Fun With Arithmetic

I really should get out more.
I take a statistic or measurement and extrapolate data using What If thought experiments.  It's not an Obsessive-Compulsive thing, and I don't do it all the time, just now and then.  From time to time I get right into it, meandering from one thought to another, with the end result having nothing to do whatsoever with what I started from.

Take a simple figure:
According to the USDA, a typical human in the US consumes 5 pounds of food per day.  I don't have the breakdown on that, but for 2000 calories it works out to around 400 calories per pound so there must be some meat, sugar, oil and grains in there.  Vegetables come in around 100-200 calories/pound.  Starchy foods, potato for example, will tend to be higher.  Let's say 20% of that 5 pounds is from vegetables.  That's a pound per person per day.  The US population is 317 Million humans.  At 1 pound per person per day, rounding it down to make it easy on me, I come up with a figure of 300 million pounds of vegetables per day.  Over the course of a year, 109,500,000,000 (109 Billion) pounds of vegetables would be consumed.
That's a lot of vegetables.

Let's give it a price.
Apples around here go for 1.39/pound in the supermarket.  Fresh green beans go for $2.29/# in season.  Hothouse tomatoes will fetch anywhere from 99¢/pound to $2.99/pound.  Canned peas are 59¢ for a 15 ounce can and there is easily 4 ounces of water in there.  Fresh Certified Organic arugula will bring $9/pound. NINE BUCKS A POUND!  Prices are all over the place depending on location, month, producer, how its packaged, what's in it or not in it.  I operated a Pick Your Own operation and easily sold everything for a flat rate $1.50/pound, 4 years ago.  I'll use that number: 109 billion pounds at $1.50/pound = $164,250,000,000/yr.  I'll settle for half that in cash.

I've got a little under 4 acres.  I won't be making much of a dent in that 109 billion pounds.  But I can grow some of it, even sell some of it.  At a pound per day per person, $1.50/pound, 7 days/week, a typical farm customer would make good use of 7 pounds per week, or $10.50/week per person.  Around here the average houshold has 2.7 people.  I'm not sure what was done with the other .3 people. At 2 people to a household, a customer buying for that household would spend around 20 bucks/week for fresh produce.  At 3 people to a houshold, $30/week.  These are numbers I can deal with.

To cover my bills, allow for some savings and investment, 20-30 customers per week spending $20-$30 per week would get me by just fine.  20x$20=$400.  30x$30=$900.  $400-$900/week?  Yeah, I can get by on that just fine.  20-30 people would not require me to be available 24/7.  I could move the product on weekends.  10-15 customers coming through the gate on each weekend day is hardly going to run me ragged.  I can keep my regular job for a while, pay off the land, put together some savings, build that barn I want, even get a girlfriend for Bull.  In all honesty, half of the lower range would be enough to give me a serious boost.

How much space would I need, doing things the way I do things, to produce the crops needed to service this customer volume?  I build my standard growing beds with dimensions of 4'x50' =200 square feet.  I plant intensively so that hard worked area is put to good use.  I start many species in the greenhouse so they can be transplanted as soon as space is available.  I grow a variety of plants to offer a fine selection to customers, so coming up with accurate numbers gets tricky.  Spinach takes up little space, grows quickly, but puts out a small weight.  Cabbage takes a little more space, takes more time, puts out a big fat head, but would typically command a lower price per pound.  Tomatoes take forever, tend to spread out, can put out a good pile of fruit, and gets a strong price with good customer demand.  Radish is tight, fast, and cheap.  

Years ago I came up with some fairly reliable figures for average planting density and production.  4 plants per square foot is a reasonable average density.  1/4 pound of marketable product per plant is a reasonable production estimate.  90 days is a fair time period for an average crop.  $1.50/pound is a fair price for a customer to pay for the freshest produce possible, especially if they do the picking.  Putting all this together:
Area:    200 sqft
Plants:    4/sqft
Yield:    .25#/plant
Price:    $1.50/#
Time:    90 days
Multiply all this together I come up with 1 bed being able to produce 200 pounds of produce in 90 days, with a value of $300.  Since I can grow crops all year in zone 8b, each bed has the potential to produce $1200/year =$100/month =$6/sqft/yr = 12¢/sqft/week.  If I need to produce $400/week, I need 3333 sqft, = 17 beds.

The math here does not take problems into account.  Not everything grown will be marketable.  Cutworms knock down seedlings, leaf miners ruin the greens, an early frost knocks out the peppers, the chickens gobbled up ALL the lettuce.  There are more ways to lose crops than I can list.  To account for problems, add a percent marketable coefficient to the equation:
Area x Planting Density x Average Yield x Price x Marketable Portion = Crop Value
200 x 4 x .25 x 1.5 x .5 = $150 per bed in 90 days, with half of the product being unmarketable.

