One of the first steps you take when you are figuring out 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 Sunnyvale should be reviewed to figure out when it's a good idea to plant heliotrope.

Planting Calendar for Heliotrope

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

Heliotrope require warm weather which means that you have to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant heliotrope in Sunnyvale is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant heliotrope and expect a good harvest is probably August. If you wait any later than that and your heliotrope may not have a chance to grow to maturity. If you are starting your heliotrope indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Sunnyvale the average date of last frost happens on March 15. In the coldest months of winter you can expect an average low temperature of 10°F.

It's important to remember that USDA zone info for Sunnyvale is just an average and the actual date of last frost will vary from year to year. Since half of the time in Sunnyvale it frosts late in the year after March 15 be ready to cover your heliotrope 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.