One of the first steps you take when you are figuring out your gardening schedule is find your 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.

By using the USDA zone info for Ottawa it's a good idea to estimate when to plant lantana.

Planting Calendar for Lantana

Frost tolerance for lantana:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since lantana do not do well in cold weather you need to wait until after the last frost before you can plant them.

The earliest that you can plant lantana 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 lantana and expect a good harvest is probably August. If you wait any later than that and your lantana may not have a chance to fully mature. If you are starting your lantana indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Ottawa. It might get as low as -15°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Ottawa and it changes from year to year. Since half of the time in Ottawa there is a last frost after April 15 be ready to cover your lantana in the event of a surprise 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.