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 Corona can be reviewed to estimate when to plant twinspur.

Planting Calendar for Twinspur

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

You can plant twinspur a little bit earlier in the year because they do well in moderate cold.

The earliest that you can plant twinspur in Corona 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 twinspur and expect a good harvest is probably October. If you wait any later than that and your twinspur may not have a chance to really do well. If you are starting your twinspur indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Corona the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Corona is just an average the actual date of last frost is different every year. Since half of the time in Corona you get a frost after February 15 be ready to cover your twinspur if you have a late frost.

USDA Zone Info for Corona

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 Low	25°F
Highest Expected Low	30°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 Corona

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