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.

The best time to plant verbena in Walla Walla should be figured out by referring to the USDA zone info.

Planting Calendar for Verbena

Frost tolerance for verbena:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since verbena are barely cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

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

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

Last Frost Date

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

Since the USDA zone info for Walla Walla is just an average the actual date of last frost is different every year. Since half of the time in Walla Walla there is a last frost after April 15 be ready to protect your verbena if you have a 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.