One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 Smithfield should be used to estimate when it's a good idea to plant alternaria.

Planting Calendar for Alternaria

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

Since alternaria do not do well in cold weather you must wait until after the last frost before you can plant them.

The earliest that you can plant alternaria in Smithfield 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 alternaria and expect a good harvest is probably August. Any later than that and your alternaria may not have a chance to grow to maturity. If you are starting your alternaria indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Smithfield the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 10°F.

It's important to remember that USDA zone info for Smithfield is just an average and the actual date of last frost changes from year to year. Half of the time in Smithfield you get surprised by a frost after March 15 so just be sure to be ready to cover your alternaria if you have a surprise late frost.

USDA Zone Info for Smithfield

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Smithfield

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