The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of determining when it's a good idea to plant four-o-clock flower is to check out the USDA zone info for Kelso.

Planting Calendar for Four-o-clock flower

Frost tolerance for four-o-clock flower:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since four-o-clock flower do not do well in cold weather you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant four-o-clock flower 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 four-o-clock flower and expect a good harvest is probably August. Any later than that and your four-o-clock flower may not have a chance to really do well. You can get started a few weeks earlier by starting your four-o-clock flower indoors.

Last Frost Date

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

Just be sure to remember that USDA zone info for Kelso is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Kelso you get surprised by a frost after March 15 so always be ready to cover your four-o-clock flower in the event of a 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.