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 best time to plant fennel in Ottawa should be determined by checking out the USDA zone info.

Planting Calendar for Fennel

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

Fennel tend to make it in cold weather which means that you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant fennel in Ottawa 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. If you wait any later than that and your fennel may not have a chance to really do well. 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

On average the last frost has passed is on April 15 in Ottawa. In the coldest months of winter you should expect an average low temperature of -10°F.

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

USDA Zone Info for Ottawa

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 Ottawa

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