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.

The first opportunity to plant salpiglossis in Walla Walla can be figured out by using the USDA zone info.

Planting Calendar for Salpiglossis

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

Since salpiglossis are not cold tolerant it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant salpiglossis 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 salpiglossis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your salpiglossis may not have a chance to really do well. Starting your salpiglossis indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Walla Walla the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

Since the USDA zone info for Walla Walla is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Walla Walla it frosts late in the year after April 15 be ready to cover your salpiglossis 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.