The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of estimating when you can plant lettuce is to look at the USDA zone info for Aspen.

Planting Calendar for Lettuce

Frost tolerance for lettuce:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant lettuce a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant lettuce in Aspen is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant lettuce and expect a good harvest is probably September. You probably don't want to wait any later than that or else your lettuce may not have a chance to grow to maturity. You can get started a little bit earlier by starting your lettuce indoors.

Last Frost Date

The average date of last frost is April 15 in Aspen. You can expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Aspen and it will vary from year to year. Half of the time in Aspen last frost occurs after April 15 so make sure that you are ready to protect your lettuce if you have one of those late frosts.

USDA Zone Info for Aspen

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 Aspen

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