This article is designed to enable even the least experienced volunteers or green keepers in bowling clubs to follow a plan of action to maintain the bowling green in good condition throughout the season.

In conjunction with the article I have negotiated a package of the fertilizers and other treatments which I would recommend to carry out the advice I will be offering. This package is very competitive and will enable the bowling clubs to budget for the year ahead knowing exactly what the required funding will be. We can also supply all materials in the package on an individual basis, although delivery costs will be a little higher.

With the package you will also get ongoing advice by telephone or e-mail, and help in sourcing all other materials and machinery. If you’d like more details, or to talk it through, get in touch.

Mowing one of the Northfield greens between the morning and afternoon games in the Ladies World Championship

Mowing one of the Northfield greens between the morning and afternoon games in the Ladies World Championship


Mowing is the single most important operation in maintaining a good surface. The mower has to be a specialised fine turf mower with at least ten cutting blades, there are no cheap alternatives.

There are a variety of manufacturers and a huge difference in pricing. The Dennis has the advantage of interchangeable cassettes for various tasks, such as spiking, verti cutting, scarifying, and rolling.

The easiest mower, in my opinion, to use and set, and also very good value, is the Lloyds paladin, this comes with an optional brush and comb set, very much recommended, which are both very useful in providing a good playing surface.

A typical professional greens mower. In this case with a comb fitted rather than a groomer.

I do not advise bowling clubs to spend the substantial additional funds on a groomer attachment as these are difficult to set, and can cause problems if not used properly. A good second hand scarifier/verticutter can be bought for less, and is far more versatile.

The cutting cylinder and bottom blade must be in good condition and sharp, then set to achieve a clean cutting action.

Blunt or badly set mowers are the primary cause of poor bowling surfaces as it causes uneven growth and tears the leaf tips allowing disease to thrive, and also stunts regrowth.

In most cases the machine will need a sharpen, and possibly even a new bottom blade, halfway through the season to retain a good finish.

It is always worth having a back up machine in case of break downs, and also to cover during servicing etc.

Checking the blades.

The cutting action can be checked easily by carefully inserting a piece of writing paper between the cylinder and bottom blade, then turning the cylinder very carefully by hand. The paper should cut cleanly along the length of the blade, if not it certainly wont cut the green properly.

With the mower properly set for cutting, the height of cut is the next step at the start of the season. The aim is to have the green being cut at no more than six mil by the end of March, so if the mower is set above that, then over the last two weeks in March lower the height by a half mil at a time till the six mil is reached.

I would hope to be mowing at least twice a week at this stage, depending on weather of course. In the South of the UK the timing can be as much as two weeks earlier so take your location into account.

Mowing direction should be from corner to corner, although the angle can be varied a little, alternating between corners on each cut, during the playing season. In the close season the direction should be altered to four different directions including straight up and down and across the way to eliminate any nap, grass lying in one direction causing runs on the green (see verti-cutting to avoid this), that occurs during the season.

Attaining optimum cutting height.

To check the height of cut a straight edge is set between the front and back rollers, the bench setting of the cutting height being the space between the straight edge and the edge of the bottom blade nearest to the cutting cylinder(see pic).

I say bench setting, as that is not necessarily the true cutting height as that depends on how firm the green surface is. On a soft, thatched surface the bench setting will be higher to compensate for the mower sinking slightly into the surface. This can only be assessed by trial and error.

Most new mowers come with a setting bar, that is a straight edge with a screw through it which slips onto the inside of the bottom blade to help with setting.

Early April

Over the first two weeks of April the cutting height should be lowered by a half mil each week, with frequency upped to three times per week. Whether it goes lower than 5 mil later in the season depends on many factors, examples being whether members like slow or fast greens, or that fine grasses such as fescue bowl well at five mil, whereas annual meadow grass has to be cut shorter to get a fast true surface.

For the rest of the season the height can be varied slightly up or down depending on weather and/or speed requirements. Cutting frequency should be maintained at a very minimum of three times per week, although it has to be noted that the more often mowing is carried out the better the surface will be.

