One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Downingtown you will be able to estimate when it's a good idea to plant erysimum.

Planting Calendar for Erysimum

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

Erysimum are moderately cold tolerant which tells us that you can get them planted earlier than more sensitive plants.

The earliest that you can plant erysimum in Downingtown 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. Any later than that and your erysimum may not have a chance to grow to maturity. You can get started a little bit earlier by starting your erysimum indoors.

Last Frost Date

In Downingtown the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Downingtown and it is different every year. Half of the time in Downingtown you get a frost after April 15 so be sure to be ready to cover your erysimum if you have a surprise late frost.

USDA Zone Info for Downingtown

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Downingtown

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