How much would it cost to operate a mid sized farm ?

i’m* doing

This depends on a lot of things, do you own the land or will you lease the plot? How much will this cost? Are you going to buy plant stock or plant it yourself? How much is the stock or the seed and labour? Do you have your own cultivation equipment or will you employ a contractor? Again, how much. Irrigation systems, maintenance labour, fertilizer, harvest labour and transport to market place. It shouldn’t be to difficult to work this out once you break it down.

Everything from scratch sir.

5000 square feet is a big garden in the ‘burbs, not a farm. It’s .115 acres. A decent truck or market garden that produces enough to generate income to live on should be at least 10 acres. If you read this Wikipedia entry, an general answer lies in the business section.

Tomatoes are in the family…endive…escarole…Bibb lettuce…leeks…garlic…mint…herbs…

A 5000 SF farm would actually be a large garden. That’s just over 70’ squared. (But it’s good that you specified the size, because ‘mid-size’ means different things in different parts of the US and the world. In the US Northeast, a 100-acre farm would be ‘pretty big’, but in the US Midwest a 1000-acre farm would be ‘small’.)

So you need to specify more about this mythical farm.

What is your labor market? Who will work your ‘farm’?

What kind of market do you deliver to? Roadside sales only, ‘farmer’s market’ on weekends, or delivery to other retailers? Figure your costs of serving the market in terms of labor and transportation charges.

Assuming you own the land outright, what are your costs of ownership? Property tax, liens and improvements, etc. Otherwise, you have carrying costs for the loan / mortgage for the property.

Any improvements? Do you grow on flat land, or in greenhouses? What kind of buildings do you have and maintenance costs for them?

How do you water the crop during the dry parts of the growing season, and what is your cost for water?

You can plow 10 acres with a horse or mule. Mule/plow or tractor, you will need a barn to keep said method of plowing in. You will also need the barn to store boxed produce between picking and delivery to market. You will need a vehicle to get the produce to market.
Irregation method
Hot beds/greenhouse for winter crops and starting seeds
House for seasonal laborer (10 acres requires 3 -4 people to work it during growing season.
Garden tools. Once you plant the seedlings, you need to keep weeds out.
Boxes and packaging to get produce to market
Seeds, fertilizer, insectides, growing medium for starting seedlings (tomatoes)
Land

If you’re doing it right (seed saving heirlooms, complimentary planting, permaculture polycrops, animals like ducks to eat pests and produce fertilizer, etc.), only the initial setup is potentially costly, and then little to no cost later.

There are expensive ways to do this, and cheaper ways of doing this. To read about the cheap way of doing things (in theory), check out You Can Farm by Joel Salatin. Not everyone is going to want to do it his way, but he’s straight up about what is luxury and what is necessity.

Tomatoes can only be grown in certain areas and certain times of the year(unless you live in Jamaica). 115 acres is a lot of earth to work. are you sure tomatoes are your crop of choice? many variables are possible with any type of farm and its requirements. planting the tomatoe plants, watering the plants and harvesting the tomatoes is a job that requires additional help, other than yourself. with the unknowns here, it’s almost impossible to give you a money figure.