Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Merrillville should be read to determine when it's a good idea to plant yarrow.

Planting Calendar for Yarrow

Frost tolerance for yarrow:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since yarrow are very cold tolerant you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant yarrow 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 yarrow and expect a good harvest is probably September. If you wait any later than that and your yarrow may not have a chance to really do well. If you are starting your yarrow indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Merrillville. In the coldest months of winter you should expect an average low temperature of -15°F.

It's important to remember that USDA zone info for Merrillville is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Merrillville you get a frost after April 15 so always be ready to protect your yarrow if you have 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.