I wish I could come!!
I can only tell you what I would like to see from my experience at differnt greenhouses, because I've never been to a plant sale.
all plants alike together, and clearly labeled, with a desctiption and possible a picture.
that's pretty basic I guess. I've just been to lots of greehouses that do not have labels and it drives me crazy. good luck!!

I often hear from greenhouse plant suppliers that their biggest sellers are annual bedding plants like geraniums, petunias, and the sort.

succulents are a great idea. I would suggest showing different kinds in individual pots but to group them together for show.

Herbs are popular like rosemary, basil, oregano, tarragon, lavenders, parsley, etc..

To further your decorative adventure, here are some ideas which I've seen in many trade shows: using recycled materials to make bird houses (like a painted tin ceiling tile to make a roof), Old painted bannisters to make great candle holders, Birdhouse out of gourds, a wind chime made of say an old silvery tea kettle with spoons and forks hanging from below, old tin buckets to hold flowers.... you get the idea. Make mirrors out of old window panes. or use old window panes to create cold frames.

I once got a concrete ornament at an open market place (love these kinds of markets) I am using now as a fountain. It's a cement with a cupped leaf impresion in it. At the very base is a hole I use to channel water through. I use it in my pond. The people who made it are Mennonite housewives. It was cheap and it also can be used as planters for succulents.

So the idea is to build the romance and customers will come.

Whatever you choose to sell make sure you have signs with good information.

Here is a link that might be useful: The Power of Signage for Your Plant Sale

Sounds great - I wish I lived closer and I'd attend for sure! If you have pictures of the different kind of tomatoes you could put them on a sign where you display each type. I always like to know what things will look like.

Are you growing herbs? I buy those every year as many are only annuals here.

Do you make birdhouses? I'm always attracted to the different types people make. You can market them as outdoor houses for birds or as decorations indoors or out.

I've sold lots of the teacup birdfeeders but called them 'tea-lights' and put a tealight candle in each. They look great around my patio or in the garden. In the winter I used to use one in a large pot with my Dieffenbachia. You might market some of them like that as an alternative to bird feeders. While we feed the birds using a big birdfeeder I've never liked using the small teacup ones as they can get rained on and the seed goes moldy.

You might have a look at what the wholesalers are selling when you get your 'garden helpers'. They always have some interesting garden things - maybe some unusual planters or pots? Hard to advise as things sell differently depending on area and there's always something new. I sold *a lot* of wire roosters back when which can be used indoors or out. Also gardener's hand cream was a huge seller. Windchimes are also popular with gardeners and easy to make from many different items.

So much depends on your 'competition' in the way of garden centers and stores. Are there a lot of people selling prepared hanging baskets in your area? You might make a few of those to try if you are growing any appropriate plants.

Best wishes on the sale.