Frost Protection Resources

With a stretch of cold weather coming up and many vegetable crops already planted, here are some resources on protecting your crop.

Rebecca Shortt – OMAFRA

Q. I don’t have complete sprinkler coverage and can’t frost protect (e.g. drip, traveling gun).  Should I irrigate before the frost event?

A. If the soil is dry then, YES, an irrigation today, BEFORE the soil cools, will help (can protect 1 degree C or so).  Do this before evening – you want the plants to be dry tonight.

Links:

Should I Irrigate Ahead of the Coming Freeze? – MSU

Irrigation For Frost Protection – OMAFRA

Frost Protection Tools – OMAFRA

Moist, non-cultivated soil retains more heat – MSU

Frost/Freeze protection using irrigation – Irrigation-Mart

Freezing crops and soil – Iowa State Extension

Anne Verhallen – OMAFRA
Comments on irrigation water temperature

• Where is the irrigation water coming from  – in regards to temperature – is it cooler than the soil currently (years ago researchers at Harrow looked at watering from the well on site – it actively cooled the soil which was a problem early on with tomatoes – and yes I realize they are more cold sensitive)
• What is the forecast in terms of sun – moist soil will hold heat but it needs sun to build heat (again years ago working with windstrips again in tomatoes, I never worried if we were sunny before a cold night – the worrisome ones were the cool cloudy days followed by the clouds disappearing and a cold clear night)

Effect of Different Soil Surfaces on Temperatures at 4 ft – Original Source