The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 South Houston it's a good idea to determine when it's possible to plant pennyroyal.

Planting Calendar for Pennyroyal

Frost tolerance for pennyroyal:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant pennyroyal a lot earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

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

Last Frost Date

The average date of last frost is February 15 in South Houston. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for South Houston is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in South Houston last frost occurs after February 15 be ready to cover your pennyroyal in the event of a surprise late frost.

USDA Zone Info for South 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 South Houston

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