How often do you consider the miles your food travelled to reach your plate?

In a climate of growing food concerns, Sarah Bentley argues this is a question we should ask ourselves more often. And it's something she tackles through Growing Communities, an organic veg-box scheme that collaborates with local, small-scale farmers and the community kitchen Made in Hackney.

Ahead of Sarah's urban food growing talk at Stories, Broadway Market, next Tuesday 23rd September, we asked her what difference growing city greens can really make.

You champion salad as the best crop to grow in a city. Why is that?

Once you harvest carrots or potatoes, that's it; they're gone. But salad crops can be repeat-harvested. One plant, or a clutch of three or four, can be harvested week after week, for months, so long as you tend them well and keep them free of pests.

Growing salad on small urban sites, particularly if you're going to sell it, makes a lot of sense. And the volume of crop to land ratio is really good. Our nine small-scale farms supply approximately 700 people with 100g salad bags each week over the summer, which is pretty amazing.

Tell us about Made in Hackney; what's your mission as London food growers?

Made in Hackney is a pioneering eco-community kitchen based in Stoke Newington. It's a manifestation of the philosophy "think global, act local" and it's our response to the challegnes of global food production.

Specifically, the project is a response to three growing crises: one, how do we feed an ever-growing population in an environmentally sustainable way? Two, how do we halt the spiral of diet-related illnesses in countries such as the UK? And, three: how do we encourage people to adapt their lifestyle to reduce their carbon footprint? They're all pretty big issues. Gulp!

We teach people everything from how to grow organically, source local ingredients, cook delicious meals affordably, compost at home, and make natural cleaning products.

We're currently midway through Urban Food Fortnight: tell us a little about that and what we can expect from your forthcoming Stories talk.

Urban Food Fortnight is put on by Sustain, a fantastic charity involved in a number of sustainable food projects and campaigns. The fortnight celebrates food producers and growers living in cities, and the projects and businesses that champion them.

At Stories, I'll give people a taster of what it's like to be involved in this movement professionally and offer practical tips for getting started with urban growing.

Sarah Bentley is giving a talk as part of Urban Food Fortnight at Stories on Tuesday 23rd September. Tickets are £10 and are available here.