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.

By checking out the USDA zone info for Ellensburg it's a good idea to estimate 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.

Pennyroyal tend to make it in quite a bit of cold which means that you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant pennyroyal in Ellensburg 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. If you wait any later than that and your pennyroyal may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your pennyroyal indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Ellensburg. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Ellensburg is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Ellensburg it frosts late in the year after April 15 be ready to cover your pennyroyal if you have one of those late frosts.

USDA Zone Info for Ellensburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Ellensburg

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