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.

You can estimate when it's possible to plant sunflowers in Larkspur by looking at the USDA zone info.

Planting Calendar for Sunflowers

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

Since sunflowers are not cold tolerant it's necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant sunflowers in Larkspur 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 grow to maturity. You can get started a couple of weeks earlier by starting your sunflowers indoors.

Last Frost Date

The average date of last frost is February 15 in Larkspur. In the coldest months of winter you can expect an average low temperature of 25°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Larkspur and it is different every year. Since half of the time in Larkspur you get a frost after February 15 be ready to cover your sunflowers if you have a surprise late frost.

USDA Zone Info for Larkspur

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 Larkspur

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