When to Plant Petunias in Monticello, IL

One of the first steps you take when you are figuring out 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 Monticello should be read to figure out when you can 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.

You can plant petunias a bit earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

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 Monticello 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 really do well. If you are starting your petunias 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 Monticello. You should expect an average low temperature of -15°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Monticello and it can change quite a bit from year to year. Half of the time in Monticello you get surprised by a frost after April 15 so always be ready to protect your petunias if you have one of those late frosts.

USDA Zone Info for Monticello

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 Monticello

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