The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant cerastium in Mercer Island should be determined by reviewing the USDA zone info.

Planting Calendar for Cerastium

Frost tolerance for cerastium:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Cerastium are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant cerastium in Mercer Island 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 cerastium and expect a good harvest is probably September. Any later than that and your cerastium may not have a chance to really do well. If you are starting your cerastium indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Mercer Island. You can expect an average low temperature of 15°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Mercer Island and it is different every year. Since half of the time in Mercer Island there is a last frost after March 15 be ready to protect your cerastium in the event of one of those late frosts.

USDA Zone Info for Mercer Island

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

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

Plants to Grow in Mercer Island

You may be interested in your other planting guides for Mercer Island.