One of the best tools that you have as gardeners to help us determine 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.

You can figure out when it's a good idea to plant sunflowers in Zone 9a by reviewing the USDA zone info.

Planting Calendar for Sunflowers

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

Since sunflowers do not do well in cold weather it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant sunflowers in Zone 9a 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. Starting your sunflowers indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Zone 9a the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 20°F.

It's important to remember that USDA zone info for Zone 9a is not always accurate and the actual date of last frost is different every year. Since half of the time in Zone 9a there is a last frost after February 15 be ready to protect your sunflowers if you have a late frost.

USDA Zone Info for Zone 9a

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Zone 9a

You may be interested in your other planting guides for Zone 9a.