One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant pumpkins in Ottawa can be determined by reviewing the USDA zone info.

Planting Calendar for Pumpkins

Frost tolerance for pumpkins:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since pumpkins do not do well in cold weather it's necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant pumpkins in Ottawa is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant pumpkins and expect a good harvest is probably August. If you wait any later than that and your pumpkins may not have a chance to grow to maturity. If you are starting your pumpkins indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Ottawa. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Ottawa is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Ottawa you get surprised by a frost after April 15 so make sure that you are ready to protect your pumpkins if you have a late frost.

USDA Zone Info for Ottawa

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Ottawa

You may be interested in your other planting guides for Ottawa.