The tall spike produce blooms continuously but since buds, blooms and spent blooms are all present at one time, they are not attractive as cut flowers. Bees, wasps and various other insects pollinate hollyhocks. In mid summer the hollyhock patch is fairly buzzing with pollinators. Of course we expect that the pollinators being brought in benefit other flowers and crops.
Once you have hollyhocks, you will probably always have them. That doesn’t seem to prove them to be a perennial. The University of Illinois describes them as short-lived perennials that live as biennials. It seems true that hollyhocks usually take two years to bloom but some seem to live more than two years. It confuses more than a few people. Another issue mentioned on the web is that they easily re-seed. All of those busy pollinators account for many filled seedpods at the end of the season. The following spring the flowerbed is full of seedlings, many of which grow to maturity.
Still another issue is confusion with the similar hollyhock mallow, which is a true perennial. I am not trying to keep track of individual plants so I can’t really say how long they live. The hardiness and the generous reseeding will ensure a perennial effect after at least one year.
Besides buying seed at a nursery in the spring, you can likely get seeds from friends who grow them. You can either leave the seeds in the pods or shell them out. Be certain that they are completely dry before storing as they can mold over the winter if moisture is present.
Once you have them started in your yard, you can simply gather and redistribute seedpods to spread the color to other corners.
Where to plant them? Most varieties are over a foot tall so along a fence or in the back of a flower bed works well. During the growing season they can be used to create a low screen or yard boundary. If there are areas where you need pollinators, consider some hollyhocks to attract bees. Plant the seeds shallowly in late spring and be patient as blossoming may take two years. Then enjoy the summer color. If you find them irresistible as cut flowers, consider floating a few in a bowl of water, for a one-day display. They also dry well.
I usually cut down the dried stalks at the end of the season but this is just for appearances and does not seem to affect the return the following year. New leaves usually appear around the base of the cut off stalks along with new seedlings. If you are not enjoying hollyhocks now, consider planning for them next year and for years to come.