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.

A way of getting a good idea when to plant yarrow is to use the USDA zone info for Ames.

Planting Calendar for Yarrow

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

Yarrow do ok in a bit of cold which tells us that 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 Ames 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. Any later than that and your yarrow may not have a chance to fully mature. You can get started a little bit earlier by starting your yarrow indoors.

Last Frost Date

The average date of last frost is April 15 in Ames. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Ames may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Ames you get surprised by a frost after April 15 be ready to protect your yarrow if you have one of those late frosts.

USDA Zone Info for Ames

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 Ames

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