The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to estimate when you can plant verbena by looking at the USDA zone info for Crookston.

Planting Calendar for Verbena

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

Verbena do ok in a tiny bit of cold which tells us that you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant verbena in Crookston 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 verbena and expect a good harvest is probably August. Any later than that and your verbena may not have a chance to fully mature. If you are starting your verbena indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Crookston. You should expect an average low temperature of -30°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Crookston and it will vary from year to year. Half of the time in Crookston last frost occurs after May 15 so be sure to be ready to protect your verbena in the event of a surprise late frost.

USDA Zone Info for Crookston

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 Crookston

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