One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's possible to plant rhubarb is to look at the USDA zone info for Lathrop.

Planting Calendar for Rhubarb

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

Rhubarb do well in moderate cold which tells us that you can plant them earlier than more sensitive plants.

The earliest that you can plant rhubarb in Lathrop 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. Any later than that and your rhubarb may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your rhubarb indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Lathrop. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Lathrop may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Lathrop last frost occurs after February 15 so always be ready to cover your rhubarb if you have a surprise late frost.

USDA Zone Info for Lathrop

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 Lathrop

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