The USDA Zone info is a great tool for gardeners to help us estimate your gardening 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 coreopsis in Rialto should be figured out by reviewing the USDA zone info.

Planting Calendar for Coreopsis

Frost tolerance for coreopsis:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Coreopsis do ok in moderate cold which means that you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant coreopsis in Rialto is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant coreopsis and expect a good harvest is probably October. You probably don't want to wait any later than that or else your coreopsis may not have a chance to really do well. You can get started a little bit earlier by starting your coreopsis indoors.

Last Frost Date

On average the last frost is on January 31 in Rialto. In the coldest months of winter you should expect an average low temperature of 30°F.

It's important to remember that USDA zone info for Rialto is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Rialto you get a frost after January 31 be ready to protect your coreopsis if you have one of those late frosts.

USDA Zone Info for Rialto

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Rialto

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