One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. 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 estimating when to plant violas is to examine the USDA zone info for Oil City.

Planting Calendar for Violas

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

Violas do ok in a bit of cold which tells us that you can plant them earlier in the year than more sensitive plants.

The earliest that you can plant violas 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 violas and expect a good harvest is probably September. Any later than that and your violas may not have a chance to grow to maturity. Starting your violas indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Oil City. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Oil City and it is different every year. Since half of the time in Oil City you get a frost after April 15 be ready to cover your violas in the event of a late frost.

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.