If you are in an urban environment you can find places to grow things like carrots and potatoes nearly everywhere. I lived near an office park a few years ago. The place was a ghost town on the weekends. I would plant potatoes, onions, carrots, and cucumbers behind their hedges or in the overgrown areas behind their parking garages. Their sprinkler systems did all the hard work for me. No one ever said a word to me about it and I know their security guards saw me.
Chives are great. They’ll grow like a weed in conditions other vegetables won’t including the shade and can add some vitamins and filler to anything you cook. They don’t need any maintenance or watering provided they’re in the ground and not a pot, and pests don’t eat them. Barely any calories in them so just let them grow in areas you aren’t otherwise using for growing calories.
All of those vary greatly with soil/sun/water/pest conditions.
The second thing to consider is that not all of those pounds produce the same amount of calories. Potatoes and beans are probably the big winners. Corn is great, but is so resource hungry and predation and pest prone so as to render them a waste of space.
Also, since potatoes grow underground, or in the container, they simply look like inedible greenery to the untrained eye. Peanuts are similar.
I have all raised beds with drip irrigation. A little work building them; but once set up, yield is increased dramatically. A plus is, VERY GOOD DRAINAGE.
EVERYONE !!! If you garden, find some Egyptian onions. Also known as Walking Onions. Just amazing. I have an ancient patch that my father started after he came home from WW2. Patch about 15 X 15 feet. You plant the sets. They grow into more or less, regular onions ( bulbs ) beneath the ground. I harvest some of the bulbs ( they do keep well ). I allow the other half to mature; and new sets appear on top of the stalks. I plant the sets. In the Spring, I have green onions ( scallions ), then later, mature onion bulbs. If you just allow them to run wild, they fall over, and the top sets will root on their own. So the term, Walking Onion. More efficient to take the time to plant the sets. About every 4 or 5 yeras, I harvest a few hundred sets, and till the patch, check the ph, etc. , etc. , then replant he sets. ------------------------------------------------------------------------------------------------------------------------------------------ [
I have 7 raised beds, about 10 X 10 each. I use ( because I am incredibly lazy ), a drip irrigation fertilzer system. Each bed is covered in heavy black plastic. Maybe 10 or 12 ( about 18 inch holes ) through the plastic in each bed. Every Spring I pull the cages and dig out each individual hole. I screen, test the ph, etc., and refill the holes. In go the plants. Then I flip a switch. That’s it. The diluted liquid fertilizer ( I only use fish emulsion ) is sucked up by a venturi & mixed with the daily watering. The raised beds prevent over watering, since they drain well. Climbing plants (cuccumbers, etc. ) are on the back edge of each bed. A 1/2 inch plastic trunk line circles the beds. I plug in a 1/8 inch feeder tube for each plant. Each tube has an emitter on the end. Watering - flow can be adjusted by simply regulating the watering time. The entire drip irrigation system cost me about $75.00; and that was about 7 or 8 years ago. I use an ORBIT watering timer. You do need a water pressure regulator, because the ORBIT system operates at 40 psi ( or less ). Occasionally, I buy an extra roll of 1/2 inch & 1/8 inch soft tubing. Maybe $20.00. ------------------------------------------------------------------------------------------------------------------------- [