At the end of the playing season the mowing height should be increased to a maximum of eight mil, and the green given a trim whenever the weather permits throughout the Autumn and Winter. This helps to keep the surface dry and reduces the possibility of disease outbreaks.


What is scarifying.

Scarifying is the act of using vertically rotating blades to cut into the surface of the green to remove dead and dying material known as thatch and fyber. This opens up the sward, letting in air, and also vertically prunes the grass plants which stimulates fresh strong lateral growth. Scarifying should never be carried out in the Winter months as exposing the grass crown, the growing point, to frost, can cause serious damage and even death of the plant.

There are various methods of scarifying bowling greens, they are thatch removal, thatch control, and grooming, the last of which is a small vertical cutting reel fitted in front of the mowing reel on the mower.

The thatch removal reel is quite severe on the sward so is best only used in the Autumn during the renovations, and possibly in early Spring before the start of the season if there is a thatch problem. In the Spring the recommended method is to carry out the first operation of verti cutting around two weeks after the application of the early spring fertilizer in mid to late March.

This ensures any moss has been killed for easy removal, and the grass is vigorous enough to fill in very quickly. This operation is fine to carry out straight across the green.

Regular in season verti cutting.

If you have your own scarifying machine then verti-cutting should be carried out ideally every two to three weeks throughout the season, except for periods of drought when the grass is stressing. Alternate the direction between opposite corners each time.

Alternatively, verti-cutting units can be hired in, and  it will be down to budget restraints as to how often the work is done. In the close season verti-cutting or scarifying can be carried out in straight lines across the green.

If a groomer is fitted to the mower then it should be set at around two mil above the cutting height for optimum effect, but only used when the grass is not under stress from drought. If verti-cutting is not being carried out then the groomer can be set more aggressively, but no lower than one mil above the cutting height.

Fertilizers and Conditioners

Why they are needed.

Fertilizers are applied to supply nutrients to the grass plants to help them grow healthily and withstand the wear and tear of feet, bowls and machinery. Conditioners are materials such as seaweed that help the plants to take up the nutrients by improving the soil through increasing the microbial and bacterial content in the soil, and also supplying many micro nutrients, thereby giving a much healthier growing medium.


The first application of fertilizer should be applied around mid to late March during the first spell of mild weather, again in the South of the UK this can be earlier. A good sign for the inexperienced groundsman to look out for when the time is right is the farmers feeding their fields, one of the only times you would ever follow farming methods!

On bowling greens the fertilizer should contain a good iron content to kill any moss for easy removal, and no phosphate or potassium. My preferred formula is 9 to 12% nitrogen, and at least 9% iron. This will read as 10.0.0. 9%fe or similar on the product description. A good quality spreader such as this one is required for all granule or powder products.

During the season

I prefer to use liquid fertilizer during the season as it does not interfere with the bowling in any way, granules and powders are very messy, sticking to bowls and shoes, and can stain badly. My preference is to apply a liquid containing nitrogen, some potassium, and seaweed around the end of May, then the same again mid to late July.

An alternative, though more labour intensive, is to apply lesser quantities more often. This will give a more even growth pattern throughout the season, which from a playing point of view, as well as the maintenance, is very desirable.

For example, this Maxicrop conditioner is a proven high quality seaweed extract.

This should be supplemented by applying liquid iron, soluble sulphate of iron or chelated iron (find a good liquid iron supplement here) roughly half way between the liquid feeds and in mid August, but care must be taken not to apply iron when the grass is drought stressed as this can cause damage by scorching.

In a wet season the frequency may have to be increased to compensate for leaching out of the nutrients, and of course this applies to varying weather patterns in different parts of the country.


During the Autumn renovation my recommendation is to use a low nitrogen/high potassium feed, with micro nutrients, iron and seaweed(find a good example here) to stimulate a slow and strong recovery from the seasons stresses. Over the Winter period two applications of lawn sand, the first around late November, the second early February, are recommended to harden the grass and keep moss at bay.

