The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Irving should be read to figure out when 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 much earlier in the year because they do well in cold.

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

Last Frost Date

In Irving the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

Keep in mind that USDA zone info for Irving is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Irving you get surprised by a frost after March 15 be ready to cover your pennyroyal in the event of one of those late frosts.

USDA Zone Info for Irving

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Irving

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