When to Plant Rhubarb in San Marcos, CA

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant rhubarb in San Marcos can be determined by using the USDA zone info.


Planting Calendar for Rhubarb

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

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

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant rhubarb
Possibly ok, but a risky time to plant rhubarb
Probably not a good time to plant rhubarb

The earliest that you can plant rhubarb in San Marcos 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 fully mature. If you are starting your rhubarb indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on January 31 in San Marcos. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for San Marcos is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in San Marcos last frost occurs after January 31 be ready to protect your rhubarb if you have a surprise late frost.

USDA Zone Info for San Marcos

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 Low30°F
Highest Expected Low35°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 San Marcos

You may be interested in your other planting guides for San Marcos.