The proper planting depth for spring-flowering bulbs is important for overall plant health as well as ensuring the bulbs will bloom. Different types of flowering bulbs need to be planted at different depths, but a good general rule of thumb is to plant the bulb at three times the height of the bulb. So, for example, if a bulb is two inches from tip to base, you'd plant it six inches deep.
Ideal Planting Depth by Bulb Type
When you purchase spring-flowering bulbs, follow the planting instructions on the bulb packaging. If you don't have that information, follow the standard recommended planting depths for some of the most common types of spring-flowering bulbs (planting depth is measured from the surface of the soil to the shoulder of the bulb):
3 to 4 Inches
- Crocus: 3 inches
- Muscari (Grape Hyacinth): 3 inches
- Snowdrop: 3 inches
- Glory of the Snow: 3 to 4 inches
- Siberian Squill (Scilla): 3 to 4 inches
- Spring Snowflake: 3 to 4 inches
- Striped Squill: 3 to 4 inches
- Quamash (Camassia): 4 inches
- Spanish bluebell: 4 inches
6 to 8 Inches
- Daffodil: 6 inches
- Tulips: 6 inches
- Hyacinth: 7 inches
- Fritillaria (Crown Imperial): 6 to 8 inches
- Large Allium bulbs: 8 inches
How and Where to Plant Bulbs
Spring-flowering bulbs are planted in the fall in containers or in garden beds. If you plant spring-flowering bulbs in containers, make sure the container has drainage holes and is the appropriate diameter based on the bulbs' growing instructions.
When planting spring-flowering bulbs in the ground, remove all weeds, rocks, and other debris from the area. Loosen the soil, and mix in some compost or other organic matter or add a slow-release fertilizer if the soil lacks nutrients.
A general rule for planting bubs is when a bulb has a pointy tip, such as tulips do, the pointy side goes up. If the bulb has sprouts but no pointy tip, the sprouting side goes up. Bulbs that have no discernible up or down side, such as anemones, can usually be planted in any direction and the sprouts will find their way to daylight.
Where you plant bulbs is equally as important as how deep they are planted. Most bulbs do best in well-drained, loamy soil in an area that receives at least six hours of full sun daily.
After planting, spread one to two inches of mulch over the bulbs to help to retain soil moisture and inhibit weeds. Don't forget to water the bulbs at initial planting time which will help develop their root system before winter sets in. Do not provide additional water after initial planting.
To prolong bloom time and create a beautiful effect, you can layer spring-blooming bulbs. Plant smaller and early-blooming bulbs such as crocus, grape hyacinths, and scilla on top of larger bulbs, like daffodils, hyacinths, and tulips. The larger bulbs go into the planting hole first, covered with a layer of soil, topped by the smaller bulbs planted a little closer to the soil surface.