The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Grand Forks can be looked at to determine when you can plant purple bell vines.

Planting Calendar for Purple Bell Vines

Frost tolerance for purple bell vines:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant purple bell vines a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant purple bell vines in Grand Forks 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 purple bell vines and expect a good harvest is probably August. You probably don't want to wait any later than that or else your purple bell vines may not have a chance to fully mature. Starting your purple bell vines indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Grand Forks. It might get as low as -30°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Grand Forks and it changes from year to year. Half of the time in Grand Forks it frosts late in the year after May 15 so always be ready to cover your purple bell vines if you have a late frost.

USDA Zone Info for Grand Forks

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Grand Forks

You may be interested in your other planting guides for Grand Forks.