One of the first steps you take when you are getting a good idea 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.

A way of getting a good idea when to plant hollyhocks is to consult the USDA zone info for Andover.

Planting Calendar for Hollyhocks

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

Since hollyhocks are moderately cold tolerant you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant hollyhocks in Andover 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 hollyhocks and expect a good harvest is probably August. If you wait any later than that and your hollyhocks may not have a chance to fully mature. You can get started a few weeks earlier by starting your hollyhocks indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Andover and it changes from year to year. Half of the time in Andover last frost occurs after May 15 so be sure to be ready to cover your hollyhocks in the event of one of those late frosts.

USDA Zone Info for Andover

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Andover

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