One of the first steps you take when you are figuring out your gardening schedule is find your 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.

In Stockton you can estimate when it's the best time to plant sunflowers by checking out 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 are not cold tolerant you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant sunflowers in Stockton 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. If you wait any later than that and your sunflowers may not have a chance to fully mature. You can get started a little bit earlier by starting your sunflowers indoors.

Last Frost Date

In Stockton the average date of last frost happens on February 15. You should expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Stockton is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Stockton you get surprised by a frost after February 15 so make sure that you are ready to cover your sunflowers in the event of one of those late frosts.

USDA Zone Info for Stockton

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 Stockton

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