One of the best tools that you have as gardeners to help us estimate 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.

You should be able to figure out when it's a good idea to plant plectranthus by looking at the USDA zone info for Ottawa.

Planting Calendar for Plectranthus

Frost tolerance for plectranthus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Plectranthus are not cold tolerant which means that it is necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant plectranthus in Ottawa is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant plectranthus and expect a good harvest is probably August. Any later than that and your plectranthus may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your plectranthus indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Ottawa and it can change quite a bit from year to year. Half of the time in Ottawa it frosts late in the year after April 15 so be sure to be ready to protect your plectranthus if you have one of those late frosts.

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.