Its not much but we are making do with what we have
I have slowly filled the planters with vegetables, turnips, radishes (so quick and easy to grow) Loganberries and raspberries. More planters were required and I added 2 dwarf apple trees, a cherry tree, a blueberry bush (these are great for toddlers to forage from and do so well in containers just make sure you use ericaceous soil) and a tonne of strawberry plants (I bought 2 at a local carboot and they have multiplied!). I now use the solid planters for fruit trees and bushes and use poly-bags and tubs for my seasonal veg, we are growing squash, peas, broccoli, carrots and potatoes!
I do have one patch of soil in the garden which got churned up recently when we had our own water supply put in. I have left this to grow as a wildflower patch with a bird table and the birds and the bees love it. The bees are important for pollinating my fruit trees and with such a small garden I need to offer some encouragement, it also gives the insects a nicer alternative to feed on instead of my veggies! This is my own simplified version of companion planting and I'm pleased to say the slugs have done little damage so far this year even with all this wet weather!
Organically grown food has been found to be nutritionally better for you its considerably higher in antioxidants and lower in chemicals and pesticides. This is to with the soil quality and less intensive farming. Which makes perfect sense as a large portion of what goes into growing vegetables comes from the soil. Unfortunately our concrete garden makes a compost bin very difficult so I use an alternative. I use a Bokashi bin, which is a sort of indoor anaerobic fermentation tub a bit like making home brew beer but for the garden, they are cheap, not smelly (they smell a little sour and pickled when you open the lid). You drain off the garden beer and dilute it for watering your plants and when its full dig into the garden or use it to mulch the plants. I also plant Phacelia which the bees love and when you dig it back into the garden it puts in more than it takes out and the seeds are very cheap which is where it gets its name green manure. We also have pet goldfish and the weekly water changes also go onto the garden.
I get a lot of help planting seeds with my toddler so we always get a few surprises! She also enjoys helping harvest any ripe fruit and veg and although we don't get particularly large volumes of anything we do get a little bit of lots of things. Which we use to bulk up meals and as tasty snacks.
So even if you have a small concrete garden or just a windowsill its worth growing some of your own superfood!