One of the best tools that you have as gardeners to help us figure out 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.

A way of getting a good idea when it's possible to plant romanesco is to refer to the USDA zone info for Rialto.

Planting Calendar for Romanesco

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

Since romanesco do well in moderate cold you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant romanesco 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 romanesco and expect a good harvest is probably October. Any later than that and your romanesco may not have a chance to really do well. Starting your romanesco indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in Rialto. In the coldest months of winter you can 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 can change quite a bit from year to year. Since half of the time in Rialto last frost occurs after January 31 be ready to protect your romanesco in the event of 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.