One of the first steps you take when you are making a decision about 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.

The USDA zone info for Prosser can be used to figure out when it's the best time to plant common hollyhock.

Planting Calendar for Common hollyhock

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

Common hollyhock do ok in mild cold which means that you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant common hollyhock in Prosser 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 common hollyhock and expect a good harvest is probably September. Any later than that and your common hollyhock may not have a chance to really do well. You can get started a couple of weeks earlier by starting your common hollyhock indoors.

Last Frost Date

The average date of last frost is April 15 in Prosser. In the coldest months of winter you can expect an average low temperature of 0°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Prosser and it is different every year. Since half of the time in Prosser you get surprised by a frost after April 15 be ready to cover your common hollyhock if you have one of those late frosts.

USDA Zone Info for Prosser

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Prosser

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