One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of getting a good idea when you can plant hollyhocks is to consult the USDA zone info for Grand Forks.

Planting Calendar for Hollyhocks

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

Since hollyhocks are moderately cold tolerant you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant hollyhocks 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 hollyhocks and expect a good harvest is probably August. If you wait any later than that and your hollyhocks may not have a chance to grow to maturity. If you are starting your hollyhocks indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Grand Forks the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -30°F.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Grand Forks and it can change quite a bit from year to year. Since half of the time in Grand Forks it frosts late in the year after May 15 be ready to cover your hollyhocks if you have 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.