Dr Deidre Charleston - Things are heating up!

As I write my first blog for Symbio, I think back on winter, and the torrential rain and storms which battered our country and never seemed to stop.  Today however, evidence of a new season cannot be ignored.  I am listening to the morning chorus and it is getting earlier and earlier, daffodils create splashes of colour in the verges, and I have had to take the lawn mower out of the garage to tackle the growing grass.  These signs of spring cannot be ignored, and despite the difficulties we face with Covid-19 and the restrictions on our lives, nature and life underground continues unaware of the turmoil above.  Soil temperatures start to rise, microorganisms move closer to the surface and the soil food web takes off.  During the winter months microbial populations decline, and metabolic activity decreases.  As the days get longer and warmer plant photosynthesis increases, and more carbon is produced and released from the roots, feeding the soil microorganisms and allowing populations to increase.

As spring and summer approach we can improve turf health by encouraging beneficial soil microorganisms.  Soil microorganisms thrive on a good food source, a good supply of water and plenty of air.  Over the winter many areas will have suffered from water logging, and some may have even been submerged under the deluge of rain making it impossible to carry out usual management practices.  However, as the sun comes out and things start to dry up, good aeration practices will be crucial to encourage soil biology and population growth.  Thatch may have built up, starving the soil microorganisms of air and water.  Good aeration practices will start to encourage population growth.  However, even with good aeration, if the thatch layer is not broken down the air and water will only reach the soil directly surrounding the tine holes or hollow cores.  Over the winter period bacterial and fungal populations will have declined.  Bacteria thrive on the easily accessible carbon sources from simple sugars found in root exudates; and are usually the first microorganisms to start building up their numbers in the spring.  The fungi will follow.  Fungi are able to feed off the more complex carbohydrates in cellulose and lignin, the main components found in thatch.  Good populations of fungi will help to break down thatch allowing air and water to penetrate the soil evenly (Symbio Thatcheater; Symbio Green Circle).  Once the air and water can reach the soil, the soil food web will grow and become more complex, with populations of protozoa, predatory nematodes and arthropods developing.  Disease may start to rear its head as the temperatures start to rise, but by kickstarting biology and bringing balance back to the soil food web the soil microorganisms can outcompete the pathogens and help turf to recover (Biotabs).

As the days get longer and plants increase photosynthesis, they will start to grow more rapidly and will require good nutrition to continue their growth.  A healthy soil food web can often support plant nutrition.  Mycorrhizal fungi associated with fine grass species are able to extract nutrients from the soil and provide these to grass plants, allowing a rapid establishment of these species without the need for excessive fertiliser application (Mycorrhizal Seed Coat; Mycorrhizal Inoculant).  As bacteria and fungi break down and convert thatch to humus, the cation exchange capacity in the soil is increased, making more nutrients available to plants. In spring when the growth of both plants and soil microorganisms is rapid, it is important to provide a good food source for soil biology to increase population growth and thus support plant nutrition (CMS Shoot, Caviar, Fulvic Booster, Biobooster Fish).  If additional plant nutrition is required, then it is important to conserve the populations of soil microorganisms, and fertilisers with a low salt index are preferable (Mycogro Fertilisers).

So as I gaze out my window at the growing grass and contemplate another weekend of mowing, I think about the life stirring below the surface, and I am reassured that the turmoil of Covid-19 will go unnoticed by this population.  That it will continue to grow and thrive and work for us, if we remember to nurture it; and just give it a bit of air, water and food!

During these turbulent times when we are faced with limited budgets and a reduced work force, take the opportunity to allow soil biology to do the work for you, and see how bringing life back to your soil can reduce plant (and human!) stress, produce excellent results and save you money.  If you would like to discuss how Symbio can help you to bring life back to your soil then contact us to find out more about our products and cost saving programs.

Watch this space for the next blog, where we will look at ways to manage water stress, and improve tolerance to pests and disease.

Dr Deidre Charleston 

deidre.charleston@originamenity.com

01428 685762