It’s funny how things change. Or, rather, how our attitudes to things change. Take, for example, antibiotics, which only a few short decades ago were considered magic pills for the mildest of ailments, before scientists discovered that their over-use was leading to increased resistance, as well as to the destruction of important “good” bacteria in the human gut, with significant consequences for long-term human health. Cue the growing popularity of probiotics and homemade products such as kefir (a fermented milk drink) that help re-seed or re-inoculate the human gut with a mixture of beneficial live microorganisms.
But it’s not just humans. Numerous kinds of beneficial bacteria are also present in vast quantities in healthy soil, as part of a diverse community of micro-organisms that play a variety of crucial roles in our gardens.
These include encouraging the breakdown of organic matter, speeding up the process of photosynthesis and inhibiting the spread of plant diseases and soil-borne pathogens. Note that I say healthy soil; very often that complicated and mysterious balance is out of whack as a result of flooding, compaction, pollution, or the regular use of chemical fertilisers and pesticides.
How can we, as gardeners, help restore that fundamental balance? Scientists are discovering that one of the most effective ways is by adding beneficial microorganisms back into the soil, a method described by some as probiotics for the garden.
One example of this is EM (Essential Microorganisms), a product created back in 1982 by a Japanese scientist and horticulturist by the name of Teruo Higa, and now used by gardeners all around the world (rumour has it that both Alan Titchmarch and Prince Charles are fans). A liquid mix of different beneficial bacteria, yeast and fungi (all naturally-occurring and mutually compatible), EM restores life to the soil with wonderful results.
It is, for example, being successfully used both as a preventative and as a very effective treatment for box blight (Cylindrocladium sp), the horrid fungal disease that has wrought such terrible damage upon box hedges (Buxus sp.) in recent years.
In the Netherlands, tulip growers are also using it as a natural control against other common soil-borne diseases.
Here in Ireland, horticulturists including the Laois-based gardener Tanguy de Toulgoet use EM to clean pots, tools, polytunnels, glasshouses, even beehives. In this case, it works by colonising surfaces with large quantities of beneficial microorganisms, unlike bleach or other harmful disinfectants that work by killing all microorganisms including the good ones (for the same reason, EM is increasingly being used in hospitals).
EM is used in farms and horticultural nurseries to inoculate not only the soil but also young seedlings, transplants and growing crops. A version of it is also used in Bokashi bins, where it helps to quickly and efficiently digest food waste through fermentation, with the resulting odourless product suitable for use as a soil enricher.
Used in the compost heap, not only does EM speed up the process and allow the breakdown of plant waste to continue at much lower temperatures than with a conventional bin, but it also changes the compost’s chemical composition for the better (much less chloride, far more carbon).
Another fascinating product that improves the structure and fertility of the soil with very tangible benefits for gardeners is Soil Renew, which was created by French farmer Marcel Mézy back in the 1990s. An organic soil additive, it too uses the action of soil microorganisms to encourage the rapid production of humus.
Humus is the non-living organic matter in soil that acts as a storehouse or reservoir for nutrients essential to plant growth, and is key to good soil structure and resilience. Without humus, soils turn into deserts, or as Mézy himself says, “When humus goes, man goes…”
Just like EM, those who’ve used Soil Renew report a myriad of benefits, from an explosion in the size of their garden’s earthworm populations (and thus in the number of garden birds), to stronger, more steady growth levels, greater yields and tastier crops (always a boon in the kitchen garden), lusher lawns, and a significant reduction in plant pests and diseases.
Just like EM, it too has the ability to bring dead soils back to life, while its sister product, Compost Renew, also uses beneficial microorganisms to accelerate the breakdown of organic matter, resulting in a compost that’s rich in humus and high in nutrients.
So the next time you find yourself fretting about those bald patches on your once-bushy box hedge, or the greenfly on the roses, or wondering why your veg patch isn’t anything like as productive as it used to be, don’t reach for the fungicides, or the insecticides or the artificial fertilisers straight away, but pause for a moment to consider some of the much more exciting, effective and sustainable alternatives. Beneficial soil microorganisms.
Like I said, it’s funny how things change.
For more information about EM, see effective-micro-organisms.co.uk. Irish suppliers include Natasha Harty (thehartys@eircom.net)
For more information about Soil Renew, see soilrenewireland.ie and marcel-mezy-environment.com.
THIS WEEK IN THE GARDEN…
l To stop it from getting too large, as well as to encourage an abundant production of its wonderfully decorative, drooping clusters of fragrant lilac-blue/white flowers in early summer, wisteria should be pruned twice a year – once in late summer and then again in late winter (any time from now until the end of February) when the plant is dormant.
So if you were organised enough to cut back those new, whippy growths to five or six leaves last summer, then now is the time to prune them again, back to within two to three buds of the plant’s main framework.
These will form the short spurs that will produce those wonderful flowers later in the year. For a demonstration video, see rhs.org.uk l Winter pansies add a splash of welcome colour to containers at this time of year, but to encourage the plants to keep producing new flowers and prevent them from setting seed, it's important to regularly dead-head any faded blooms l If a spot of mild weather tempts you out into the garden to do a little light weeding, try to do so with a gentle hand, and with your eyes peeled for the earliest of the spring bulbs, whose snouts are already pushing their way through the ground but can easily be damaged by a sharp hoe or a heavy foot.
Also regularly check those growing in pots or containers to ensure that the compost doesn’t dry out.
