One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. 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 purple bell vines in Washington can be estimated by referring to the USDA zone info.

Planting Calendar for Purple Bell Vines

Frost tolerance for purple bell vines:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since purple bell vines are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant purple bell vines in Washington is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant purple bell vines and expect a good harvest is probably August. You probably don't want to wait any later than that or else your purple bell vines may not have a chance to fully mature. If you are starting your purple bell vines indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Washington the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Remember that USDA zone info for Washington is an average and the actual date of last frost will vary from year to year. Half of the time in Washington you get a frost after April 15 so make sure that you are ready to cover your purple bell vines in the event of a surprise late frost.

USDA Zone Info for Washington

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Washington

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