One of the first steps you take when you are getting a good idea your gardening schedule is find your 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.

It's possible to determine when it's possible to plant pennyroyal by checking out the USDA zone info for Humboldt.

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 do well in cold.

The earliest that you can plant pennyroyal in Humboldt 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. Any later than that and your pennyroyal may not have a chance to grow to maturity. Starting your pennyroyal indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Humboldt. You can expect an average low temperature of 0°F in the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Humboldt and it is different every year. Since half of the time in Humboldt there is a last frost after April 15 be ready to cover your pennyroyal if you have a surprise late frost.

USDA Zone Info for Humboldt

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 Humboldt

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