Instead of writing a month by month maintenance guide for the winter I thought it would be more useful to discuss some overall Winter Greenkeeping Strategies, so here we are.
Bowling green winter maintenance has long been the poor relation in greenkeeping land as many clubs still insist on putting the green to bed to coin a well worn phrase.
This implies that the green will be left to its own devices over the winter and only returned to when the new season is imminent. I know that nobody really goes away and neglects the green’s needs over winter entirely, but I do see a lot of very useful time being wasted in winter when lots of valuable work could be done on the green.
If you are a reader of Performance Bowling Greens you will know by now that I view the winter as a very important period for green maintenance and preparation for next year.
First thing to mention is that regardless of how intensive it was, the autumn renovation program will not have made up for all of the damage done to the green during a busy bowling season, so a thorough winter maintenance regime is essential to ensure that the green is in good condition next spring.
If your green is going through the renovation phase of the performance greens program this is all the more critical.
Around this time last year we waved goodbye to amenity turf approval for Carbendazim, a stalwart fungicide that many had come to regard as a worm killer. This year the warning is out that Iprodione is next for the chop. I actually welcome each pesticide ban that comes along for turf as the process can be, and is usually a catalyst for positive change in greenkeeping.
The frequent use of pesticides highlights the symptoms driven, reactive nature of much modern greenkeeping practice. Each of these chemicals has been withdrawn due to evidence that they are potentially damaging to health or soil, or both.
In the Performance Greens Program I promote a more pro-active approach that focusses on soil health. If we get the health of the soil in order, then the plants can more or less look after themselves. The reality of this for many clubs is that their greens need to go through a transition period to change them from chemical dependent junkies to upstanding, healthy citizens that contribute to the eco-system community in a positive and helpful way.
The withdrawal period is by necessity intensive and can mean that there is more to do than usual, but the aim is to get the soil into a healthy, balanced condition that will naturally promote and support a healthy sward of fine grass that performs to a predictably high standard consistently over the longer term.
This means that the amount of intensive work and indeed expense reduces year on year once the renovation process is underway.
Think about this, as an illustration; a healthy sward of fine grass growing in a well balanced, healthy, microbe rich soil will produce all of its own Nitrogen requirements just through the process of thatch degradation by soil organisms. That’s about 50kg/Ha per year of free Nitrogen. Of course, due to our constant removal of clippings, which takes Nitrogen away, we still need to add some as fertiliser, but we can easily reduce inputs by half, just by maintaining a healthy soil/turf system.
The Importance of Soil Fungi
I might be one of very few greenkeepers who actually welcome fungicide withdrawals, but I do think that in the long term many greenkeepers will see this as a turning point in their practices that led to better green surfaces.
Fungicides kill fungi and the vast majority of soil fungi are beneficial. In fact, we actually don’t know what hidden benefits even the grass pathogenic ones bring to the soil. The only time that pathogens like fusarium become a problem is when we create conditions that favour them. These conditions are already well documented elsewhere on the site and together create a phenomenon I’ve termed the Circle of Decline.
There are important and fascinating messages about soil fungi and the need for a more eco-system orientated focus in the films below. I challenge you to watch them and not come away inspired. Fungicides are very blunt instruments compared to this complexity. Click on the images to watch the films.
Your soil in balance
When I bandy around flippant sounding terms like balanced soil, I’m talking about the need to determine what kind of state your soil is in and then to work on it to bring it into balance in terms of its Chemical, Physical and Biological condition.
Soil chemistry should be the starting point and a thorough soil analysis is the quickest and easiest way to determine what you have to do here. To bring your soil into line chemically means ensuring that there is sufficient Calcium in the soil to maintain close to the ideal base saturation of cations. Cation Exchange Capacity (CEC) determines how well your soil can hold onto and deliver nutrients to the grass plants. CEC is typically very low in sandy soils like bowling green rootzones. This is because they are low in clay and organic matter (humus), the two soil components largely responsible for Cation Exchange capacity.
The base saturation of cations also dictates the pH of your soil, another important aspect of soil chemistry.
