One of the best tools that you have as gardeners to help us estimate 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.

A common way of making a decision about when it's a good idea to plant achillea is to examine the USDA zone info for Sullivan.

Planting Calendar for Achillea

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

You can plant achillea much earlier in the year because they do well in cold.

The earliest that you can plant achillea in Sullivan 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. You can get started a little bit earlier by starting your achillea indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Sullivan. In the coldest months of winter you can expect an average low temperature of -10°F.

Just be sure to remember that USDA zone info for Sullivan is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Sullivan you get surprised by a frost after April 15 so make sure that you are prepared to cover your achillea if you have one of those late frosts.

USDA Zone Info for Sullivan

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 Sullivan

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