The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of determining when you can plant napa cabbage is to examine the USDA zone info for Rialto.

Planting Calendar for Napa cabbage

Frost tolerance for napa cabbage:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Napa cabbage do well in pretty solid cold which tells us that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant napa cabbage 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 napa cabbage and expect a good harvest is probably October. You probably don't want to wait any later than that or else your napa cabbage may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your napa cabbage indoors.

Last Frost Date

In Rialto the average date of last frost happens on January 31. In the coldest months of winter you can expect an average low temperature of 30°F.

Since the USDA zone info for Rialto is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Rialto you get a frost after January 31 be ready to protect your napa cabbage 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.