When to Plant Peonies in San Jose, CA

One of the first steps you take when you are figuring out your gardening schedule is find your 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.

The USDA zone info for San Jose should be read to estimate when to plant peonies.


Planting Calendar for Peonies

Frost tolerance for peonies: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

You can plant peonies slightly earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

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

The earliest that you can plant peonies in San Jose is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant peonies and expect a good harvest is probably September. You probably don't want to wait any later than that or else your peonies may not have a chance to grow to maturity. Starting your peonies indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In San Jose the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

It's important to remember that USDA zone info for San Jose is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in San Jose you get a frost after February 15 be ready to protect your peonies in the event of a surprise late frost.

USDA Zone Info for San Jose

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 Low25°F
Highest Expected Low30°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 San Jose

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