One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

One way of determining when it's the best time to plant erysimum is to examine the USDA zone info for Norman.

Planting Calendar for Erysimum

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

Erysimum do well in moderate cold which tells us that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant erysimum in Norman 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 erysimum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your erysimum may not have a chance to really do well. If you are starting your erysimum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Norman. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Norman is just an average the actual date of last frost will vary from year to year. Half of the time in Norman you get a frost after April 15 so just be sure to be ready to cover your erysimum in the event of a surprise late frost.

USDA Zone Info for Norman

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Norman

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