Frost Protection For Bulbs: Tips For Protecting Spring Bulbs From Frost

Purple Bulbs Covered In Frost
crocus frost
(Image credit: Hortus)

Crazy and unusual weather, such as the drastic changes in recent winters, leaves some gardeners wondering how to protect bulbs from frost and freeze. Temperatures have warmed and so has the soil, so the bulbs think it is later in the season than it actually is. Warmer than normal temperatures cause some bulbs to bloom early and an unexpected frost or freeze can do damage when bulbs are in bloom. So will frost hurt spring bulbs? Keep reading to find out more about protecting spring bulbs from frost.

Will Frost Hurt Spring Bulbs?

Bulbs that normally bloom through snow, like muscari, snowdrops and crocus, don't need spring bulb frost protection. Frost protection for bulbs that like warmer temperatures may be prudent, though. While the actual bulb that is buried underground is usually not damaged, emerging foliage, buds and blooms can be nipped, and browning and wilting of flowers often results. You can sometimes avoid this by providing frost protection for bulbs.

Spring Bulb Frost Protection

Spring bulb frost protection can be addressed at the time of planting by adding a 2-4 inch (5-10 cm.) layer of mulch. Research shows that more than 4 inches (10 cm.) offers no more protection and is basically a waste of money and effort.

Additional Tips for Protecting Spring Bulbs from Frost

Other methods are effective closer to the date of the projected frost/freeze event. Learn how to protect bulbs from frost following these tips:

  • Use a little hoop house. These are easily constructed by bending some pipe and attaching plastic as frost protection for bulbs.
  • Cover with fabric. Stake the area above the tallest plants and cover with a lightweight sheet or landscape fabric. Remove before the sun warms the area.
  • Use a cloche. A cloche, or even a one gallon milk jug, is an effective means of frost protection for bulbs that are blooming. Remove any covering in the morning as soon as temps rise.
  • Plant bulbs in a sheltered area. Planting near a home or building is a good method of spring bulb frost protection.
  • Cut buds and blooming flowers and bring inside. This is the most effective means of spring bulb frost protection, but does not preserve blooms in the garden.

Now that you've learned a little about spring bulb frost protection, apply these tips when they are applicable to your garden. Plant bulb types that are resistant to unexpected frosts and freezes so that you don't need to worry about extensive frost protection for bulbs.

Becca Badgett

Becca Badgett was a regular contributor to Gardening Know How for ten years. Co-author of the book How to Grow an EMERGENCY Garden, Becca specializes in succulent and cactus gardening.