When to Plant Rosemary in Norristown, PA

One of the best tools that you have as gardeners to help us figure out 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.

In Norristown you can estimate when you can plant rosemary by referring to 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.

You can plant rosemary quite a bit earlier in the year because they are very cold tolerant.

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 Norristown 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. Any later than that and your rosemary may not have a chance to grow to maturity. If you are starting your rosemary indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Norristown the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of 0°F.

It's important to remember that USDA zone info for Norristown is just an average and the actual date of last frost changes from year to year. Since half of the time in Norristown there is a last frost after April 15 be ready to protect your rosemary if you have a late frost.

USDA Zone Info for Norristown

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low0°F
Highest Expected Low5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Norristown

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