You could try Winter Sowing. It is conceptually very easy and I shouldn't think it's too late in your zone. But the people on the WS Forum can certainly tell you.

Here is a link that might be useful: Winter Sowing Hollyhocks

Hollyhocks are a confusing plant, at least to me. It seems if you research them some are annuals, some biennials and some perennials. All of the ones I have ever grown have been biennials, even seed from people that claim they are annuals or perennials (more often). I have ordered some seed that is supposedly supposed to bloom first year and is an annual and some that may bloom the first year and is considered a perennial, so time will tell.

So whether or not you will get flowers this year is unknown, I have never gotten blooms the first year even from seed started indoors. You have a longer growing season so that might help.

I have not found that the seeds need any type of stratification or cold treatment so you could plant them as soon as you can work the soil and let nature do the rest, you could winter sow as suggested or you could start them indoors to give them a jump start. IF you have a so called variety that will bloom the first year starting them 6-8 weeks before last frost will have them bloom earlier.

SCG