When to Plant Diascia in Redwood City, CA

One of the first steps you take when you are getting a good idea 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.

A common way of making a decision about when it's possible to plant diascia is to refer to the USDA zone info for Redwood City.


Planting Calendar for Diascia

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

Diascia are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them a little bit earlier than other frost tender 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 Redwood City 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. You probably don't want to wait any later than that or else your diascia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your diascia indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Redwood City. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Redwood City is not always accurate the actual date of last frost will vary from year to year. Half of the time in Redwood City there is a last frost after February 15 so make sure that you are ready to cover your diascia if you have a late frost.

USDA Zone Info for Redwood City

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 Redwood City

You may be interested in your other planting guides for Redwood City.