Before planting it is a good idea to find your USDA Zone info to figure out 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.

A way of figuring out when it's the best time to plant sunflowers is to use the USDA zone info for Donna.

Planting Calendar for Sunflowers

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

It's probably not a good idea to plant sunflowers until after the last frost when the weather gets warmer because they do not do well in cold weather.

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

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Donna. You can expect an average low temperature of 25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Donna may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Donna last frost occurs after February 15 be ready to cover your sunflowers in the event of one of those late frosts.

USDA Zone Info for Donna

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Donna

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