When to Plant Begonias in Alton, 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.

You can estimate when it's the best time to plant begonias in Alton by referring to the USDA zone info.


Planting Calendar for Begonias

Frost tolerance for begonias: Not tolerant of frost.
When to plant: After the last frost.

Since begonias are not cold tolerant you have to wait until after the last frost when the weather gets warmer before you can plant them.

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

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

Last Frost Date

On average the last frost is on April 15 in Alton. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Alton is an average the actual date of last frost changes from year to year. Half of the time in Alton last frost occurs after April 15 so just be sure to be ready to cover your begonias in the event of a surprise late frost.

USDA Zone Info for Alton

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 Alton

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