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.

In Oil City you can determine when it's possible to plant calendula by using the USDA zone info.

Planting Calendar for Calendula

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

Since calendula are moderately cold tolerant you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant calendula in Oil City 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 calendula and expect a good harvest is probably September. You probably don't want to wait any later than that or else your calendula may not have a chance to grow to maturity. If you are starting your calendula indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Oil City. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Oil City is not always accurate the actual date of last frost will vary from year to year. Half of the time in Oil City last frost occurs after April 15 so just be sure to be ready to cover your calendula if you have one of those late frosts.

USDA Zone Info for Oil City

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 Oil City

You may be interested in your other planting guides for Oil City.