One of the first steps you take when you are estimating 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.

A common way of determining when it's the best time to plant sunflowers is to use the USDA zone info for Red Bluff.

Planting Calendar for Sunflowers

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

You should not plant sunflowers until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant sunflowers in Red Bluff 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 really do well. If you are starting your sunflowers indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Red Bluff the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Remember that USDA zone info for Red Bluff is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Red Bluff you get a frost after February 15 be ready to protect your sunflowers if you have a surprise late frost.

USDA Zone Info for Red Bluff

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 Red Bluff

You may be interested in your other planting guides for Red Bluff.