How do plant hollyhock bulbs? Do you lay them flat?
Hollyhocks have roots (but they don't have bulbs). Just place the roots with the root tips down and the stem ends up, in a hole that is deep enough so that the base of the stems will be at the surrounding ground level when you fill in the planting hole.
Altagardener is right, there is no bulbs but what you have is a rooted plant that at this time of year needs to be plants as instructed by altagardener.
I would also add some compost to the planting hole and a handful of Blood / fish / bone Meal to the soil removed for the hole, as you replace the soil, make sure the plant is only as deep as the plant was before.
It will be good idea to place a cane or other stake into this soil as these plants can reach 6 feet tall and if they are not staked the breeze will rock them about and loosen the roots it break the plant at their stems.
These plants can suffer from Grey mold or a rust that forms on the foliage but it does not kill the plants, the best way to TRY to avoid this is to make sure the plants are in a spot where there is good air flow, never water the plants when it is already humid as the stillness allows the moisture to stay on the plants, best time to water (the soil NOT the foliage) is mid morning or early evening as this allows time for the plant to dry off., healthy plants can fight off diseases like mold but some have it even with the best will in the world.
You may not get a huge spray of flowers this year however, next year it should be good, IF you love in a clod area (sorry I don't know your zone) it would be best to give the plant a few inches of leaf mold or some form of blanket to protect them, I always cut my Hollyhocks down to about 3-4 inches jest before the real frost / freeze comes by then most of the foliage will have turned brown and winter will cause the plant to freeze to the underground roots. Come early spring after frost has gone, use you hand to thin out gently the the mulch so the warmer sun can help rejuvenate the plant for flowering again.
Warning : these are classed as short lived perennials so, after maybe 3-4 years they will be small flowers if any but, each spring scrape away some soil at the base in spring and you should see some new shoots growing, just use sharp knife and cut them away WITH a part of the roots attached and replant in a small pot till large enough to plant in the garden.
Hope this helps you a bit. Good luck, WeeNel.