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

In San Diego you can figure out when it's a good idea to plant heliotrope by referring to the USDA zone info.

Planting Calendar for Heliotrope

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

You should not plant heliotrope until after the last frost because they are not cold tolerant.

The earliest that you can plant heliotrope in San Diego 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 heliotrope and expect a good harvest is probably September. You probably don't want to wait any later than that or else your heliotrope may not have a chance to really do well. You can get started a few weeks earlier by starting your heliotrope indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in San Diego. In the coldest months of winter you should expect an average low temperature of 20°F.

It's important to remember that USDA zone info for San Diego is an average and the actual date of last frost is different every year. Half of the time in San Diego it frosts late in the year after February 15 so make sure that you are prepared to cover your heliotrope in the event of a surprise late frost.

USDA Zone Info for San Diego

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 San Diego

You may be interested in your other planting guides for San Diego.