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.

You should be able to determine when it's the best time to plant garlic by referring to the USDA zone info for Ottawa.

Planting Calendar for Garlic

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

You can plant garlic much earlier in the year because they do well in cold.

The earliest that you can plant garlic 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 garlic and expect a good harvest is probably September. If you wait any later than that and your garlic may not have a chance to really do well. If you are starting your garlic indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Ottawa may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Ottawa it frosts late in the year after April 15 so always be ready to protect your garlic if you have a late frost.

USDA Zone Info for Ottawa

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Ottawa

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