Frost Watch Card
Post near the phone. When temps drop, you don't want to think.
Last frost date (10% risk): First frost date (10% risk):
If tonight's low is forecast below 36F:
- ☐ Check station forecast + NOAA forecast
- ☐ Row cover all tender transplants
- ☐ Turn on frost sprinklers if installed
- ☐ Hauled out tender potted trees/herbs
- ☐ Water well in late afternoon (wet soil holds heat)
- ☐ Close greenhouse / tunnel vents at 4pm
- ☐ Start heater on propagation benches
If forecast below 30F:
- ☐ All of the above, plus:
- ☐ Double row cover critical crops
- ☐ Plastic over hoop supports
- ☐ Drain irrigation lines if below 28F risk
- ☐ Leave water running low at one tap (prevent pipe freeze)
Day-after frost:
- ☐ Observe damage before watering
- ☐ Do NOT uncover until air temp > 40F
- ☐ Hose off iced leaves before sun strikes
- ☐ Record event in Field Journal
Crop frost thresholds (PNW region - adjust for yours)
| Crop |
Kills at |
| Basil, tomato, pepper, squash |
33F light damage, 30F kill |
| Bean, corn, cucumber |
32F |
| Lettuce, spinach, kale, chard |
28-32F damage, 25F hard loss |
| Broccoli, cabbage, brussels |
20-25F mature; seedlings 28F |
| Carrot, parsnip, leek |
sweeten after frost, 15F OK |
| Peas |
28F flower kill |
| Garlic, onion (field) |
10F OK if established |
Signed: Date: Initials: