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

It's possible to determine when it's possible to plant pennyroyal by looking at the USDA zone info for Issaquah.

Planting Calendar for Pennyroyal

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

Pennyroyal do well in cold which tells us that you can get them planted much earlier than other plants that might not handle the cold.

The earliest that you can plant pennyroyal in Issaquah 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 little bit earlier by starting your pennyroyal indoors.

Last Frost Date

The average date of last frost is March 15 in Issaquah. In the coldest months of winter you should expect an average low temperature of 15°F.

Since the USDA zone info for Issaquah is not always accurate the actual date of last frost changes from year to year. Half of the time in Issaquah it frosts late in the year after March 15 so always be ready to protect your pennyroyal if you have a surprise late frost.

USDA Zone Info for Issaquah

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Issaquah

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