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.

The first chance to plant sunflowers in Alameda should be determined by referring to the USDA zone info.

Planting Calendar for Sunflowers

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

Sunflowers do not do well in cold weather which tells us that it's necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant sunflowers in Alameda is February. However, you really should wait until March 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. Any later than that and your sunflowers may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your sunflowers indoors.

Last Frost Date

The average date of last frost is January 31 in Alameda. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Alameda may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Alameda you get surprised by a frost after January 31 so make sure that you are prepared to cover your sunflowers if you have a late frost.

USDA Zone Info for Alameda

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Alameda

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