Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of making a decision about when it's the best time to plant erysimum is to check out the USDA zone info for Zone 9a.

Planting Calendar for Erysimum

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

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

The earliest that you can plant erysimum in Zone 9a 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 erysimum and expect a good harvest is probably October. If you wait any later than that and your erysimum may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your erysimum indoors.

Last Frost Date

The average date of last frost is February 15 in Zone 9a. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Zone 9a is not always accurate the actual date of last frost is different every year. Since half of the time in Zone 9a you get surprised by a frost after February 15 be ready to cover your erysimum in the event of one of those late frosts.

USDA Zone Info for Zone 9a

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Zone 9a

You may be interested in your other planting guides for Zone 9a.