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.

In Island Lake you can estimate when it's a good idea to plant achillea by looking at the USDA zone info.

Planting Calendar for Achillea

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

Achillea tend to make it in pretty solid cold which means that you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant achillea in Island Lake 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 achillea and expect a good harvest is probably September. If you wait any later than that and your achillea may not have a chance to grow to maturity. If you are starting your achillea indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Island Lake the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Island Lake is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Island Lake there is a last frost after April 15 be ready to cover your achillea if you have a late frost.

USDA Zone Info for Island Lake

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 Island Lake

You may be interested in your other planting guides for Island Lake.