Planting Depth and Spacing of Spring-flowering Bulbs

The array of spring-flowering bulbs includes tulips, daffodils, crocuses, hyacinths, snowdrops, and flowering onions.  By planting a variety of spring-flowering bulbs, gardeners can enjoy blooming plants from early April to mid-June. 
 
For best selection, visit your local garden center early.  Select large, firm bulbs.  Avoid soft or blemished bulbs.  Store purchased bulbs in a cool, dry location until they can be planted in the fall.  October is the ideal time to plant spring-flowering bulbs.  To achieve the greatest visual impact, plant spring-flowering bulbs in clusters or drifts.  When planting tulips or daffodils, plant 15 or more bulbs of the same variety in a cluster.  Smaller growing bulbs, such as Siberian squill, should be planted in drifts of 50 or more.  The following list provides planting depth and spacing of various spring-flowering bulbs. 
 
Bulb
Depth*
Spacing
 
 
 
Allium spp. (Ornamental Onion)
     large bulbs (A. giganteum and others)
     small bulbs (A. moly, A. unifolium, etc.)
 
6 inches
3 to 5 inches
 
12 to 18 inches
6 to 8 inches
Camassia spp. (Camas)
4 inches
4 inches
Chionodoxa luciliae (Glory-of-the-Snow)
3 to 4 inches
3 inches
Crocus spp. (Crocus)
3 to 4 inches
3 inches
Fritillaria spp. (Fritillaria)
     Fritillaria imperialis (Crown Imperial)
     F. meleagris & other small flowering types
 
6 to 8 inches
3 to 4 inches
 
12 to 18 inches
4 inches
Galanthus nivalis (Common Snowdrop)
3 to 4 inches
3 inches
Hyacinthoides hispanica (Spanish Bluebell)
4 inches
4 to 6 inches
Hyacinthus orientalis (Hyacinth)
6 inches
6 to 8 inches
Leucojum vernum (Spring Snowflake)
3 to 4 inches
3 to 4 inches
Muscari armeniacum (Grape Hyacinth)
3 to 4 inches
3 to 4 inches
Narcissus spp. (Daffodil)
     Trumpet, large-cupped, etc.
     Miniature and other small bulbs
 
6 to 8 inches
3 to 5 inches
 
6 to 8 inches
4 to 6 inches
Puschkinia scilloides (Striped Squill)          
3 to 4 inches
3 inches
Scilla siberica (Siberian Squill)
3 to 4 inches
3 inches
Tulipa spp. (Tulip)
     Darwin hybrid tulips, triumph tulips, etc.
     Species or botanical tulips
 
6 to 8 inches
3 to 5 inches
 
4 to 6 inches
3 to 4 inches
 
 
 
* Planting depth is measured from the base of the bulb to the soil surface
 
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