One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when you can plant datura by using the USDA zone info for Alton.

Planting Calendar for Datura

Frost tolerance for datura:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant datura just a tiny bit earlier in the year because they are barely cold tolerant.

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

Last Frost Date

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

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Alton and it is different every year. Since half of the time in Alton last frost occurs after April 15 be ready to protect your datura 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.