The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. 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 East Troy should be read to estimate when 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.

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

The earliest that you can plant yarrow in East Troy 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 really do well. 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

In East Troy the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for East Troy may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in East Troy you get surprised by a frost after April 15 so be sure to be ready to cover your yarrow in the event of one of those late frosts.

USDA Zone Info for East Troy

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in East Troy

You may be interested in your other planting guides for East Troy.