Why is diversity important in the garden?
In the natural world, diversity is the perfect model for sustainable ecosystems. Diversity is a major factor in preventing pest and disease build-up because of the way in which organisms interact. When any one species becomes dominant in an area, its predators will move in to take advantage of the bounty. Eventually, they will reduce the numbers of the dominant species, restoring the balance of Nature.
In the past, farmers relied on natural methods of farming because chemicals were not available to them. Now, it is possible to grow crops as monocultures, because the use of pesticides has given us a way of controlling competition. This unnatural form of agriculture has created a range of unintended problems. We can learn from these mistakes by planting a diverse range of species in our gardens, thus naturally reducing pests and diseases.
The advantages of heirloom varieties
Heirloom plants are varieties that have been handed down through decades, or even centuries, from farmer to farmer and gardener to gardener. For roughly 12,000 years, human civilization has been based on agriculture and horticulture. During this time, thousands of genetically unique strains of fruits and vegetables have been selected and bred by farmers and gardeners. They represent a genetic heritage that is disappearing from commercial horticulture, where large-scale factory-type production demands that plants conform to strict guidelines to fit into mechanized systems.
By contrast, heirloom varieties are a celebration of genetic diversity whose greatest strength is the fact that there are individuals within each crop that mature a bit earlier or are more resistant to pests and diseases. Such characteristics are a tremendous advantage in the organic garden, where the produce does not have to fit into a narrow commercial window.
Fortunately, there are many gardeners who recognize the value of maintaining genetic diversity for future generations. Consequently, around the world various non-profit organizations have been formed to store seed or to help gardeners and farmers form networks that enable them to swap seed and vegetative material of heirloom plant varieties.
The many vital roles of herbs and flowers
Introducing a wide range of herbs and flowers into your organic garden will have benefits. They will help attract an increased range of birds, insects, lizards, and other animals. Insects and birds will act as pollinators for your fruit and vegetables resulting in increased yields. Many of these creatures will also help to control pests. Inevitably, there will also be some negative consequences, such as birds feeding on fruit, but the diversity you create will be your insurance policy in that if one food crop is decimated there will be a host of others that can replace it.
Herbs often have aromatic oils that give their foliage and flowers as characteristic perfume. Herbs such as pyrethrum and garlic can be used to create organic remedies for pest and disease problems. In addition, such plants release oils into the air and soil that surrounds them, thereby helping to repel pests from your garden naturally. I have been a gardener for over many years and I have grown thousands of different plants, both commercially and personally. Diversification is a great insurance policy in everyone’s garden.