Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Union it's possible to figure out when it's the best time 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.

Since fennel are one of those plants that can tolerate quite a bit of cold weather you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant fennel in Union is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant fennel and expect a good harvest is probably September. Any later than that and your fennel may not have a chance to really do well. Starting your fennel indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Union. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Union is just an average the actual date of last frost will vary from year to year. Since half of the time in Union you get a frost after April 15 be ready to cover your fennel if you have a late frost.

USDA Zone Info for Union

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Union

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