One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Wilmette can be read to determine when you can 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 can survive in cold weather which tells us that you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant yarrow in Wilmette 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 grow to maturity. Starting your yarrow indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Wilmette may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Wilmette it frosts late in the year after April 15 be ready to cover your yarrow in the event of a surprise late frost.

USDA Zone Info for Wilmette

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 Wilmette

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