One of the best tools that you have as gardeners to help us determine 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.

One way of figuring out when it's the best time to plant alternaria is to use the USDA zone info for Chehalis.

Planting Calendar for Alternaria

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

It's a bad idea to plant alternaria until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant alternaria in Chehalis 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 alternaria and expect a good harvest is probably August. Any later than that and your alternaria may not have a chance to fully mature. If you are starting your alternaria indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Chehalis the average date of last frost happens on March 15. You should expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Chehalis is an average the actual date of last frost will vary from year to year. Half of the time in Chehalis you get a frost after March 15 so be sure to be ready to protect your alternaria if you have a surprise late frost.

USDA Zone Info for Chehalis

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Chehalis

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