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.

You will be able to figure out when it's a good idea to plant rhubarb by looking at the USDA zone info for Cupertino.

Planting Calendar for Rhubarb

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

You can plant rhubarb a little bit earlier in the year because they are moderately cold tolerant.

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

Last Frost Date

The average date of last frost is February 15 in Cupertino. You can expect an average low temperature of 25°F in the coldest months of winter.

Remember that USDA zone info for Cupertino is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Cupertino you get a frost after February 15 so make sure that you are ready to protect your rhubarb in the event of a surprise late frost.

USDA Zone Info for Cupertino

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Cupertino

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