We know that the fine, perennial grasses we seek to encourage in our greens like very sandy soils. When we come to realise that the sand content of the soil can affect its nutritional value, it becomes important to quantify how sandy we really need it to be. The answer is very sandy indeed, but it is possible to go overboard on this and many many greens have already. Peak Sand, is my term to describe the point at which very sandy becomes too sandy and we can determine how your green measures up with a simple Peak Sand test, which is included in the basic soil analysis service.
When the soil’s chemical and physical condition is out of kilter, then its Biology will usually be out of balance too. Signs that this is the case is a general, sickly yellow look to your turf in winter, annual meadow grass dominance, frequent disease outbreaks, fairy rings, localised dry patch, slime etc. Essentially all of the usual suspects we’ve come to know as the circle of decline.
Plant hardiness and Potassium (K)
Making sure that your grass plants are prepared for winter will help your green to get through the darker months in much better condition than it would if simply left alone to cope.
Potassium (K) is easily leached from sandy soils and is needed by the plants for winter hardiness against cold and disease. Potassium activates the enzymes used in protein, sugar, and starch synthesis, so is vital to many plant processes. The correct amount of plant Potassium improves drought tolerance, cold hardiness and disease resistance. Potassium ions are highly soluble and leach easily from soils so frequent application is often required. The ratio of Potassium to Magnesium when measured in ppm should be about 1.5 – 2:1.
Cultural Practices and Just Being There
I am often asked “what is the most vital winter operation to maintain a healthy green?”
The answer is easy: Just being there is the most important job. When greens are put to bed and ignored all winter, they usually suffer many times more pain than those that are regularly inspected and maintained through the winter.
Aeration: the most beneficial winter job is the regular deep slit tining with a Sisis Autoslit or similar machine. The effect of this operation is cumulative, so once isn’t enough. Twice a month or even weekly passes with this machine aren’t too much given the right conditions. It should be avoided when the green is very wet or if there is frost, but any other time you can get it done, just do it. This operation slowly relieves the compaction that builds up in the soil all summer. The action of the long, knife shaped tines, breaks up compaction in a volume of soil completely disproportionate to the tiny slit it leaves on the surface. Deep slit tining should be done as often as you can manage it from closing day until mid March (stop earlier if very dry conditions prevail).
Remove Dew/Debris: Dew left on the leaf will encourage disease outbreaks in winter, so it’s advisable to switch or brush it off on a daily basis. At the same time you can remove any debris such as leaves and twigs. Keeping the surface free of debris and excessive moisture will also help to minimise worm casting problems.
Mow the Green at 8mm: Allowing the grass to grow on in winter as a means of helping it to recover is a flawed strategy. Longer growth will result in lush, soft leaf tissue which is more susceptible to disease attacks. Fungal pathogens such as fusarium are also encouraged by the slightly milder microclimate at the surface created by longer grass leaves. In most of the UK the grass will not become truly dormant in winter, so keep an eye on growth and mow the green as often as required to keep it down to 8mm, following the usual rule of not removing more than a third of the leaf at any one time. This means it really shouldn’t be allowed to get much beyond 12mm before mowing.
In winter, it is even more critical that the mower is sharp and that it is set properly with zero contact between blade and cylinder.
Casting worms are a pain and since carbendazim was withdrawn, there is no legal chemical for killing them. Not that you want to kill worms anyway as they provide a fabulous aeration service to your soil and are key detritivores in the early part of the endless recycling process which turns organic material into stable humus. The process is critical for Nitrogen release to the plants and to maintaining an acceptable Cation Exchange Capacity in sandy soils.
Of around 50 species of earthworms we encounter in the UK, only 3 of them produce surface casts, so it is worthwhile to try to follow a strategy for dealing with them that recognises this fact and doesn’t include all out warfare on all worms. With that in mind let me share a heart warming story with you.
