What emergency measures help during unexpected frosts?
Written by
Benjamin Miller
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Unexpected frost events require a quick response with any materials you can scrounge together. Use blankets, cardboard boxes, or even newspaper as immediate plant covers. If possible, spray anti-transpirant on any exposed leaves. Harvest any fruits that are ripening. Water your plants deeply with warm (not hot or cold) water to insulate the soil. These steps can avert disaster if the forecast is wrong!
Immediate Coverage
- Drape blankets over plants before frost settles
- Use cardboard boxes for individual plants
- Weight edges with rocks or bricks
Harvest Protection
- Pick all mature vegetables and fruits
- Store in cool dark place immediately
- Cover remaining plants with row covers
Soil Treatment
- Water deeply with 60-70°F water
- Apply 1 gallon per square foot
- Cover watered soil with mulch
If you spray anti-transpirant sprays on your leaves 24 hours prior, a restorative barrier will form on those leaves. It has been shown to reduce moisture loss from 30-50%. I always keep a bottle handy for frost. I can spray it on when there is a surprise dip in temperature. I saved my azaleas with an anti-transpirant spray in a freak dip in temperature last spring.
Easily create microclimates with water-filled containers. Use black buckets or jugs to elevate the temperature next to desired plants. Fill containers with warm water just before sunset. The water will release stored heat through the night. In terms of temperature, this provides a few important degrees of protection when you don't have adequate covers.
After a surprise frost, check the damage first thing in the morning. Remove frost protection covers when the temperature rises above freezing. Check for any ice-damaged foliage, but do not prune ice-damaged stems right away. Give the plants some gentle morning sun exposure. Water the roots, ensuring that the foliage remains dry. Most plants will recover well with good aftercare after emergency protection.
Create an emergency kit before freeze season arrives, with old blankets, cardboard, and jugs of water all in one place. Keep anti-transpirant spray handy. I have a frost-protection bin in my garage. When cold comes at me unexpectedly, this level of preparation turns panic into action.
Read the full article: How to Protect Plants from Frost Effectively
