The lowest tech way of figuring out what to grow is trial and error but this can take several decades. A faster way is to ask seasoned growers what sells best and observe what is selling well at your market.

one bit of advice, never grow anything you won't eat yourself.

In SW Ohio the big sellers are green beans, sweet corn, beets, scallions, carrots, any fruit, tomatoes, tomatoes, tomatoes, peppers (sweet, not hot), butternut squash, onions, cabbage, lettuce, peas.

With a large well run home garden it is easy to come up with extra produce to sell at a nearby farmers market. Making a ton of money doing it may not be all that easy. Different people shop at farmers markets for different reasons. You'll learn more by participating in the market and seeing for yourself what people want and how much they want to pay for it.

There are the garden classics that everyone buys (tomatoes, green beans, squash, corn, bell peppers, berries) which you really need to have at your stall. But you also need something eye-catching to draw shoppers into your space, which could something like cut flowers, a colorful display of peppers (people love seeing hot peppers at the market but rarely buy a ton of them), extra large or freakishly shaped squash or pumpkins or even some sort of tropical fruit that no one else sells. The main thing is to be involved and let everyone shopping there know that YOU are the gardener and you know about these crops. People really respect knowlege and experience.

But all that being said, you really can't cut to the front of the line. Everyone has to take the baby steps and see what works for them. Advice that works for one person won't work for everyone. You'll have to try it and see what you can do to make money with it

IMO you have to have what everyone else has, tomatoes, green beans, potatoes, squash, cucumbers and corn (if you have the room). I don't do corn, it is resource intense and you have one shot to pick and sell it.

Once you have these crops, then branch out into different varieties. I have 12 kinds of squash and 12 kinds of cucumbers. I sell the green zucchini and plane green cucs the most, but the other stuff get people to stop at your stall.

Also give away free samples. If it is good, then they will buy it. I would guess 75% of the time I give them a sample, the person will buy. Then the other 25%, some will buy the next week.

They best thing to do is go to the market and check things out. Ask questions and really get to know your produce. I agree with the person who said grow what you will eat.

Good Luck!

thanks to everyone for your great advice! Only growing what I eat makes sense, in case I need to literally eat my lack of profits. In addition to the standbys ~tomatoes, green beans, squash, and bell peppers~ I do have raspberries, figs and apples, and have been thinking of planting a flower patch from which I could make bouquets. I think samples are a GREAT idea I have also thought of growing bird house gourds and making bird houses. This year will doubtless just be a trial run with whatever surplus I have, which will let me see what works; the only seasoned growers I know run CSAs, which is rather a different sort of thing.

thanks again, all!
Kyrstin

My 'trial run' was last year. It was fun and certainly a learning experience.
My advice would be to grow what you know the best. The passion/experience translates into enthusiasm. I sell perennials until the dahlias and other cut flowers come into season. Then it's crazy busy.
We have one vendor at our market who basically sells three things, each in their own time. First he sells asparagus, then strawberries, and finally sweet corn --he sells out in just a few hours.
Marketing is a large part of selling, perhaps it would be useful to think about your displays, signs, etc.
Research your market by visiting the market and watching what goes on, who sells what and how are their goods displayed. As much as we all diss the big box stores, they know how to move the merchandise.

you all are all, so nice,400sq.feet?I have 800 in my first planting of tomatoes. That is only two 4'wide strips by 50'long, for 400sqf.
You must know how much you need to make in order for you to go into such a venture.Then you must know something about what your clients want not what you like.You must know how much you can expect from each plant in perfect conditions,etc.
But if you just want to play at it go have fun, but it is a buss. to be taken serious as any other buss. venture out there.

As a market manager, I can tell you that out here both the big growers and the "home garden" growers do just as well.Some people feel more comfortable buying from the little guy, while others feel that only the big growers have anything worth buying. I find that being a consistent vendor is equally as important. If you only show up to sell once in a while, when you have surplus from your garden, customers don't seem to buy from you. I have big vendors that only show up once in a while, and guess what...they don't sell as well as the vendors that show up regularly. Whatever you do decide to sell, make sure it is high quality and don't sell yourself cheap.

Heidi

By far the most profitable person in our market is the flower lady. She sells flowers for all amounts and is over run with business. you can grow alot of flowers in a small space. I grow and sell peaches and they are profitable however it takes four years to get your first crop

I am a small grower who has been doing farmers market for a few years. Grow what you love and your enthusiasm for your product will help you in your marketing efforts. I am always trying to find something a little different than what everyone else is selling. For example, even tho' I grow tomatoes for personal use and may take surplus to market -- I don't grow tomatoes for market because there are too many others selling tomatoes. Breaking in to a new market means you have to build your relationship with customers and develop your clientele. A lot of regulars always bought from the vendors who have been there the longest, you have to find your niche, and that can take years, but is also based on what your interests are. I am studying herbalism and I often talk to customers about nutrition. I am slowly developing a clientle who knows that I grow organically [can't really advertise that since I am not certified], and are looking for the health angle. For example, I will grow something like a "Health Kick" tomato as opposed to a run of the mill variety so I can tell people it has 20% more lycopene than regular tomatoes. Marketing and educating your consumers is one way to build your clientele, [someone mentioned samples too etc].
Since I am a small home grower and not a large commercial grower, I mostly grow what I will use myself and sell my surplus. some exceptions are radishes which I don't care for, but usually sell pretty well. I try to experiment with something different every year but I know if I grow too much of what I won't use personally, I will end up with too much waste.
You have to determine how much time and work you want to put into it. I need to find ways to maximize productivity without increasing the amount of time and work I have to put into it. I work hard all season and have little time for anything else. By blueberry harvest time, I usually start losing the war on weeds everywhere else.