Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant blue throatwort in Kelso should be determined by reviewing the USDA zone info.

Planting Calendar for Blue Throatwort

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

Blue Throatwort require warm weather which tells us that you have to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant blue throatwort in Kelso 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 blue throatwort and expect a good harvest is probably August. If you wait any later than that and your blue throatwort may not have a chance to fully mature. Starting your blue throatwort indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Kelso may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Kelso you get a frost after March 15 be ready to cover your blue throatwort if you have a surprise late frost.

USDA Zone Info for Kelso

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Kelso

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