One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Inverness should be reviewed to estimate when it's possible to plant sunflowers.

Planting Calendar for Sunflowers

Frost tolerance for sunflowers:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Sunflowers require warm weather which tells us that you really should wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant sunflowers in Inverness 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. Starting your sunflowers indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Inverness. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Inverness is just an average the actual date of last frost will vary from year to year. Since half of the time in Inverness you get a frost after February 15 be ready to protect your sunflowers in the event of a late frost.

USDA Zone Info for Inverness

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 Inverness

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