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.

You should be able to determine when it's a good idea to plant diascia by referring to the USDA zone info for National 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 get them planted earlier than more sensitive plants.

The earliest that you can plant diascia in National 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 fully mature. You can get started a little bit earlier by starting your diascia indoors.

Last Frost Date

The average date of last frost is January 31 in National City. In the coldest months of winter you can expect an average low temperature of 35°F.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for National City and it changes from year to year. Since half of the time in National City last frost occurs after January 31 be ready to protect your diascia in the event of a late frost.

USDA Zone Info for National City

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in National City

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