Wetting agents

Wetting agent is used to increase the rate at which water disperses and is a very useful tool in helping to avoid flooding, or heavy dews forming. When added to liquid fertilizers it helps the plant to absorb the nutrients quickly so avoiding loss by evaporation.

Wetting agent should be added to each spray application of fertilizer and iron. The other time to use wetting agent is immediately after the autumn renovation as it aids seed germination and grass recovery after aeration.

See the specific articles on best fertilizers for the types recommended in each season.

This SISIS aerator is ideal for bowling greens as it is very portable and fits through most gates

This SISIS aerator is ideal for bowling greens as it is very portable and fits through most gates


Why aerate

Air in the root zone is essential to the health of the grass plants that make up the playing surface as the spaces are where the roots grow and absorb the nutrients required to produce a quality surface.

Aeration is also essential to allow water to penetrate the surface and drain through the root zone without water logging and consequently drowning the plants.

Methods used

The most effective method of aerating is by slit tining, ideally alternating operations between depths to avoid forming a compacted pan at one level. The frequency of aeration depends a lot on the greens root zone make up as, for instance, sand naturally drains much faster than loams or clay soils. Sand root zones do not compact as badly or as deeply as the others either.

I prefer to use a combination of deep slitting, six to eight inches, every month from October to March, and chisel tines alternately in each of these months in the two weekly gaps between the deep spiking. Over the Summer months the chisel tines, or solid pencil tines, can be deployed once per month to keep the surface open as there is no danger of these opening up because of dry weather.

If a sarrell roller, a roller with lots of small spikes around two to three centimeters long, is available, it should be used every two weeks or so throughout the season. It is important to always spike in the same direction as this has been proved to be the most effective in producing good root growth, and avoids damage to the turf by cross hatching. Always spike in straight lines across the green as there is much less turning required, and it is much quicker.

The other methods of aeration are verti-draining and hollow coring. I only recommend hollow coring if there is a very serious thatch problem, or the soil is very heavy requiring  modification to improve drainage, and should only be used as part of the Autumn renovation program. Hollow coring is certainly not required on a sand based root zone. Hand tools to carry out operations on worn areas are very useful on any green. If a specialised tool is not available, a garden fork inserted vertically, then eased back to lift the soil works well.

Verti-draining is a deep operation using 30 centimeter solid spikes and heaving the soil as you would do with a garden fork. It is very effective for deep seated compaction on heavy root zones, but there has to be underlying drainage in place or it will not work, and in fact can make things worse by further saturating the root zone as the water has no where to go.

If verti-draining is recommended then is should be as part of the autumn renovation along with slitting or hollow coring. The verti drain is a tractor mounted machine, so before booking this you must ensure access to the green is possible.

Water Application

Watering turf can be a very contentious subject as there are so many variables.

When watering fine turf the object is to keep the grass alive, not necessarily keep it bright green, as to do that would lead to a soft easily damaged surface and very shallow rooting.

Automatic watering systems are great when used properly, but since their  introduction have lead to many severe problems, particularly when being controlled by amateurs who only think it can be switched on every night with no idea of the consequences.

The aim should be to soak the root zone thoroughly every three days or so to ensure the grass roots are kept supplied with moisture. This is where spiking and wetting agent are great allies as they allow the water to get into the root zone quickly, thereby reducing water usage and providing a much healthier playing surface.

If the temperature is very high, then a short one minute spray during the day can help to cool the turf canopy, and the soaking could be increased to every second night.

It is best to water early in the night as far less water is lost into the atmosphere during the cool of the night.


In direct opposition to aeration, rolling does cause compaction, irrespective of which kind of roller is used. Rolling does produce a faster, truer surface, but should be used with caution, especially if frequent spiking is not being carried out.

The pedestrian tru level roller is a good tool, having three rollers to spread the weight, but is labour intensive, really only suitable for use before big competitions. The motorised version of this is heavier, but because of the three rollers spreading the weight, is a valuable tool to speed up the green on a weekly basis, again as long as aeration is regular.

If not owned these can be hired for big competitions if speed is required. I would not advise the big single rollers other than just before the start of the season because they roll into and over undulations and do not level in any way.

