The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to determine when it's a good idea to plant scarlet pimpernels by looking at the USDA zone info for Corona.

Planting Calendar for Scarlet Pimpernels

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

You can plant scarlet pimpernels a bit earlier in the year because they are barely cold tolerant.

The earliest that you can plant scarlet pimpernels in Corona 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 scarlet pimpernels and expect a good harvest is probably September. If you wait any later than that and your scarlet pimpernels may not have a chance to fully mature. Starting your scarlet pimpernels indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Corona and it changes from year to year. Half of the time in Corona it frosts late in the year after February 15 so just be sure to be ready to protect your scarlet pimpernels 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.