I have hollyhocks growing alongside my house between the house and driveway. My neighbor says that the roots will wreck the foundation and water will get in the basement, is this true? I just love them growing next to the house and don’t want to pull them up if I don’t have to.
There is some truth to what your neighbor said, but hollyhocks are generally biennial (lives only two years). Sometimes hollyhocks will live longer than that and get large enough to do some damage to your sidewalk of driveway, but that would only be because where you have them planted isn't a large enough space for their roots to grow properly. If you have single-flowered (one row of petals like a daisy) hollyhocks, you might also run into a problem of them being a little too prolific. If you keep the plants in check (removing extra hollyhock plants and cutting back flowers and stems immediately after their flowers fade) you shouldn't have too many problems in a mostly concrete space like a driveway. Many well-tended English gardens have hollyhocks growing right up against the house without problems.