People often tell me that they see plants they love growing gloriously in other gardens but when they try to grow the same plants in their own gardens, they seem to give up the ghost within a season or two. Now, there could be many reasons for these failing garden endeavours. Insufficient sunlight; too much sunlight; insufficient moisture; too much moisture; drying winds; unsuitable aspect – I am sure you get the picture. However, a common theme that crops up when we begin to discuss the various conditions that could be thwarting these floral desires is soil and soil health. This wonderful medium, in which many of our favourite plants grow, is often overlooked when we are looking for ways to improve our gardens. It might not seem the most glamorous of pursuits but helping to improve your soil ecosystem is the key to achieving healthy garden plants that will provide you with maximum pleasure and your local pollinator populations maximum nectar choice.
In this short blog post I will attempt to persuade you of the wonders of the world below our feet and suggest ways you can help sustain that forgotten ecosystem that is so important to your gardening success.
What is soil?
This is a small question with a big answer, but essentially soil is a mixture of minerals, water, air, living organisms and organic matter (the decaying remains of things that were once alive). Soil forms on the surface of the Earth and can support plant life. It is vital to all life on Earth.
Soil biodiversity
Nowhere else on Earth do species live in such densely packed communities than in the soil. One teaspoon of healthy soil can contain more living organisms than there are currently human beings living on Earth. The term soil biodiversity relates to the assortment of living things within soils which contribute to a soil ecosystem. A typical soil ecosystem in your garden might contain the following:
- Several species of vertebrates
- Several species of earthworm
- 20-30 species of mites
- 50-100 species of insects
- 20-30 species of nematodes
- Hundreds of species of fungi
- Thousands of species of bacteria
Protecting and conserving this ecosystem should be one of the main priorities of any gardener. You can achieve this by doing some, or all, of the following suggestions.
Home composting
Composting is an incredibly rewarding way to use much of your household waste. Setting aside a small area of your garden for composting is an important step in starting the production of your own soil conditioner. You want to be adding roughly equal measures of brown material to green material. Brown material tends to be dry, and examples are paper, cardboard packaging, shredded branches and twigs. Green material has higher water content and examples are fruit and veg peelings, grass cuttings, green waste from the garden. You will probably never make enough for the whole garden but the compost you do make will be like black gold.
Mulching
Applying homemade compost, shop-bought (peat free) compost or well-rotted manure to the surface of your soil will improve its health and vitality, help achieve better structure and provide a natural boost to your plants. Don’t dig it in, that is old school thinking now. Various creatures in your soil ecosystem (especially earthworms) will pull the mulch into the soil and you will be preventing the destruction by spade of many beneficial mycorrhizal fungi and plant associations that form in an undisturbed soil. This addition of organic matter will greatly improve your soil’s ability to retain moisture.
Additional soil protection
If you continue to build soil fertility year on year through mulching and refraining from destructive digging, the main threat to your soil’s effectiveness will be damage by extreme weather. This can be longer hot, dry periods that lead to drought or excessive, heavy rains that wash away nutrients. Deep mulching will give some protection by helping to prevent evaporation during dry spells and protecting the soil surface in heavy rains. Try to avoid having bare patches in your beds and borders and this will help prevent the soil from drying out in summer or becoming excessively waterlogged during downpours. If you grow food, use green manures to cover plots that are not being used.
It is a complex world down there where our plants’ roots grow, and we are only just beginning to scratch the surface in our understanding of the various organisms and how their world functions. There is no quick fix (there never is in gardening and anyone who tries to tell you different is selling snake oil) but by following some of the suggestions in this blog post you can begin to build soil fertility and with it a healthy soil ecosystem. It might not be glamorous, but it is the key to growing those plants you have always loved but never seemed to nurture through the first winter.