When to Plant Rosemary in Oskaloosa, IA

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.

You will be able to determine when you can plant rosemary by reviewing the USDA zone info for Oskaloosa.


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 more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant rosemary
Possibly ok, but a risky time to plant rosemary
Probably not a good time to plant rosemary

The earliest that you can plant rosemary in Oskaloosa 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 rosemary and expect a good harvest is probably September. If you wait any later than that and your rosemary may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your rosemary indoors.

Last Frost Date

On average the last frost is on April 15 in Oskaloosa. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Oskaloosa is not always accurate the actual date of last frost changes from year to year. Since half of the time in Oskaloosa you get surprised by a frost after April 15 be ready to protect your rosemary if you have a late frost.

USDA Zone Info for Oskaloosa

Here is the info for USDA Zone 5b.

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

Plants to Grow in Oskaloosa

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