When to Plant Petunias in Grimes, IA

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant petunias in Grimes should be estimated by referring to the USDA zone info.


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.

You can plant petunias slightly earlier in the year because they are barely cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant petunias
Possibly ok, but a risky time to plant petunias
Probably not a good time to plant petunias

The earliest that you can plant petunias in Grimes 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. If you wait any later than that and your petunias may not have a chance to fully mature. You can get started a little bit earlier by starting your petunias indoors.

Last Frost Date

The average date of last frost is April 15 in Grimes. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Grimes is an average the actual date of last frost changes from year to year. Since half of the time in Grimes you get surprised by a frost after April 15 be ready to protect your petunias if you have a late frost.

USDA Zone Info for Grimes

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Grimes

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