Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when it's the best time to plant columbine by using the USDA zone info for Markham.

Planting Calendar for Columbine

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

Columbine are moderately cold tolerant which means that you can start planting them earlier than more sensitive plants.

The earliest that you can plant columbine in Markham 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 columbine and expect a good harvest is probably September. Any later than that and your columbine may not have a chance to grow to maturity. Starting your columbine indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Just be sure to remember that USDA zone info for Markham may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Markham there is a last frost after April 15 be ready to protect your columbine if you have a late frost.

USDA Zone Info for Markham

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 Markham

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