Garden Planting Guide: When to Plant Seeds and Seedlings for Your Region

Enlarge Image Image Gallery To estimate the last spring frost date for your region, use this map. Illustration Courtesy Mother Earth News

Now is the perfect time to plan your greatest garden ever, and one of the best ways to ensure success is to plan ahead about when you’ll plant what. Some plants thrive in cooler soils, while others will only think about growing when it’s warmer. It’s important to plant your garden seeds and transplants at the right time so they can benefit from appropriate temperatures. New gardeners may want to begin by using purchased seedlings from a garden center or mail-order company, while those with proven green thumbs often like to start seeds indoors in advance of the garden season. Either way, this handy Spring Garden Worksheet will help you put the right plants into the ground at the right time.

Spring Garden Planting Guide

Step 1: Determine your last spring frost date 

To estimate your date, use the range of dates on the map in the Image Gallery. For a more precise date that takes microclimates into consideration, visit the National Climatic Data Center. (Your best bet is to choose their listing of a 90 percent probability of a freeze-free period.)

The spring frost-free date in my garden is ___________.

Step 2: Calculate planting dates 

If you want to start with seedlings: 

Get out a calendar and, for each crop, add or subtract the number of weeks in column 2 of the worksheet (“Safe Setting-Out Time”) from your frost-free date. Record these dates in column 3 (“Setting-Out Date”). This is the date it should be safe to plant your seedlings outside. Learn more about how to successfully transplant seedlings to your garden beds in "How to Transplant Seedlings."

If you want to start your own seeds: 

Take each date from column 3 (“Setting-Out Date”), subtract the number of weeks shown for that crop in column 4 (“Start Seeds Indoors”) and record that date in column 5 (“Start Indoors Date”). That is the latest you should start those seeds indoors.

Remember to harden off your seedlings over the course of a week or so by exposing them to outdoor conditions for a few hours each day before you finally plant them. (Note: All of the plants listed, except slow-growers such as eggplants and peppers, can be direct-sown in the garden. If you start them indoors, however, you can gain an earlier and sometimes better harvest. For the best results, start most seeds in a warm location (70 to 80 degrees) but move them to a cooler location (60 to 65 degrees) as soon as they sprout. Be sure all have adequate light.