The USDA Zone info is a great tool for gardeners to help us estimate 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.

You can estimate when it's a good idea to plant coreopsis in Grand Forks by referring to the USDA zone info.

Planting Calendar for Coreopsis

Frost tolerance for coreopsis:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since coreopsis are moderately cold tolerant you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant coreopsis in Grand Forks is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant coreopsis and expect a good harvest is probably August. If you wait any later than that and your coreopsis may not have a chance to fully mature. You can get started a little bit earlier by starting your coreopsis indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Grand Forks is just an average and the actual date of last frost is different every year. Half of the time in Grand Forks you get surprised by a frost after May 15 so make sure that you are prepared to protect your coreopsis in the event of a surprise 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.