One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

It's a good idea to determine when it's possible to plant yarrow by looking at the USDA zone info for Oak Park.

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 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 yarrow in Oak Park 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. You probably don't want to wait any later than that or else your yarrow may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your yarrow indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Oak Park. It might get as low as -10°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Oak Park may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Oak Park you get a frost after April 15 be ready to protect your yarrow if you have a surprise late frost.

USDA Zone Info for Oak Park

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Oak Park

You may be interested in your other planting guides for Oak Park.