One of the first steps you take when you are estimating your gardening schedule is find your 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.

By referring to the USDA zone info for California it's a good idea to estimate when it's the best time to plant regal geranium.

Planting Calendar for Regal Geranium

Frost tolerance for regal geranium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since regal geranium do ok in moderate cold you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant regal geranium in California 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 regal geranium and expect a good harvest is probably August. Any later than that and your regal geranium may not have a chance to really do well. Starting your regal geranium indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in California. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for California is an average the actual date of last frost will vary from year to year. Since half of the time in California you get surprised by a frost after April 15 be ready to cover your regal geranium in the event of one of those late frosts.

USDA Zone Info for California

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in California

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