One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant chervil in Longmont should be figured out by looking at 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.

Since chervil are barely cold tolerant you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant chervil in Longmont 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. You probably don't want to wait any later than that or else your chervil may not have a chance to fully mature. If you are starting your chervil indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Longmont the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Longmont is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Longmont you get a frost after April 15 so be sure to be ready to cover your chervil in the event of a late frost.

USDA Zone Info for Longmont

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 Longmont

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