs should only be divided in early spring or the fall while they are dormant.
- As a general rule, the colder your climate, the earlier you plant your spring flowering bulbs. In colder northern climates, | Plant in September or October. In warmer planting zones you may need to wait to plant bulbs until December or later.
- How to Plant, Grow and Care for Flowering Bulbs in Your Landscape
- How to Force Bulbs to Bloom Indoors and Out of Season
The planting depths indicated below are to the top of the bulb, NOT the depth of the hole!
Spring Flowering Bulbs
Name:
Crocus (corm)
Bloom time, Planting time, Hardiness: Blooms early spring
| Plant in fall
| Zones 3-9
Height: 3-6"
Planting: Plant 2-3" deep
Plant 2-4" apart
Can be forced to bloom
Looks best when grown in clusters
Name:
Daffodil Narcissus
Bloom time, Planting time, Hardiness: Blooms early spring
| Plant in fall
| Zones 4-9
Height: 6-15"
Planting: Plant 3-6" deep
Plant 3-8" apart
Can be forced to bloom
Flowers should be snapped off, not cut.
Name:
Bluebells Scilla siberica (bulb)
Bloom time, Planting time, Hardiness: Blooms early spring
| Plant in Sept/Oct
| Zones 3-9
Height: 4-8"
Planting: Plant 2-3" deep
Plant 3-5" apart
Evergreen where hardy.
Bluebells are excellent for naturalizing.
Name:
Silver Shamrock Oxalis adenophylla (bulb)
Bloom time, Planting time, Hardiness: Blooms early spring
| Plant in fall
| Zones 4-10
Height: 3-4"
Planting: Plant 1½-2" deep
Plant 2-4" apart
Beautifully pleated, silvery-blue foliage. Easily maintained.
Name:
Grape Hyacinth Muscari (bulb)
Bloom time, Planting time, Hardiness: Blooms early spring
| Plant in fall
| Zones 3-9
Height: 5-8"
Planting: Plant 2" deep
Plant 2-4" apart
Can be forced to bloom
Small, long lived bulbs. Best planted in masses.
Name:
Hyacinth Hyacinthus (bulb)
Bloom time, Planting time, Hardiness: Blooms early spring
Plant Sept-Nov
| Zones 3-9
Height: 12"
Planting: Plant 4-6" deep
Plant 6-8" apart
Can be forced to bloom
Grows well in planters
Very fragrant flowers.
Name:
Glory of Snow Chionodoxa (bulb)
Bloom time, Planting time, Hardiness: Blooms early spring
| Plant in Sept-Oct
| Zones 4-9
Height: 8"
Planting: Plant 3" deep
Plant 2-3" apart
Look best when planted in masses. Performs best in cold winter regions.
Name:
Lily of the Valley Convallaria majalis (rhizome)
Bloom time, Planting time, Hardiness: Blooms in early spring
| Plant in fall
| Zones 3-9
Height: 5-10"
Planting: Plant 1½-2" deep
Plant 2-4" apart
Can be forced to bloom
Sweetly scented flowers, likes partial to full shade.
Name:
Orange Star Ornith. dubium (bulb)
Bloom time, Planting time, Hardiness: Blooms early spring
| Plant in fall
| Zones 9-10
Height: 12-18"
Planting: Plant 1 per 5" pot with only base of bulb covered
Can grow as House Plant
Produces upright clusters of fragrant 1-2" flowers.
Name:
Tulip Tulipa (bulb)
Bloom time, Planting time, Hardiness: Blooms in spring
| Plant in fall
| Zones 3-8
Height: 10-20"
Planting: Plant 4-6" deep
Plant 4-8" apart
Grows well in planters
Cultivated in Europe since 1554
Name:
Crown Imperial Fritillaria (bulb)
Bloom time, Planting time, Hardiness: Blooms mid spring
| Plant in early fall
| Zones 5-9
Height: 3-4 ft.
Planting: Plant 6-8" deep
Plant 4-8" apart
Cultivated since the 16th century. Grows very quickly.
Name:
Fire Lily Clivia miniata (bulb-like)
Bloom time, Planting time, Hardiness: Blooms in spring
| Plant in spring
| Zones 10-11
Height: 12-18"
Planting: Plant up to root crown
Plant 2 ft. apart
Can grow as House Plant
Will bloom better when root bound.
Name:
Windflower Anemone blanda (tuber)
Bloom time, Planting time, Hardiness: Blooms in spring
| Plant in fall
| Zones 6-9
Height: 8"
Planting: Plant 1" deep
Plant 6" apart
Long blooming flowers above dense cover of fern-like foliage.
