The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant jerusalem artichokes in Washington should be figured out by referring to the USDA zone info.

Planting Calendar for Jerusalem artichokes

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

Jerusalem artichokes 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 jerusalem artichokes in Washington 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 jerusalem artichokes and expect a good harvest is probably September. Any later than that and your jerusalem artichokes may not have a chance to grow to maturity. If you are starting your jerusalem artichokes indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Washington the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Washington may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Washington it frosts late in the year after April 15 be ready to protect your jerusalem artichokes if you have a late frost.

USDA Zone Info for Washington

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 Washington

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