Tall Flowers

Hello, can anyone advise on plants that produce tall flowers?

Ideally they should be able to be sown this year and grow to around 3-4ft high in a 6 inch deep south facing trough. 

Would delphinium, lupin or knipofium be a candidate?

Thanks

Some varieties of cosmos get pretty tall.

Agastache, nicotiana (s/p?), some zinnias, some daisy varieties,  rudbeckia and coneflowers as well, but if you're starting from seed you won't get flowers until its second year.

Thanks for all your replies - it's shown that I'm in-experienced when it comes to flowering plants, and didn't know most don't flower first season planted 

I've bought a pack seeds for Delphinium Giants which I'll sow this year ready for next and look into the others suggested. I fancy Knipofium (poker) after seeing them on Gardenener's World last week.

Cheers

I'm growing hollyhocks for the first time this year, they can be spetacular.
I've got about 30 seeds that have germinated, I'm not expecting to get anything from them this year.

Has anyone grown hollyhocks in large pots?

Br