One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Smithfield should be used to figure out when it's a good idea to plant datura.

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.

Since datura are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant datura in Smithfield 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. If you wait any later than that and your datura may not have a chance to fully mature. You can get started a few weeks earlier by starting your datura indoors.

Last Frost Date

In Smithfield the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Smithfield and it changes from year to year. Half of the time in Smithfield there is a last frost after April 15 so make sure that you are prepared to cover your datura if you have a late frost.

USDA Zone Info for Smithfield

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 Smithfield

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