Now I've got a reasonable figure to work with.  Experience has shown that using my methods and crop selection, these figures are right on.  They tell me 35 beds is what I need to be able generate enough income to cover my bills, flush the job, and make a good living doing what I want to do.  That price is rather low.  I'm not growing supermarket commodity quality vegetables.  These are heirloom cultivars, as fresh as the morning dew, grown without chemicals in a manner consistent with Certified Organic.  Premium Quality commands a premium price. 

At $2/pound, 20 beds in my location would produce enough to match minimum wage.  That's 4000 square feet.  Adding space for the pathways between the beds, 6000 sqft would be sufficient to equal minimum wage, and that's with half the product thrown out.  20 beds would not require full time effort.  There's more to life than earning minimum wage.   In my estimation, a healthy human adult working full time should be able to handle 50-100 beds.  Putting in farmers hours, improving efficiency with tools and equipment, more beds can be handled.  With a team of a handful of people dividing the labor, many beds per person can be maintained.  2-4 beds per person per day, with a 90 day cycle puts an acre per person into the reasonable category.

The above equation is about as simple as it gets.  I have a spreadsheet with numbers and formulas all over it.  Lots of columns for different sizes of planted area.  In an acre, with ample pathways between the beds, 125 beds/acre will fit.  That's 25000 square feet of growing space per acre.  I've got 3+ acres to work with.  Plugging these numbers into the equation produces some pretty significant figures.  You hear claims of $50,000 per year being possible on an acre of land. 

These claims are believable.

What if something could be done with the unmarketable produce?
Often the only reason a tomato is not marketable is due to a blemish or maybe a big knot sticking out one side.  Misshaped squash is still edible.  Peel an onion, end up with an onion.  This side of the garlic is no good, but the other side is just fine.  Lettuce is tough-can't can/cook/freeze/preserve it.  Except for the lettuce, I can find lots of use for this stuff as an ingredient.   I can get $2-4/pound for all natural tomatoes.  I can get $6-12 per pint for all natural tomato sauce.  I find it intersting that 2nd rate product can garner twice the price.

Area x Planting Density x Average Yield = Total Product
200 x 4 x .25 = 200 pounds per bed per cycle.
If my Marketable Portion is 50%, my unmarketable portion is 50%.  So, 100 pounds marketable, 100 pounds unmarketable.  If a person can handle a bed per day, the math says 100 pounds per day to work with.  Some of it will be recoverable, some won't.

If it can't be recovered for human consumption, the product will surely serve the livestock.  Chickens will eat the dickens out of that lettuce.  Pigs are without vanity and don't care what it looks like as long as it smells good.  Worms are less demanding, eating whatever you toss at them.  Earthworm castings sell for $600/ton =30¢/pound x 100 pounds per day = $10k/year.  Half of that would just about pay my mortgage.  If all you could do was compost 100 pounds per day, it sure would be a boost to your soil fertility.

For the recoverable portion, there is work to do: harvest, sort, cut, peel, wash, and come up with a plan to put it to use.  A licensed kitchen to process the produce into Value Added goods is a natural extension of a vegetable farm.  Canning is pretty easy to figure out.  Assuming you can use the existing structure, systems, and appliances, the equipment needed is simple.  A functioning operation can be set up for a few hundred bucks, including a license.  A decent canner will hold 9 quarts = 18 pounds.  That's a good chunk of what is probably available.  If you are operating a few beds, a fridge will hold that produce until you have a batch.  If you are running many beds, you can probably put together a full canner load every day or two or a couple of loads every day.  Instead of green beans in season, you have green beans anytime of the year.  Instead of just fresh okra, you've got pickled okra.  This is important, because if you've grown okra you know full well the need for a means of putting it to use.  Just about everything can be canned, pickled or fermented.  The chickens still get the leafy greens and you'll still have scraps for the livestock.

Taking things one step further, make something from the produce.  Instead of canned tomatoes, make tomato juice, sauce, paste, or sun dried tomatoes packed in olive oil.  Instead of carrots, carrot juice.  Instead of pickled peppers, whip up a batch of hot sauce, Baby.  The variety and distinctiveness of products which can be produced can turn a vegetable farm into an artisan food kitchen:  Roasted smoked red pepper sauce, opal basil pesto with creole garlic, golden cherry tomato marinara...of course the desire to cook would need to be part of the farmer's dream, or at least the ability to hire a cook. 

What if this specialty product line were in demand to such an extent that selling fresh produce for $2/pound is a waste of resources that would better serve the kitchen to create a product valued at $10/pound?  Two things are clear: 1-The results of the equation above change considerably.  2-I've wandered too far from my orginal thought.

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