Applying topdressing evenly with a shovel.

Applying topdressing evenly with a shovel.

Top Dressing

Top dressing serves two purposes. First it is used to dilute the build up of dead and dying grass material in the top two or three centimeters of the green which prevents the build up of thatch, and spiking then takes some of the top dressing down into the root zone, both of which aid drainage to keep the surface dry and healthy. The second purpose is to keep the surface level by using a straight edge to smooth out any abnormalities.

I always advise using a medium course top dressing that has been properly tested. My preference in most situations is to use a straight sand dressing as this does away with the unavoidable variances in organic content, and the drainage characteristics are consistent throughout. I can advise on your nearest approved supplier.

The main times to use top dressing is in the Autumn to finish off the Autumn renovation, when the the application can vary from three tons to six tons per green depending on whether the green has been hollow cored/verti-drained, or only been spiked, and also on the budget available as top dressing is liable to be biggest single expenditure on materials for the green.

Ideally the green should be fully dressed again in Spring, using around three tons per green, but at the very least the playing heads should be given a dressing at a kilo or so per square meter. A supply of dressing should be kept in stock to allow the heads to be dressed once a month throughout the season to help them withstand the wear and tear of play.


It is good practice to apply good quality grass seed, particularly on the heads, after aerating and before top dressing, during the Autumn renovation. The rate for over seeding is recommended at twenty five grams per square meter, and should be a mix of grass types suitable for producing a first class bowling surface. I deal with a very reputable seed supplier who, being a family company, provide an excellent choice of grasses fit for purpose.

I have not mentioned any disease or pest problems as these are best dealt with as a separate issue. Disease, mainly fusarium, can cause a serious problem, but I personally have not used a fungicide for more than thirty years as the practices I recommend are designed to produce a healthy grass sward that is not prone to disease. Some patches will occur but are easily dealt with by using iron and top dressing. I can advise on more serious occurrences if disease is already present due to past practices.

Worms can cause a lot of problems, particularly on heavier soils. Regular switching and/or brushing is essential throughout the year, especially before mowing. There are some chemicals available which I can advise on if required (contact me here). Worms do not like iron, do not like sand, and are not nearly as active in well aerated soils, so my maintenance program greatly discourages worm activity.

The only other pest that causes serious damage in turf is the leatherjacket, the grub of the cranefly, which eats the roots and shoots of grass plants, resulting in death of the grass in the worst cases. There is often also serious damage caused by birds and animals digging and scraping the surface looking for food.

Very cold Winters will reduce the population, and there are now no insecticides available for control. Nematodes are being experimented with, but are expensive and not yet proven to work. Best method is to ensure the sward is healthy, with a good root structure, to withstand the attacks better.

It is possible to remove them manually by applying a heavy dose of wetting agent after aeration, which will bring them to the surface where they can be removed by brushing or mowing.


Weeds can be a problem, particularly if using top dressing containing soil or if hollow coring often. I do not advocate ever spraying a full green with weedkiller as it certainly sets back the grass a little at the same time. Most weeds can be lifted out by hand, using a grubber or small fork, but if there is an infestation of ground hugging weeds, like chickweed or pearlwort for instance, spraying with a readily available selective weedkiller (this one from Westland) would last 2 or 3 applications, used selectively) using a hand held spraying bottle will do the job. If you require advice on this please get in touch.

One of the biggest problems I see on bowling greens is a reluctance to regularly move the heads to spread the wear. There should be at least three settings in each direction on any standard sized green, with these being changed on a set rota to ensure an even spread of wear throughout the season.

I always advocate a single circuit round the edge of the green with the spare mower set at around seven to eight mil to protect the green edges. This is legal in the rules, and is good practice, but can only be done easily if a spare mower is available.

As I have said this is a definitive guide to maintaining a bowling green but in many cases the ground conditions, weather, and surrounding issues such as big trees will entail altering or modifying a program to produce the best playing conditions.

This is where an initial assessment and on going advice can be greatly beneficial to any bowling club using our service. If you want to talk it through, please do get in touch