One of the first steps you take when you are determining your gardening schedule is find your 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.

The USDA zone info for Opp can be looked at to estimate when it's a good idea to plant zinnia.

Planting Calendar for Zinnia

Frost tolerance for zinnia:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since zinnia do not do well in cold weather it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant zinnia in Opp is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant zinnia and expect a good harvest is probably August. If you wait any later than that and your zinnia may not have a chance to grow to maturity. If you are starting your zinnia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Opp the average date of last frost happens on March 15. You can expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Opp is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Opp last frost occurs after March 15 be ready to cover your zinnia in the event of a late frost.

USDA Zone Info for Opp

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Opp

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