The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when it's a good idea to plant heliotrope is to consult the USDA zone info for Millbrae.

Planting Calendar for Heliotrope

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

You really shouldn't plant heliotrope until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant heliotrope in Millbrae 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 heliotrope and expect a good harvest is probably September. Any later than that and your heliotrope may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your heliotrope indoors.

Last Frost Date

In Millbrae the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Since the USDA zone info for Millbrae may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Millbrae you get surprised by a frost after January 31 so be sure to be ready to cover your heliotrope if you have a surprise late frost.

USDA Zone Info for Millbrae

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 Millbrae

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