The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant rosemary in Altoona can be estimated by reviewing the USDA zone info.

Planting Calendar for Rosemary

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

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

The earliest that you can plant rosemary in Altoona 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 grow to maturity. Starting your rosemary indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Altoona. You can expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Altoona is just an average and the actual date of last frost is different every year. Since half of the time in Altoona last frost occurs after May 15 be ready to cover your rosemary if you have one of those late frosts.

USDA Zone Info for Altoona

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 Altoona

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