When to Plant Diascia in Cupertino, CA

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant diascia in Cupertino should be determined by using the USDA zone info.


Planting Calendar for Diascia

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

Diascia tend to make it in a little bit of cold which tells us that you can plant them a little bit earlier in the year than more sensitive plants.

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

The earliest that you can plant diascia 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 diascia and expect a good harvest is probably October. If you wait any later than that and your diascia may not have a chance to really do well. Starting your diascia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Cupertino may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Cupertino you get a frost after February 15 be ready to protect your diascia 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 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 Cupertino

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