Over the weekend I spent a bit of time in the garden, weeding, composting and mulching. I’m preparing beds for the month ahead, keeping myself motivated through the hard graft (the gardens here are seriously neglected) by daydreaming about the harvests to come. As well as thinking about what will do well in my garden and what I like to eat I’ve been giving a bit of thought to biological and genetic diversity and wondering how my plantings might help to keep rare species and varieties alive. So what’s the problem with food crop diversity? The limited types of plants we grow, and the few varieties (genetic strains) of those plants we do sow. Modern agriculture promotes the growing of only a small sub-sample of possible food plants. The plants grown have been selected over the years for various reasons, including high yields, easy harvesting, long shelf-life, market familiarity and easy processing. As western industrial systems of agriculture have expanded across the world, western crops have moved with them, replacing traditional food plants. We’ve lost awareness of many alternative food plants along with the knowledge of how best to grow them, and along the way we’ve lost access to many of the food plants best suited to growing conditions in many parts of the world, and to the conditions predicted in a climate-change impacted future. As farming has industrialised we’ve also become reliant on a small handful of the known varieties of the plants that have become our dominant crops. Where a century ago there were 400 known varieties of peas in cultivation, now there’s only 25 that are commonly grown and most of the original 400 have gone extinct. Although it might not seem important – after all we still have peas – this loss of genetic diversity is really quite worrying: genetic diversity is the thing that lets us adapt crops to changing conditions, environments and diseases.[1, 2] If we lose the genes, we lose the means to adapt our food plants to new growing conditions. This is a huge concern for food security, putting our agricultural systems at risk of collapse due to drought, climate change, plant diseases and even global politics – agribusiness is big business. The UN’s Food and Agriculture Organisation estimates that 75% of crop biodiversity has been lost from the world’s fields – that’s how big the problem is. Some governments and science organisations are so concerned that they’ve established a secure seed bank to preserve rare seeds as best as possible, behind steel doors in a vault built into a mountain beneath the permafrost in the Arctic circle.[1, 3, 4]
Although it’s not only the lost biodiversity that’s the problem – there’s related issues about fertilizer, pesticide and herbicide use , as well as lost potential medicinal and biotechnological properties, farming knowledge and cultural traditions – it’s the part that I can do a little something about in my own back yard*. I can plant unusual crops and rare varieties of veggies in my little patch, preserving diversity when I collect seed for the next year and expanding my culinary world at the same time. I’ve taken my day-dreams of fresh greens and home-grown spuds and checked them against growing guides and seed catalogues, getting an idea of what plants and varieties will do well on my fine, claggy soil (I could spend hours looking through seed catalogues, dreaming of gardens that will never be…). I’m choosing for suitability, flavour and biodiversity, tracking down suppliers of unusual, heirloom and organic seeds. There’s a world of weird veg out there that I can’t wait to explore! Backyard-friendly unusual veggies that I’m contemplating growing include salsify, skirret, salad burnet, oca, mizuna and elephant garlic. I’m also planning to plant unusual varieties of more familiar crops:
…and whatever else I come across that’s just a little different. I’ll find out what works, save seed from the successes and grow them again next season, slowly selecting the genes that do best right here, creating a garden with a genetic profile that’s all it’s own.
What usual food plants or rare varieties are your favourites? What’s the weirdest edible you’ve ever grown? Know any good sources for heirloom seeds or kooky seedlings? Let us know what makes your garden a little more biodiverse! Sources for seeds or unusual seedlings (Australia):
References:  http://www.croptrust.org.  Food and Agriculture Organisation of the United Nations (2010) Crop biodiversity: use it or lose it.  Longyearbyen (2012) Banking against Doomsday; The Economist, March 10th, 2012.  http://en.wikipedia.org/wiki/Svalbard_Global_Seed_Vault.  Altieri MA (1999) The ecological role of biodiversity in agroecosystems; Agriculture, Ecosystems and Environment 74, Pp 19–31; Elsevier.  Altieri MA & Merrick LC (1986) Agroecology and in situ conservation of native crop diversity in the third world; Chapter 41 in Wilson EO (1986) Biodiversity, Part 3; National Academy of Sciences, Smithsonian Institution, USA. * I can also do something about it through my grocery shopping, steering clear of the supermarkets for my produce, buying meat from rare-breed livestock and selecting unusual veg from the farmer’s market and local grocer.