It’s hard to believe we are 11 weeks away from Thanksgiving Day, which means for most, the first freeze date might be right around the corner. It may be hot and dry now, but cooler weather is on the way, and fall and winter gardening becomes more challenging with cooler temperatures. Awareness of frost and freeze dates will make your gardening less demanding as the days shorten and temperatures drop. Frost-free days are the gardening window you have to produce food and a beautiful landscape.
A frost date is defined as the day when the chance of the ground being frost free is 50%. They are determined using data from the past 30 years supplied by the Department of Agriculture. This frost date is defined as any day the temperature reaches 36 degrees F or below. Frost can kill plants even when the ground remains warm, but about the ground, it’s colder. As a result, you will see the tops of your plants die while the bottom looks great.
A freeze date is any day when the temperature falls below 32 degrees F. Freeze dates cause much more damage to our plants the frost dates. Below is the damage you can expect from various freeze-date temperatures.
1. Temperatures between 29 – 32 degrees F kill tender plants, but other plants will not show damage.
2. Temperatures between 25 – 28 degrees F are widely destructive and heavily damage tender and semi-hardy plants.
3. A temperature of 24 degrees F and below will heavily damage almost all plants.
How To Use This Information
The key to frost and freeze dates is knowing when you can start planting and when you need to complete your harvest. Of course, these are not perfect numbers. But, they are a guide to help you plan; timing is usually everything. Plant too early, and your plants could be weakened by cold temperatures making them more prone to pests and diseases. Plant too late, and plants might not reach maturity before the first frost.
Below is a graphic for big-picture planning purposes.
Here you can find a first freeze guide based on your zip code:
The Old Farmer’s Almanac
National Garden Association
We must overcome many challenges to be successful growers and water managers. It is sometimes overwhelming to see how the odds are stacked against us. However, with tools like this one and the other technology tools we discuss in our blogs and webinars, we can shift the odds in our favor.