When to Plant Coleus in Markham, IL

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.

A way of determining when it's the best time to plant coleus is to look at the USDA zone info for Markham.


Planting Calendar for Coleus

Frost tolerance for coleus: Not tolerant of frost.
When to plant: After all chance of frost has passed.

It's probably a bad idea to plant coleus until after the last frost when the weather gets warmer because they are not cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant coleus
Possibly ok, but a risky time to plant coleus
Probably not a good time to plant coleus

The earliest that you can plant coleus in Markham 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 coleus and expect a good harvest is probably August. Any later than that and your coleus may not have a chance to really do well. Starting your coleus indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Just be sure to remember that USDA zone info for Markham is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Markham it frosts late in the year after April 15 be ready to protect your coleus in the event of a surprise 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.