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

The best time to plant columbine in Merrillville can be estimated by reviewing the USDA zone info.

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 tells us that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant columbine in Merrillville 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 really do well. Starting your columbine indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Merrillville. In the coldest months of winter you should expect an average low temperature of -15°F.

Remember that USDA zone info for Merrillville is just an average and the actual date of last frost is different every year. Half of the time in Merrillville you get a frost after April 15 so make sure that you are ready to protect your columbine in the event of a late frost.

USDA Zone Info for Merrillville

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 Merrillville

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