Frost and storm response works only if it is prepared before the season: stock covers sized to the beds, name a call-out list, time a covering drill to learn how fast the crew covers an area, and decide in advance which crops are lifted and which are covered. On a clear, calm night the leaves can be colder than the forecast air temperature, and when lightning is near, field work stops.
Emergency response for frost and storms is the set of standing plans, stocks and drills that let a community protect crops at short notice.
Why Both Seasons Need A Plan
Late frost threatens the tender crops planted in May; early frost threatens the harvest that the carrier says must be finished before hard freeze in October (April-June, October-December). Storms, whether hail, flood or high wind, strike ripe crops, drying hay and cold frames. The time to prepare is not on the evening of the warning.
Frost: Know The Signs
Frost needs a clear sky, calm wind, a cold surface, low humidity and a long night; a breeze of 5-10 km/h can prevent it, and cold air flows downhill and pools in hollows (Frost Prediction, Cold Air Drainage and Frost Pockets). On such nights leaf surfaces radiate heat to the sky and can be a few degrees colder than the air at head height, so judge by a thermometer at plant height in your lowest beds, not by the forecast alone.
Tender crops (tomato, pepper, squash, cucumber, bean, basil) are damaged around 0 °C. Hardy crops such as kale, spinach and many roots tolerate frost and sweeten with it (Cold-Hardy Greens and Roots).
Frost Response Plan
| Stage | Trigger | Action |
|---|---|---|
| Watch | Clear, calm, dry forecast with lows near freezing | Check covers and tools; tell the call-out list |
| Warning | Afternoon temperatures falling and the sky clearing | Pick ripe tender crops; start covering |
| Act | Dusk | Finish covering; close cold frames and tunnel ends |
| Dawn | Frost on the ground | Leave covers on until the frost has melted, then remove |
Covering rules: use sheets, burlap, straw, or row-cover fabric, held clear of leaves and carried to the ground at the edges so that heat stored in the soil is trapped. Plastic lying on leaves conducts cold and burns them; keep it on hoops. Remove covers in the morning once the frost has thawed, so the plants do not overheat.
Harvest first: ripe tender crops are lifted before the night, and mature-green tomatoes can be ripened indoors.
Storms
- Lightning. The 30/30 rule from the Phase 0 guide: shelter immediately if thunder follows lightning in under 30 seconds, and wait 30 minutes after the last thunder before returning (Storm Safety). Stop field work, move people out of open ground and away from isolated trees, tall tools and metal fences.
- Hail and wind. Lift what is ready, tie down covers and stake tall crops, shut animals in, close cold-frame lids.
- Flood. Open drainage ditches in advance, move stored goods off floors.
- Hay. Do not cut hay with rain forecast within its drying period.
Plan The Labour Arithmetic
Time a drill in calm weather. Cover one area with a measured crew and find the rate in square metres per person-hour. Then:
time needed (hours) = area ÷ (rate × number of people).
Worked example (invented numbers to show the sum): 600 m² of tender crops, a drill rate of 100 m² per person-hour, and 10 people on the call-out list: 600 ÷ (100 × 10) = 0.6 hours, about 36 minutes. If the crew can only be assembled with a 30-minute delay, the covering must start at least 66 minutes before dusk. Replace the invented rate with your own, and repeat the drill each season with new people.
Stock And Roles
- Covers sized to beds, with an allowance for overlap; stored dry and labelled.
- Weights, stakes and hoops kept with the covers.
- A call-out list of named people, each with a role: lifters, coverers, animal shelter, water.
- A decision-maker for the evening who can say “cover now”.
- Skilled-job protection: do not pull the canning crew off a pressure run at the same time (Canning Production Timeline).
After The Event
Check for damage in two or three days, since frost-damaged leaves take time to show. Do not cut back at once. Resow crops that can still mature, using the planting window (Planting and Harvest Windows). Record the date, the lowest temperature and what worked.
Storm cleanup and night work
Lightning kills in open fields. After a storm, stay clear of downed power lines and fallen trees under strain, work in pairs when using saws, and keep out of floodwater, which hides holes and carries sewage. Covering crews working at dusk in the cold should carry lights and keep warm.
Common Mistakes
- Learning the covering rate on the night.
- Covers with no weights. They blow off.
- Uncovering late. Plants cook under cloth in morning sun.
- Ignoring the cold hollows. The lowest bed frosts first.
What’s Next
- Learn next: Root Cellar Loading Plan — storing what you save
- Combine with: Emergency Decisions — who decides in an emergency