The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. 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 figuring out when it's possible to plant achillea is to look at the USDA zone info for Lake Bluff.

Planting Calendar for Achillea

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

Since achillea are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant achillea in Lake Bluff 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. Any later than that and your achillea may not have a chance to fully mature. Starting your achillea indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Lake Bluff is just an average and the actual date of last frost changes from year to year. Half of the time in Lake Bluff you get a frost after April 15 so always be ready to protect your achillea if you have a surprise late frost.

USDA Zone Info for Lake Bluff

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 Lake Bluff

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