One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when to plant oregano by referring to the USDA zone info for Riverdale.

Planting Calendar for Oregano

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

Since oregano do well in moderate cold you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant oregano in Riverdale 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 oregano and expect a good harvest is probably September. You probably don't want to wait any later than that or else your oregano may not have a chance to fully mature. Starting your oregano indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Riverdale the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Riverdale may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Riverdale you get a frost after April 15 so be sure to be ready to cover your oregano if you have one of those late frosts.

USDA Zone Info for Riverdale

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Riverdale

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