The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of determining when you can plant snow-in summer is to look at the USDA zone info for Walla Walla.

Planting Calendar for Snow-in Summer

Frost tolerance for snow-in summer:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since snow-in summer are moderately cold tolerant you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant snow-in summer in Walla Walla 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 snow-in summer and expect a good harvest is probably September. Any later than that and your snow-in summer may not have a chance to really do well. Starting your snow-in summer indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Walla Walla may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Walla Walla it frosts late in the year after April 15 so make sure that you are ready to cover your snow-in summer if you have one of those late frosts.

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.