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.

The USDA zone info for Royal Oak can be reviewed to determine when it's possible to plant petunias.

Planting Calendar for Petunias

Frost tolerance for petunias:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Petunias are barely cold tolerant which means that you can get them planted just a bit earlier than more sensitive plants.

The earliest that you can plant petunias in Royal Oak 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 petunias and expect a good harvest is probably August. You probably don't want to wait any later than that or else your petunias may not have a chance to really do well. If you are starting your petunias indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Royal Oak. You can expect an average low temperature of -10°F in the coldest months of winter.

Remember that USDA zone info for Royal Oak is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Royal Oak there is a last frost after April 15 be ready to protect your petunias in the event of a late frost.

USDA Zone Info for Royal Oak

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Royal Oak

You may be interested in your other planting guides for Royal Oak.