One of the first steps you take when you are figuring out 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.

You can estimate when it's the best time to plant evolvulus in Portland by looking at the USDA zone info.

Planting Calendar for Evolvulus

Frost tolerance for evolvulus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's not a good idea to plant evolvulus until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant evolvulus in Portland is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant evolvulus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your evolvulus may not have a chance to fully mature. Starting your evolvulus indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Portland. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Portland is just an average the actual date of last frost will vary from year to year. Since half of the time in Portland it frosts late in the year after April 15 be ready to cover your evolvulus in the event of a surprise late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Portland

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