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

By referring to the USDA zone info for Winthrop Harbor it's a good idea to estimate 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.

Yarrow are very cold tolerant which means that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant yarrow in Winthrop Harbor 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. Any later than that and your yarrow may not have a chance to grow to maturity. If you are starting your yarrow indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Winthrop Harbor. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Winthrop Harbor is an average and the actual date of last frost will vary from year to year. Since half of the time in Winthrop Harbor there is a last frost after April 15 be ready to protect your yarrow if you have a late frost.

USDA Zone Info for Winthrop Harbor

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 Winthrop Harbor

You may be interested in your other planting guides for Winthrop Harbor.