Florida snowbird's flower garden

I am a Northerner (Zone 5b/6a) but I live in s. Florida (Zone 10) from January until May in a large condo building. I have been given the task of planning some circular mounds of plants/flowers to beautify the grounds. Most of the other condo buildings use the same repetition of uninteresting flowers and plants, which are bought as grown plants ($$$). Since some of these mound areas are quite large (1000 sq ft), I was thinking of planting SEEDS (quite cheap, relatively) of annuals and perennials that only flower a few months up North, e.g. wave petunias, marigolds, lavender, cleome, daisies, cosmos, zinnias, impatiens, etc. I am wondering if this is feasible? How long do the flowers last? Do the annuals become perennials? Would a well-fertilized dahlia just keep on growing? I would appreciate hearing any experiences, as well as theories.

Well 1000sq ft is pretty large, If you dispersed seed, I would worry that it would have huge spots where they didn't germinate, etc. If you started the seed in some jiffy containers and transplanted to the beds that would work, but alot of work too. Black eyed susan are easy to start from seed and will reseed every year. They bloom all summer. Zinnia will get leggy, and need to be transplanted close together to look good. Marigolds are nice and bloom all summer. If I had this task...I would not waste time or money on annuals if you are going to do it every year. You can space out some beautiful perennials and it fill it nicely over time. Plumbago's, guara, gardenia radican, knockout roses, dianthus, begonia's, some lioripe grass, and pink muhly grass ( i have seen whole borders with that pink muhly grass only space about 2 ft apart). Add some colorful loropetulum bushes. Fill in large sections with bright green sweet potato vines and Lantana (lantana will grow anywhere). You could save money and get daylilies and divide them to make lots of plants and space them around too. Sounds like a tough task. Good luck.

I kinda don't recommend Lantana, 'liorupe grass' or 'sweet potato vines' (they could reseed or spread to other areas like crazy).
You could try Zinnias, Gazannias, Black-eyed susans and Scabiosa flowers, (they last for a couple years and grow well in the sun).
After Scabiosa flowers have been in the ground for a year, they grow wide and produce many many flowers. Planting seeds in the ground outdoors will be tough because the heavy rains will pound them and the soil, and the drought-season will be too hard on the tiny seedlings (unless someone is there to water them once every day or every other day until they get big enough to handle hot dry conditions).

Thanks to nickiadkins and LoveForests for your comments and thoughts. You have given me a lot to think about. But I have the whole summer to use my imagination and come up with plans!

Thanks so much!