Full sun. Once established they don't need much watering and they will self-sow a bunch! Mulch beneath plants to prevent soil slashing onto leaves and the dreaded Hollyhock Rust. Can be biennial or perennial...you just never really know. Some do bloom first year too :D

They grew great in my front yard in full sun in my yard. I saw some growing along a street in va beach and grabbed some seeds...probably a no no but they sprouted and gave me something to look at for a couple years

I longed for HH's and when I finally got a few flowering plants last year they were white and pale yellow (the mother was deep burgundy). I cut them back and now the big white one is sprouting!! Seems to be perennial so I plan to move it - replace it with one of my new doubles. As for the rust, my American neighbours gave me a solution - just work some cornmeal into the soil around the roots. Worked for me.
Northerner.