Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Ashtabula can be reviewed to estimate when it's a good idea to plant achillea.

Planting Calendar for Achillea

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

Achillea are very cold tolerant which tells us that you can plant them a quite a bit earlier than other plants that might not handle the cold.

The earliest that you can plant achillea in Ashtabula 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 Ashtabula. In the coldest months of winter you can expect an average low temperature of -5°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Ashtabula and it changes from year to year. Half of the time in Ashtabula you get surprised by a frost after April 15 so make sure that you are prepared to cover your achillea if you have a late frost.

USDA Zone Info for Ashtabula

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Ashtabula

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