One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant lavender in Ottawa should be estimated by using the USDA zone info.

Planting Calendar for Lavender

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

Since lavender are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than other frost tender plants.

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

Last Frost Date

In Ottawa the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Ottawa and it can change quite a bit from year to year. Since half of the time in Ottawa last frost occurs after April 15 be ready to cover your lavender in the event of 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.