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 using the USDA zone info for Great Falls it's a good idea to figure out when it's possible to plant oregano.

Planting Calendar for Oregano

Frost tolerance for oregano:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Oregano can survive in some cold which tells us that you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant oregano in Great Falls is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant oregano and expect a good harvest is probably August. If you wait any later than that and your oregano may not have a chance to grow to maturity. Starting your oregano indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Great Falls. In the coldest months of winter you can expect an average low temperature of -30°F.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Great Falls and it will vary from year to year. Since half of the time in Great Falls you get surprised by a frost after May 15 be ready to cover your oregano if you have a late frost.

USDA Zone Info for Great Falls

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Great Falls

You may be interested in your other planting guides for Great Falls.