Name:
Freesia (bulb)
Bloom time, Planting time, Hardiness: Blooms in spring
Plant early fall
| Zones 9-10
Height: 12-18"
Planting: Plant 2" deep
Plant 2" apart
Can be forced to bloom
Can grow as House Plant
Easy to care for bulbs.
Name:
Gloxinia Sinningia hybridus (tuber)
Bloom time, Planting time, Hardiness: Blooms in spring
Plant Dec-March
| Zones 10-12
Height: 8-12"
Planting: Plant 1" deep
Plant 1 per 5" pot
Can grow as House Plant
Many foliage and flower forms and colors.
Name:
Dutch Iris Iris reticulata (bulb)
Bloom time, Planting time, Hardiness: Blooms in spring
| Plant in fall
| Zones 3-10
Height: 6-10"
Planting: Plant 3" deep
Plant 6" apart
Can be forced to bloom
Fragrant, tubular purple flowers
Name:
Japanese Iris Iris japonica (rhizome)
Bloom time, Planting time, Hardiness: Blooms late spring
Plant July-Oct
| Zones 8-11
Height: 12-24"
Planting: Plant 2" deep
Plant 12" apart
Foliage resembles that of a Daylily. Produces masses of crested flowers.
Name:
Siberian Iris Iris Siberica (rhizome)
Bloom time, Planting time, Hardiness: Blooms in late spring
| Plant in early spring or late summer
| Zones 4-9
Height: 2-4 ft.
Planting: Plant 1-2" deep
Plant 1-2 ft. apart
Very durable and extremely hardy plants.
Long blooming period.
Name:
Shamrock Oxalis oregona (bulb)
Bloom time, Planting time, Hardiness: Blooms late spring
| Plant in late summer
| Zones 8-10
Height: 6-8"
Planting: Plant 1-2" deep
Plant 2-4" apart
Can grow as House Plant
Easy to grow in light shade, never direct sun.
Name:
Jack in the Pulpit Arisaema (tuber)
Bloom time, Planting time, Hardiness: Blooms in late spring
| Plant in fall-winter
Zones vary
Height: 12-30"
Planting: Plant 4 " deep
Plant 12" apart
Compound, green or variegated leaves divided into 3-30 leaflets
Name:
Persian Buttercup Ranun. asiaticus (tuber)
Bloom time, Planting time, Hardiness: Blooms late spring
| Plant in fall
| Zones 8-10
Height: 8-18"
Planting: Plant 2" deep
Plant 6-8" apart
Grows well in planters
3"-5" Camellia-like flowers.
Name:
Peruvian Lily Alstroemeria (tuber)
Bloom time, Planting time, Hardiness: Blooms late spring
| Plant in fall
| Zones 7-10
Height: 2-3 ft.
Planting: Plant 6-8" deep
Plant 12" apart
Can grow as House Plant
Speckled flowers
Low maintenance
Long lived plant
Summer Flowering Bulbs
Name:
Star of Bethlehem Ornith. arabicum (bulb)
Bloom time, Planting time, Hardiness: Blooms early summer
| Plant in September
| Zones 7-10
Height: 12"
Planting: Plant 4" deep
Plant " apart
Produces upright clusters of fragrant 1-2" flowers.
Name:
Flowering Onion Allium species (bulb)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in fall
Zones vary
Height: 1-6 ft.
Planting: Plant 2-3x bulb size deep
Plant 4-6" apart
1"-5" flower clusters with dozens of star shaped flowers.
Name:
Bearded Iris Iris germanica (rhizome)
Bloom time, Planting time, Hardiness: Blooms in summer
Plant July-Oct
| Zones 4-10
Height: 6-48"
Planting: Plant with top at soil surface
Plant 12" apart
Almost every color imaginable, some scented varieties
Name:
Dragon Lily Dracunculus (bulb)
Bloom time, Planting time, Hardiness: Blooms summer
| Plant in fall
| Zones 5-8
Height: 18-24"
Planting: Plant 6" deep
Plant 9-12" apart
Also known as a Voodoo Lily and Stink Lily.
Name:
Caladium Colocasia (tuber)
Bloom time, Planting time, Hardiness: Foliage plant
Plant outdoors May
| Zones 10-11
Height: 12-18"
Planting: 2-3"
Plant 1 per 5-6" pot
Can grow as House Plant
Foliage is usually a combination of colors
Name:
Calla Lily Zantedeschia (rhizome)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in spring or fall
| Zones 8-11
Height: 2-4 ft.
