Monoculture is bad news and that's a fact. Take nature as a perfect example... You don't tend to see plants growing on their own in natural settings. Instead you're more likely to find mixtures of plants growing together in groupings that benefit each other, thus providing the best environment for each different species to flourish. However, when you look at agriculture and growing on all scales there rarely seems to be space for this kind of diversity. Plants are grown together in large, single species blocks that leave them more prone to disease and attacks from pests and can also leave the soil prone to depletion in specific nutrients depending on the crop that has been planted there. Even in organic gardening where companion planting is used the focus is placed upon single crops intermingled with beneficial crops rather than the kind of happy and healthy poly-culture that is more common in nature.
This is style of cultivation is key to Permaculture and is perfectly exemplified in the traditional kitchen garden with mixed beds where every plant plays a specific part in maintaining the health and well-being of the garden. I've always been interested in growing in this way but it's only been in this season that I've really been brave enough to experiment with poly-cultures on my plot. As much as anything because my allotment is on a pretty old school site and I didn't want to rock the boat too soon after taking my plot on.
The bed in the picture is one of my favourites on the plot at the moment and is a great example of poly-culture in action. Leeks are dotted around surrounded by carrots, with the oniony scent of the leek acting as a deterrent to carrot root fly. These two crops are intermingled with lettuce, mizuna and beets all of which were planted through casual broadcast of seed meaning they have come up where they feel most comfortable themselves. There are also a couple of Swede which were intended to keep the rabbits occupied and prevent them eating more valuable crops (they LOVE swedes you see) However, much to my surprise, the swedes even seem to have been protected by this way of planting with the bunnies taking a nibble of the odd leaf but not decimating the whole crop like their did last year.
The whole bed is topped with three tomatillo plants that offer light shade with their glorious, arching branches and that seem to appreciate the soft, well cultivated soil that the other crops are also enjoying. So far the signs seem to be good with high yields and healthy plants. And the other added benefit? The bed looks absolutely gorgeous to look at which can never be a bad thing in any garden as far as I'm concerned. It'll be poly-culture all the way on Plat 45 next year, I can tell you!