One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Mercer Island should be reviewed to figure out when it's possible to plant kale.

Planting Calendar for Kale

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

Kale are one of those plants that can tolerate a little bit of cold weather which means that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant kale 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 kale and expect a good harvest is probably September. If you wait any later than that and your kale may not have a chance to really do well. If you are starting your kale indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on 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 USDA zone info for Mercer Island is not always accurate and the actual date of last frost is different every year. Since half of the time in Mercer Island it frosts late in the year after March 15 be ready to cover your kale if you have 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.