One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

The best time to plant larkspur in Sunnyvale should be estimated by using the USDA zone info.

Planting Calendar for Larkspur

Frost tolerance for larkspur:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Larkspur do well in cold weather which means that you can plant them a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant larkspur in Sunnyvale 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 larkspur and expect a good harvest is probably September. If you wait any later than that and your larkspur may not have a chance to fully mature. If you are starting your larkspur indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Sunnyvale. It might get as low as 10°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Sunnyvale and it will vary from year to year. Since half of the time in Sunnyvale you get surprised by a frost after March 15 be ready to protect your larkspur if you have a surprise late frost.

USDA Zone Info for Sunnyvale

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Sunnyvale

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