One of the best tools that you have as gardeners to help us determine 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.

By using the USDA zone info for Houston it's possible to figure out when it's the best time to plant foxglove.

Planting Calendar for Foxglove

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

Foxglove are moderately cold tolerant which means that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant foxglove in Houston 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 foxglove and expect a good harvest is probably October. You probably don't want to wait any later than that or else your foxglove may not have a chance to fully mature. You can get started a little bit earlier by starting your foxglove indoors.

Last Frost Date

The average date of last frost is February 15 in Houston. In the coldest months of winter you should expect an average low temperature of 20°F.

Just be sure to remember that USDA zone info for Houston is just an average and the actual date of last frost changes from year to year. Half of the time in Houston you get a frost after February 15 so just be sure to be ready to protect your foxglove if you have a surprise late frost.

USDA Zone Info for Houston

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 Houston

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