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.

The USDA zone info for Glendive should be used to estimate when to plant fennel.

Planting Calendar for Fennel

Frost tolerance for fennel:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Fennel do well in cold which tells us that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant fennel in Glendive 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 fennel and expect a good harvest is probably August. You probably don't want to wait any later than that or else your fennel may not have a chance to fully mature. If you are starting your fennel indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Glendive 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.

Since the USDA zone info for Glendive is not always accurate the actual date of last frost changes from year to year. Since half of the time in Glendive you get surprised by a frost after May 15 be ready to protect your fennel in the event of one of those late frosts.

USDA Zone Info for Glendive

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 Glendive

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