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

You can determine when you can plant pennyroyal in Walnut by referring to the USDA zone info.

Planting Calendar for Pennyroyal

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

Pennyroyal can survive in a bit of cold which means that you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pennyroyal in Walnut 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. If you are starting your pennyroyal indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Walnut. In the coldest months of winter you can expect an average low temperature of 30°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Walnut and it changes from year to year. Half of the time in Walnut it frosts late in the year after January 31 so be sure to be ready to cover your pennyroyal in the event of one of those late frosts.

USDA Zone Info for Walnut

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Walnut

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