Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. 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 ornamental grasses in Ottawa should be figured out by looking at the USDA zone info.

Planting Calendar for Ornamental Grasses

Frost tolerance for ornamental grasses:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Ornamental Grasses do ok in moderate cold which tells us that you can start planting them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant ornamental grasses in Ottawa 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 ornamental grasses and expect a good harvest is probably August. If you wait any later than that and your ornamental grasses may not have a chance to really do well. You can get started a few weeks earlier by starting your ornamental grasses indoors.

Last Frost Date

The average date of last frost is 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 may not be accurate from year to year the actual date of last frost 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 protect your ornamental grasses if you have one of those late frosts.

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.