One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Healdsburg you can determine when it's the best time to plant catharanthus by checking out the USDA zone info.

Planting Calendar for Catharanthus

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

Since catharanthus do not do well in cold weather you need to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant catharanthus in Healdsburg 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 catharanthus and expect a good harvest is probably September. You probably don't want to wait any later than that or else your catharanthus may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your catharanthus indoors.

Last Frost Date

In Healdsburg the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Healdsburg is an average and the actual date of last frost changes from year to year. Since half of the time in Healdsburg there is a last frost after February 15 be ready to protect your catharanthus if you have a surprise late frost.

USDA Zone Info for Healdsburg

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Healdsburg

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