Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of determining when it's possible to plant sunflowers is to refer to the USDA zone info for Smithville.

Planting Calendar for Sunflowers

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

You really shouldn't plant sunflowers until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant sunflowers in Smithville 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 sunflowers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sunflowers may not have a chance to really do well. If you are starting your sunflowers indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on March 15 in Smithville. In the coldest months of winter you can expect an average low temperature of 15°F.

Always keep in mind that USDA zone info for Smithville is an average and the actual date of last frost will vary from year to year. Since half of the time in Smithville you get surprised by a frost after March 15 be ready to protect your sunflowers in the event of a surprise late frost.

USDA Zone Info for Smithville

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Smithville

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