When to Plant Pennyroyal in Grimes, IA

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when to plant pennyroyal in Grimes 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.

Since pennyroyal are one of those plants that can tolerate quite a bit of cold weather you can plant them a lot earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant pennyroyal
Possibly ok, but a risky time to plant pennyroyal
Probably not a good time to plant pennyroyal

The earliest that you can plant pennyroyal in Grimes 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 grow to maturity. If you are starting your pennyroyal indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Grimes. It might get as low as -20°F during the coldest months of winter.

It's important to remember that USDA zone info for Grimes is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Grimes there is a last frost after April 15 be ready to protect your pennyroyal in the event of a surprise late frost.

USDA Zone Info for Grimes

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°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 -15°F.

Plants to Grow in Grimes

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