When I were but a lad, I was a very keen fisherman and not a very keen gardener. With my seemingly endless quest for fishing worms my parents wrongly assumed that they had hit pay dirt and found a willing, yet free gardener, so they encouraged my piscatorial pursuits with relish. However, I had other plans and quickly discovered the cutting edge of worm procurement technology wasn’t a fork or spade. By simply sploshing a full bucket of warm, soapy water on the back lawn, I could get my hands on plenty of worms to fish all day and have some left over to sell to the less scientifically inclined anglers down at the river. The soapy water makes the worms come to the surface in their droves and very quickly too.
Of course you get nothing for nothing and I found out the hard way that worms gathered in this high tech manner don’t last long and by the time you get to the river they have turned into a ball of dead worm mush. I thought all was lost until an old timer at the river told me that I should have rinsed the worms in cold, fresh water, before storing them in a jam jar filled with dry moss. This extra process allows the worms to live and recover from the collecting process.
It turns out that what is happening here is that the detergent irritates the worms by breaking down their protective mucus coating much as a wetting agent/detergent breaks up an oil slick on the sea. The worms immediately come to the surface to get away from the environment where they’ve experienced this irritation. Without further intervention this causes the worms to desiccate in the absence of their protective mucus covering and eventually to die.
So it’s possible that some level of experimentation with wetting agents could throw up some answers for judicious control of casting worms without doing too much damage overall to the essential worm population. Let me know if you have any experience of this.
Winter survival materials (click on images for more details)
It contains a natural balance of macronutrients and chelated micronutrients (>60 elements), carbohydrates, amino acids, antioxidants and other beneficial organic compounds.
- Turf Hardener and autumn/winter biostimulant
- Promotes stress-resistant, healthy plants
- Hardens the grass against wear and enhances disease resistance
- Reduces the need for inorganic fertilisers
- Used in times of stress to re-balance the trace elements within the plant
Fizzy BioTabs contain 4 Strains of Trichoderma fungi and 5 strains of Bacillus bacteria
Fizzy BioTabs are an all-natural soil probiotic. BioTabs contain the beneficial bacteria and beneficial fungi found in healthy, productive soil and rootzones!
- Replaces Beneficial Organisms-killed by chemicals, drought, compaction and frost
- Assists repair of disease scars and dry patch
- Increases Root Mass
- Make nutrients more soluble and available to the plant
- Converts thatch to humus improving water and nutrient retention
- Healthy plants require less fertiliser and fungicides
MycoGro Granular 5.0.28 Autumn/Winter (20kg)
- A total fertiliser package with soil fungi, bacteria, mycorrhizae, zeolite, molasses and seaweed meal for an excellent, healthy, sward
- Promotes establishment of fescue, bent and rye grasses
- Mycorrhizae improve root mass and increase nutrient uptake
- Increases plant tolerance to drought and stress conditions
- Faster grow-in and establishment of new grass seeds
- Healthy grass growing in a microbially active root zone is less susceptible to and recovers faster from disease.
PHOSPHITE is far more soluble than Phosphate make root and foliar uptake far more efficient, in some plant species. However, very high concentrations can be toxic.
PHOSPHITE is highly mobile and active within the plant and translocates from treated leaves to the roots via the phloem, where it has been shown to provide some control over root diseases i.e. Phytophora.
- Can increase the efficacy of fungicide applications
- Promotes the natural control and resistance of some plant fungal diseases
- Stimulates the plants own defence mechanisms and biologically active metabolites
- Highly soluble so readily taken up by roots and leave
- Translocates to all areas of the plant
BIOSTIMULANTS to promote the production of plant hormones essential to combat stress caused by disease and dry patch.
WETTING AGENTS to aid water penetration and dispersal
POTASSIUM (0.0.18) to increase cell production and harden the sward.
- For rapid recovery of disease scarring and dry patch damage
- Promotes the growth of healthy turf, less susceptible to stress
- Provides long lasting green-up
- Contains wetting agents to aid water penetration and prevent dew formation
- Use as a treatment or a preventative
Soil Chemistry and Peak Sand Analysis
Get to the bottom of all your green problems and come out fighting in 2018.
As always, if you have any questions please feel free to drop me a line.