When to Plant Pumpkins
Planting season for pumpkins hinges on one simple fact: knowing what kind of pumpkins you’re growing. Some pumpkin plants, such as the traditional carving types, need a long growing season of roughly 120 days. Planting pumpkins like the miniature varieties can wait until even July 1, because these pumpkins need only 90 days to mature.
The secret to knowing when to plant pumpkins lies on the seed packet. Look for the words “days to maturity.” For all but giant pumpkins, the number of days to maturity usually lies somewhere between 90 and 125 days. That means you want to plant your pumpkins so that the vines will have the right number of days between planting and harvest time to grow full-size, mature pumpkins.
Maybe you’re growing pumpkins for holiday displays. In that case, you might want to aim for an October 1 harvest date. Get the days to maturity figure from the seed packet and count backwards from October 1 to find your planting date. If you’re raising pumpkins for Thanksgiving or winter feasting, you might want a later harvest date. This is where things can get tricky.
If you garden where fall brings frost, find out what your area’s average first frost date is. This represents the date by which frost occurs 50 percent of the time. You can find this information at the National Climatic Data Center, where you can also find the 10 percent probability of a frost after a particular date.
Once you have that first fall frost date, you can get your planting date by counting backwards the number of days your pumpkin needs to grow to maturity (days to maturity). Life is simple if that planting date falls in the timeframe after your area’s last average spring frost. If not, you’ll either need to choose a pumpkin variety that matures in shorter growing window or start seeds pumpkins indoors.
Why is the frost date so important? Because pumpkins hate cold weather. Frost of any kind sounds a death knell for pumpkins—for plants and fruits. This means you don’t want to set out pumpkin plants too early in the growing season. If there’s still a chance of frost where you garden, it’s too soon for planting pumpkins. On the other end of the growing season, you want to be sure your pumpkin has ample time to mature before frost arrives.
For most jack o’lantern, carving, and pie pumpkins, you can safely tuck seeds into soil between May 15 and June 15, based on your area’s average last spring frost. Miniature pumpkins mature in a shorter growing season, so you can wait to plant those from May 25 until as late as July 1, depending on when the first fall frost typically occurs.
If you’re facing a short growing season or simply want to be sure you grow the largest pumpkin possible, you can start seeds indoors up to two weeks before your projected planting date. Pumpkin seedlings are fussy about transplanting into the garden. Use a biodegradable peat pot or newspaper pot to house your seedling. Be sure to give seedlings as much sunlight as possible so they don’t get spindly.