Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to figure out when it's a good idea to plant chervil by referring to the USDA zone info for Portland.

Planting Calendar for Chervil

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

Chervil are barely cold tolerant which means that you can plant them slightly earlier than plants that are more sensitive to the cold.

The earliest that you can plant chervil in Portland 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 chervil and expect a good harvest is probably August. If you wait any later than that and your chervil may not have a chance to really do well. Starting your chervil indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Portland and it changes from year to year. Half of the time in Portland you get surprised by a frost after April 15 so be sure to be ready to protect your chervil if you have a late frost.

USDA Zone Info for Portland

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 Portland

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