In order to have healthy plants and successful blooms, bulbs must be planted at the proper depth and spacing. It always pays to spend a few extra minutes to get things planted correctly, but with bulbs it’s even more important – too deep, or too shallow, and your bulbs may fail to bloom or not even sprout at all.
Here’s what you need to know about the proper depths for planting spring bulbs.
In order to have healthy plants and successful blooms, bulbs must be planted at the proper depth and spacing. It always pays to spend a few extra minutes to get things planted correctly, but with bulbs it’s even more important – too deep, or too shallow, and your bulbs may fail to bloom or not even sprout at all. And if you crowd them, or plant them too sparsely, you’ll likely be disappointed with the overall effect.
Here are a few general guidelines to help you decide how to plant your bulbs:
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- Bulb Size: Most spring bulbs should be planted at a depth about three times the diameter of the bulb.
- Measure correctly: Depth refers to the bottom of the planting hole, where the base of the bulb will rest.
- Layering: Since different types of bulbs are planted at different depths, you can layer them in a planting bed for a naturalized, drifting look. Just make sure you don’t plant bulbs right on top of each other – give each one some room.
- Follow Instructions: If your purchased bulbs have planting instructions, by all means follow them. Some hybrids and special cultivars may vary from the typical recommended planting depths, so you’re better off following the grower’s advice rather than the list below.
Here are the recommended planting depths and spacing for a variety of popular spring bulbs:
| Plant: | Depth: | Spacing: |
|---|---|---|
| Allium, large | 6”- 8” | 6”- 12” |
| Allium, small | 3”- 4” | 3” |
| Anemone | 2”- 5” | 6” |
| Calla | 6”- 8” | 12” |
| Chionodoxa (Glory-of-the-Snow) | 3”- 4” | 3” |
| Crocus | 3”- 4” | 3” |
| Fritillaria meleagris | 3”- 5” | 4” |
| Fritillaria imperialis | 6”- 8” | 10”- 12” |
| Muscari (Grape hyacinth) | 3” | 3” |
| Hyacinth | 6”- 8” | 6” |
| Iris germanica (Bearded Iris) | 1” | 8”- 10” |
| Iris reticulata (Reticulated Iris) | 3”- 4” | 4” |
| Leucojum aestivum (Spring Snowflake) | 5” | 4” |
| Lily | 6”- 8” | 8”- 10” |
| Narcissus, large (Daffodil) | 6”- 8” | 6” |
| Narcissus, small (Narcissus, Daffodil) | 4”- 6” | 3”- 4” |
| Scilla | 3”- 5” | 4” |
| Galanthus (Snowdrop) | 3”- 4” | 3” |
| Tulip, garden | 6”- 10” | 4”- 6” |
| Tulip, species | 3”- 4” | 2”- 3” |
Further Information
- Guide to Growing Bulbs (article)
- Understanding the Types of Bulbs (article)
- Planting Bulbs (video)
- How to Plant Tulips and Other Flowering Bulbs (video)
