One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant calla lily in Tualatin can be determined by referring to the USDA zone info.

Planting Calendar for Calla Lily

Frost tolerance for calla lily:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Calla Lily are not cold tolerant which tells us that you need 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 Tualatin 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. You probably don't want to wait any later than that or else your calla lily may not have a chance to fully mature. You can get started a few weeks earlier by starting your calla lily indoors.

Last Frost Date

On average all chance of frost has passed is on March 15 in Tualatin. In the coldest months of winter you can expect an average low temperature of 15°F.

Since the USDA zone info for Tualatin is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Tualatin it frosts late in the year after March 15 so make sure that you are ready to protect your calla lily if you have a late frost.

USDA Zone Info for Tualatin

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 Tualatin

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