Diversity is important in life, and important for our lives on this planet. Valuing diversity in all areas of existence can help us to see a way forward for humanity. Not only is variety the spice of life, diversity also plays an important role in maintaining a well-functioning system – whether we are taking about broader society, an ecosystem, or, on a smaller scale, individual polytunnel gardens. There are many ways in which we can value diversity in our polytunnels and in our everyday lives. Valuing (and therefore increasing) diversity in a permaculture polytunnel is a good way to begin your journey towards a more ethical, sustainable future.
The most obvious way, perhaps, to improve diversity in a polytunnel is to simply choose a wider range of crop types to grow. Perhaps it is time to branch out and try something you've never tried before – how about kohlrabi in addition to the more familiar brassica broccoli, Calabrese etc... or versatile and useful Asian greens such as mizuna, mibuna, pak choi etc...?
Of course, you could not only branch out in which vegetables, herbs or fruits you choose to grow but also in the varieties of each that you plant. By choosing a range of interesting and perhaps endangered heritage plants, you will not only improve the diversity in your polytunnel but can also help improve (or at least retain) the diversity of the edible plant stock where you live.
Valuing diversity means sometimes embracing things that have grown in the 'wrong' place, or unexpectedly. Weeds can also be useful in a polytunnel – think about using the natural diversity of local plant life in your region to enhance the ecosystem in your polytunnel garden. Weeds have their uses in the home, or can be used to help fertilise or return nutrients to the system.
Weeds can also help to attract wildlife. Encouraging various different creatures to spend time in or take up home in your polytunnel can make your job easier as an organic gardener. A diverse ecosystem will be more likely to keep pests naturally in check through natural predation. Pollinators, of course, will also help your gardening efforts. Diversity in terms of wildlife will help to ensure everything in your polytunnel continues to tick over nicely.