The USDA Zone info is a great tool for gardeners to help us determine 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.

The first chance to plant erysimum in Gaithersburg should be determined by referring to the USDA zone info.

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 Gaithersburg 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 grow to maturity. You can get started a couple of weeks earlier by starting your erysimum indoors.

Last Frost Date

The average date of last frost is April 15 in Gaithersburg. You should expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Gaithersburg may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Gaithersburg you get a frost after April 15 so always be ready to protect your erysimum in the event of a surprise late frost.

USDA Zone Info for Gaithersburg

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 Gaithersburg

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