Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of determining when to plant rosemary is to examine the USDA zone info for Vail.

Planting Calendar for Rosemary

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

Rosemary are one of those plants that can tolerate quite a bit of cold weather which tells us that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant rosemary in Vail 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 rosemary and expect a good harvest is probably August. Any later than that and your rosemary may not have a chance to fully mature. If you are starting your rosemary indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Vail. It might get as low as -25°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Vail and it will vary from year to year. Half of the time in Vail you get a frost after May 15 so make sure that you are ready to cover your rosemary if you have a late frost.

USDA Zone Info for Vail

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Vail

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