Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Alton you will be able to figure out when it's a good idea to plant achimenes.

Planting Calendar for Achimenes

Frost tolerance for achimenes:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since achimenes do not do well in cold weather you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant achimenes 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 achimenes and expect a good harvest is probably August. You probably don't want to wait any later than that or else your achimenes may not have a chance to really do well. You can get started a little bit earlier by starting your achimenes indoors.

Last Frost Date

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

Remember that USDA zone info for Alton is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Alton you get surprised by a frost after April 15 so make sure that you are ready to protect your achimenes in the event of a 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.