The USDA Zone info is a great tool for gardeners to help us determine 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 a good idea to estimate when it's possible to plant pennyroyal by looking at the USDA zone info for Snohomish.

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 quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant pennyroyal in Snohomish 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 really do well. Starting your pennyroyal indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Snohomish the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 15°F.

It's important to remember that USDA zone info for Snohomish is just an average and the actual date of last frost will vary from year to year. Half of the time in Snohomish it frosts late in the year after March 15 so make sure that you are prepared to cover your pennyroyal if you have one of those late frosts.

USDA Zone Info for Snohomish

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 Snohomish

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