One of the first steps you take when you are getting a good idea 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.

By reviewing the USDA zone info for Pullman it's a good idea to figure out when to plant calla lily.

Planting Calendar for Calla Lily

Frost tolerance for calla lily:	Not tolerant of frost.
When to plant:	After the last frost.

Calla Lily require warm weather which tells us that it's important to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant calla lily in Pullman 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 calla lily and expect a good harvest is probably August. Any later than that and your calla lily may not have a chance to really do well. You can get started a couple of weeks earlier by starting your calla lily indoors.

Last Frost Date

In Pullman the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Keep in mind that USDA zone info for Pullman is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Pullman you get a frost after April 15 so just be sure to be ready to protect your calla lily in the event of a surprise 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.