One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Pullman should be read to estimate when to plant calibrachoa.

Planting Calendar for Calibrachoa

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

Calibrachoa are barely cold tolerant which means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant calibrachoa in Pullman 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 calibrachoa and expect a good harvest is probably August. If you wait any later than that and your calibrachoa may not have a chance to grow to maturity. Starting your calibrachoa indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Pullman. In the coldest months of winter you should expect an average low temperature of -5°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Pullman and it changes from year to year. Half of the time in Pullman there is a last frost after April 15 so just be sure to be ready to cover your calibrachoa in the event of a late frost.

USDA Zone Info for Pullman

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Pullman

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