First and Last Frost Dates

First and Last Frost Dates: A Comprehensive Guide by USDA Hardiness Zones

Knowing your first and last frost dates is key to planning a successful garden, as they determine when to plant and harvest your crops. But the best part is, you don't have to figure this out on your own! Park Seed's app From Seed to Spoon app takes care of all the calculations for you, making it easy to know exactly when to start planting, no matter where you live.

As the seasons transition and temperatures fluctuate, gardeners across the United States eagerly await the arrival of spring and dread the chill of autumn. One crucial factor in successful gardening is understanding the first and last frost dates specific to your USDA Hardiness Zone. You can find your Zone by entering your zip code on any of our product or category pages.

The USDA has more information about growing season lengths and dates based on averages. Find more here. 

Frost dates mark the beginning and end of the frost-free growing season, serving as a valuable reference point for garden planning. The last frost date in spring is the date after which the risk of frost is significantly reduced, making      it safer to transplant tender plants outdoors. The first frost date in fall, on the other hand, signifies the return of colder temperatures and the potential for frost damage to sensitive vegetation.    

USDA Hardiness Zones

Source: The Spruce

The USDA Hardiness Zone Map divides the United States into zones based on average minimum winter temperatures. Knowing your specific zone helps you determine the best plants to grow in your region and when to start planting. Park Seed's app, From Seed to Spoon, will calculate these dates for you and provide you with the ideal timing for garden tasks conveniently on your phone. And that's just one of the tools the app provides.  It will also help you identify pests and beneficials, learn about the nutrients your garden provides and how they help your overall wellness or support specific health issues.  

How to Use Frost Dates in Your Garden Planning

Understanding your frost dates is crucial for planning your garden activities effectively. Here are some practical tips to make the most of this information:

Spring Planning

Seed Starting: To get a head start on the growing season, some seeds can be started indoors. Begin starting seeds indoors 6-8 weeks before the last expected frost date.  However, some plants may have different requirements, so always check the specific instructions for your seed variety to ensure the best results when transplanting outdoors after the frost risk has passed. This gives you a head start on the growing season and allows you to transplant well-established seedlings once the risk of frost has passed. To make it easy, check the back of your seed packet or check the From Seed to Spoon app so you'll always know just when to plant. 

Transplanting Outdoors: Use the last frost date as a guideline for moving young plants from indoors to your garden. Tender plants like basil, tomatoes, and peppers should only be moved outside after the last frost date.

Frost Protection: For early spring plantings, consider using frost covers, cloches, or cold frames to protect sensitive seedlings from unexpected late frosts.

Fall Planning

Harvesting Crops: Plan to harvest tender crops before the first expected frost. Some vegetables, such as carrots and kale, can tolerate light frost and may even improve in flavor, but others need protection.

Overwintering Plants: Use the first frost date to determine when to start preparing your garden for winter. This includes mulching perennials, planting cover crops, and protecting delicate plants with row covers or bringing them indoors.

Planting for Winter: If you're fall seed starting for growing cool-season crops, such as garlic or spinach, use the first frost date to time your planting so that plants are established before the ground freezes.