Planting: Plant 4-6" deep
Plant 12-18" apart
Can be forced to bloom
Large, lush green foliage and stately flowers
Name:
Canna Lily Canna generalis (tuber)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in May or June
| Zones 8-11
Height: 3-6 ft.
Planting: Plant 5" deep
Plant 12-18" apart
Grows well in planters
Intensely colored flowers on 3-8 ft. spikes
Name:
Gladiola Gladiolus (corm)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in spring
| Zones 8-11
Height: 12-36"
Planting: Plant 4" deep
Plant 4" apart
Easy care, tall spikes of brightly colored flowers.
Name:
Lilies Lilium (bulb)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in fall
Zones vary
Height: 12-30"
Planting: Planting depth varies
Plant 6-12" apart
Very fragrant flowers. Many species and hybrids
Name:
Lily of the Nile Agapanthus (tuber)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in spring or fall
| Zones 9-11
Height: 18-36"
Planting: Plant 2" deep
Plant 6" apart
Grows well in planters
Agapanthus don't like their roots disturbed
Name:
Montbretia Crocosmia (corm)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in May or June
| Zones 7-11
Height: 2-4 ft.
Planting: Plant 3-5" deep
Plant 4-6" apart
Name:
Water Lily Nymphaea (tuber)
Bloom time, Planting time, Hardiness: Blooms in summer
| Plant in spring
Zones vary
Height: low
Planting: | Plant in wide pot
Submerge 18-36"Plant 1 per pot
Can be grown in sunken pots in your pond or a tub on your patio.
Name:
Dahlia Dahlia (tuber)
Bloom time, Planting time, Hardiness: Blooms in late summer
| Plant in late spring
| Zones 7-11
Height: 1-6 ft.
Planting: Plant 6" deep
Plant 1-3 ft. apart
A blast of different colors, shapes and sizes, flowers can be from 2"-12" in diameter.
Name:
Chocolate Cosmos C. atrosanguineus (tuber)
Bloom time, Planting time, Hardiness: Blooms summer/fall
| Plant in spring
| Zones 7-10
Height: 18"
Planting: Plant 6" deep
Plant 12" apart
Long blooming, Pleasant chocolate fragrance.
Name:
Reiger Begonia B. tuberhybrida (tuber)
Bloom time, Planting time, Hardiness: Blooms summer/fall
| Plant in early spring
| Zones 3-9
Height: 8-24"
Planting: Plant 1" deep
Plant 12" apart
Can grow as House Plant
Blooms for several months.
Name:
Spider Lily Lycoris radiata (bulb)
Bloom time, Planting time, Hardiness: Blooms late summer-fall
Plant late summer
| Zones 7-10
Height: 12-18"
Planting: Plant 3-6" deep
Plant 4-6" apart
Clusters of brilliant red flowers appear seemingly overnight
Fall and Winter Flowering Bulbs
Name:
Autumn Crocus Colch. autumnale (bulb)
Bloom time, Planting time, Hardiness: Blooms in fall
| Plant in late summer
| Zones 5-9
Height: 5-6"
Planting: Plant 3-4" deep
Plant 6-9" apart
Can be forced to bloom
Larger flowers than spring blooming Crocus
Name:
Fairy Lily Zephyranthes (bulb)
Bloom time, Planting time, Hardiness: Blooms in fall
| Plant in summer
| Zones 8-11
Height: 5-8"
Planting: Plant 1-2" deep
Plant 3" apart
Can be forced to bloom
Has a tendency in the wild to bloom after a rainfall.
Name:
Cyclamen Cyclamen persicum (corm)
Bloom time, Planting time, Hardiness: Blooms fall & spring
| Plant in June-Aug.
| Zones 5-7 / 9-10
Height: 2-5"
Planting:
Tender: Plant ½ of bulb above soil
Hardy:½" deep
Plant 4-8" apart
Can grow as House Plant
Needs cool temperatures, fresh air, and moisture.
Name:
Amaryllis Hippeastrum (bulb)
Bloom time, Planting time, Hardiness: Blooms in winter
| Plant indoors in
Nov-Dec
| Zones 9-11
Height: 1-2 ft.
Planting: Plant up to neck of bulb
Plant 1 per 5" pot
Can be forced to bloom
Can grow as House Plant
Giant 4-6" flowers
Name:
Snowdrops Galanthus (bulb)
Bloom time, Planting time, Hardiness: Blooms late winter
| Plant in fall
| Zones 3-9
Height: 6"
Planting: Plant 3-4" deep
Plant 2-3" apart
Each stem holds a single, nodding, bell-shaped, fragrant white flower.
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