One of the best tools that you have as gardeners to help us estimate 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 best time to plant chervil in Onalaska should be determined by using the USDA zone info.

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.

You can plant chervil a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant chervil in Onalaska 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 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 all chance of frost has passed is on May 15 in Onalaska. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Onalaska is just an average the actual date of last frost will vary from year to year. Since half of the time in Onalaska it frosts late in the year after May 15 be ready to protect your chervil if you have a late frost.

USDA Zone Info for Onalaska

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Onalaska

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