With the very real space constraints, urban food growing is often dismissed as a waste of time that won’t help people to become self-sufficient and won’t help the planet to feed billions of hungry mouths in the coming century.

On one level this is absolutely true: one simply can’t grow as much on an apartment balcony as in a field. That’s the maths. So, urban growing is a busted flush, isn’t it?

Not quite. First of all, you can grow a surprising amount of food in small spaces. I met a man in Bangalore who gets a year-round supply of greens from his balcony garden in that vast Indian city of 8.5 million souls. Mark Ridsdill Smith, founder of Vertical Veg tells how he grew £900 of vegetables on a London balcony in one year.

Technologies such as vertical growing and aquaponics will undoubtedly help us to grow even more in small spaces in the decades ahead.

Secondly, urban food growing assumes an incredible importance when viewed through the lens of “food empathy”.

Let me explain. The change that happens when people grow their own food, occurs on two levels. The first level is the obvious stuff – you get more exercise, fresh air, better and safer food, etc.

The second level is more subtle, perhaps a little harder to quantify – this is what we call the food empathy level. Growing your own food creates a deeper understanding of food, where it comes from, how it is produced, and the time and effort required.

Acquiring food empathy has a positive impact in unexpected places. Research has shown that food empathetic people make healthier food choices, recycle more and waste less.

When they do engage with the food chain, they make different buying decisions, buying more seasonal, local and organic food.

Seed of an idea
Take a person who has grown a butternut squash for example. Having sown a seed in spring, carefully nurtured a plant through the growing season and triumphantly harvested a squash in autumn, such a person will forever know that squashes aren't in season in February.

So, if they see them on the shelves in their supermarket in February, they know they’ve been grown on the other side of the world – and are thus probably not as nutritious as an alternative local, seasonal vegetable.

This understanding of seasonality is a powerful tool to have in your arsenal when shopping.

And that’s not all. Because they attach a real value to food and understand the effort and time involved in creating it, food growers aren’t always looking for the cheapest food (which should be good news for local food producers).

The simple act of growing some food, and acquiring food empathy, can make us happy, healthy and more sustainable.

Seismic change
At Grow It Yourself (GIY), we believe the food empathy level is where the really seismic change happens. It is at this level that we can have real impact on the food chain, human health and the health of this planet we all share.

So yes, it’s true that urban food growers will not grow all of their own food. Rural food growers probably won’t either come to think of it, with different constraints (such as lack of time) bearing down on them.

But actually it doesn’t matter how much we grow – what’s important is that we try to grow something, that we nudge ourselves just a little along a spectrum towards self-sufficiency (and away from complete reliance on the food chain).

In the GIY movement, the person who grows some herbs in a pot is just as welcome, worthwhile and valuable as the person with a 10-acre smallholding.

That dodgy looking lettuce you grew on your windowsill should be held aloft and celebrated as a symbol of your ability to change the world – one meal at a time.

So, to bring about real change in the world in terms of human health and sustainable living, we don’t have to disengage from the food chain, move to a commune, grow beards and start living off-grid.

The real potential of the home-grown food revolution is in the food empathy created by the process of food growing.

Urban food army
In that context urban food growing is not a waste of time. In fact, it's the silver bullet. Why? Because cities are where most of us will be living. There's a massive migration of people in to cities worldwide. Over the next 20 years, the global urban population will rise to approximately 5 billion.

Happily, when we talk about food empathy, it’s scale that’s important. Scale is our opportunity, for it’s quantity we need. Food-growing city dwellers the world over can become an army of food empathetic people.

Michael Kelly is founder of GIY. Food empathy and urban food growing will be discussed at the GIY Gathering on September 14th and 15th in Waterford. Speakers include Wenonah Hauter, Alys Fowler, Mark Diacono, Darina Allen, Joy Larkcom and many more. giyinternational.org