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.

The best time to plant achillea in Lancaster should be estimated by looking at the USDA zone info.

Planting Calendar for Achillea

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

Since achillea are very cold tolerant you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant achillea in Lancaster 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. You probably don't want to wait any later than that or else your achillea may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your achillea indoors.

Last Frost Date

The average date of last frost is April 15 in Lancaster. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Lancaster is an average the actual date of last frost changes from year to year. Since half of the time in Lancaster you get surprised by a frost after April 15 be ready to cover your achillea in the event of a late frost.

USDA Zone Info for Lancaster

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 Lancaster

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