Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Vallejo can be looked at to estimate when you can plant hollyhocks.

Planting Calendar for Hollyhocks

Frost tolerance for hollyhocks:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since hollyhocks do well in moderate cold you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant hollyhocks in Vallejo is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant hollyhocks and expect a good harvest is probably October. Any later than that and your hollyhocks may not have a chance to grow to maturity. Starting your hollyhocks indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Vallejo the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 25°F.

Remember that USDA zone info for Vallejo is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Vallejo last frost occurs after February 15 so always be ready to protect your hollyhocks if you have one of those late frosts.

USDA Zone Info for Vallejo

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 Vallejo

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