One of the best tools that you have as gardeners to help us determine 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 USDA zone info for Rialto should be looked at to figure out when you can plant erysimum.

Planting Calendar for Erysimum

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

Since erysimum are moderately cold tolerant you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant erysimum 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 erysimum and expect a good harvest is probably October. You probably don't want to wait any later than that or else your erysimum may not have a chance to grow to maturity. Starting your erysimum indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Rialto is just an average the actual date of last frost will vary from year to year. Half of the time in Rialto there is a last frost after January 31 so be sure to be ready to protect your erysimum in the event of a late frost.

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.