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

It's possible to figure out when it's possible to plant lisianthus by reviewing the USDA zone info for Walla Walla.

Planting Calendar for Lisianthus

Frost tolerance for lisianthus:	Not tolerant of frost.
When to plant:	After the last frost.

It's not a good idea to plant lisianthus until after the last frost because they do not do well in cold weather.

The earliest that you can plant lisianthus in Walla Walla 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 lisianthus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your lisianthus may not have a chance to grow to maturity. If you are starting your lisianthus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Walla Walla. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Walla Walla is not always accurate the actual date of last frost is different every year. Since half of the time in Walla Walla it frosts late in the year after April 15 be ready to protect your lisianthus in the event of a surprise late frost.

USDA Zone Info for Walla Walla

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Walla Walla

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