With this year’s Wimbledon already started, I am sure everyone will be rooting for Murray to retain crown on his favourite grass court surface.
The grass courts always look immaculate on TV and are a credit to the hard work of Neil Stubley’s team of groundstaff at Wimbledon.
The Wimbledon fortnight will no doubt have stimulated many people to get out and play some tennis. Coupled with the long daylight hours, outdoor tennis facilities will be busy coping with the demand, especially clubs with grass courts.
The weather has also been challenging, with an ever changing front bringing spells of sun, rain and fluctuating soil and air temperatures. We would hope that, during July, temperatures will rise into consistently high double figures (18-20 degrees C), promoting some decent growth. Hot warm weather. however, often sees the need to irrigate to replace lost evaportranspiration rates.
Evapotranspiration rates will be high in July, water losses can be between 4-6mm a day. Irrigate uniformly and ensure you replace what has been lost. It is important to ensure that the water gets deep into the rootzone, to a minimum of 150mm to encourage deep rooting. Check with a probe. Allow to dry out and repeat the irrigation process.
Allowing surfaces to remain dry for a period of time can lead to problems of dry patch, a condition that prevents water infiltration into the soil and thus forming areas of non-uniform turf quality. To help overcome dry patch, the use of wetting agents have now become an integral part of the maintenance regime, with applications being applied on a monthly basis throughout the summer.
Key Tasks for July
The condition of the court will certainly contribute to how well it performs, particularly with reference to ball bounce and foot adhesion. Ideally, you should be providing a true, firm and level surface that is both safe for the player whilst, at the same time, providing an adequate consistent ball bounce.
Foot traction/ball bounce can be affected by several factors:-
- Amount of organic matter (thatch) present in the surface
- Moisture content of the playing surface
- Condition of sward
- Insufficient court rolling
- Uneven levels/worn areas
- Type of footwear worn and condition of balls
Excess thatch content (more than 8mm) will affect playing quality by the mere fact that it becomes a spongy layer. This spongy layer deadens ball bounce and can cause poor foot traction - no grip. Control the build up of thatch by regular verticutting/grooming.
The level of moisture on or in the soil profile will affect how the court plays; a wet, firm surface will, in fact, speed up the pace of the ball. The use of covers will help control the wetness and condition of your courts.
The amount of grass cover on your courts will also dictate how the courts play. Too much grass, especially if over 10mm in length and over fed (applying too much nitrogen fertiliser) will, in turn, affect ball bounce and foot traction.
It is important to roll the courts to firm them up; rolling should be done during favourable weather conditions, ideally when the soil profile is malleable/moist enough to bind together.
It is important to monitor the condition of the court and constantly repair any bare and uneven levels. Topdress with compatible loam soils and overseed with a good quality ryegrass at a rate of 35-40 grams per m2.
It is also the players responsibility to ensure they are wearing appropriate footwear and using balls that are not damaged.
This month sees the continuation of regular maintenance tasks - grass cutting, grooming, brushing, aerating, feeding and watering. Particular attention should be made to your irrigation regimes, ensuring that all turf surfaces receive adequate amounts of water to maintain growth.
Groundstaff will also be trying to maintain the sward height at between 6-10mm depending on the level of play.
Mowing and Marking
The mowing height on the courts should be lowered to around 6-10mm for the playing season, subject to local weather conditions, but remember not to remove more than 1/3 of total grass height in each cut.
Mowing frequency will be dependant on a number of factors, grass growth, sward type, level or standard of facility, resources (staff and machinery) but, generally, it may vary from daily, in the case of Wimbledon, to two to three days a week, or even weekly, depending on resources available.
It is important to remove any weeds from the playing surface, as they can affect ball bounce and performance of the court. Weeds can be removed by hand, or controlled by application of chemicals, usually a broadleaf selective weed killer.
Grooming and verticutting are operations that remove unwanted side grass growth and reduce the amount of debris in the sward. These operations are carried out on a regular basis, often weekly or fortnightly, and providing you have sufficient watering facilities. These operations are completed in conjunction with your mowing regimes.
Marking is important, lines need to be clean, straight and accurate; ensure your marking machine is cleaned and serviced, checking that all the components are working properly. There is northing worse than using a marker that drips and produces poor line quality. It will reflect on your workmanship. Remember to use string lines for accuracy. Also invest in a good quality paint products, there are plenty to choose from that will suit your requirements and budget.
A programme of aeration can be considered to alleviate any compaction from recent play. However, this needs to be done with an appropriate aerator, something like the Hydrajet, Dryject or SISIS Javelin Aeraid, which are able to penetrate the hard clay soil profiles without causing surface disruption, thus allowing some much needed air exchange to promote a second phase of grass growth.
Fertiliser treatment and turf tonic can be continued in accordance with your annual programme. If you haven't got a fertiliser programme, have your soil tested; try an independent soil analysis company for an impartial set of results.
In recent years, we have seen a change in feeding habits in professional sport, with more groundsmen resorting to a more detailed feeding programme using a concoction of fertiliser products and soil conditioners to maintain plant health.
This has generally been achieved applying a range of different products in the form of granular and liquid forms.
We are now seeing granular products being used as base/slow release feeds and being topped up with a range of liquid feeds that include bio stimulants along with micro nutrients. To help improve the performance of these feeds, a number of soil additive products and wetting agents are in regular use.
However, for a majority of smaller clubs/facilities, they will be reliant on a trusted base fertiliser, a 12:0:9, 7:0:7 or similar compound blend, or apply a slow release fertiliser to see you through to August. The choice of material and how well it works will be dependant on factors such as soil type and weather, with moisture and soil temperature being the catalyst for growth.
The performance of slow release fertilisers can be influenced by the weather, often producing a flush of growth when you least expect it. Some grounds managers may use straight compound granular or liquid fertilisers which activate when in contact with moist soil conditions, effectively stimulating grass growth within days.
Please clink on the following link to read an interesting article on understanding NPK fertilisers by James Brierley
There is no such thing as maintenance free facilities, they all need a certain level of maintenance to keep them in good condition and safe for play.
Artificial grass systems (weekly) - Keep surface clean with regular sweeping and brushing. Remove any algae and moss from surface. Sand filled systems require regular brushing to maintain manufacturer's recommendations on sand levels and pile heights.
American Fast Dry courts (before/after games) - Keep surface clean, rolling to consolidate surface, levelling and brushing of fast dry materials, brushing to clean lines.
Clay courts (weekly) - Keep surface clean, regular sweeping and brushing to restore playing levels using SISIS Trulute or similar equipment. Topdress any hollows or damaged areas. Repaint lines.
Tarmacadam (weekly) - Keep surfaces clean, regular sweeping and brushing. Repair any hollows or damaged areas. Repaint lines.
Many groundsmen now undertake a number of testing procedures to assess their courts, generally these tend to be ball bounce and hardness.
Ball bounce is simple; measure the height of a rebounding ball dropped from a pre-determined height. Testing for hardness requires a specialist piece of equipment called the Clegg Hammer, which essentially consists of a hammer weighing 0.5kg to which an accelerometer is attached. The hammer was developed for testing soft materials, such as turf or sand and is ideal for testing sports surfaces such as golf greens, cricket pitches and tennis courts. This equipment can be hired from specialist suppliers. Recording and monitoring these two parameters will help you have a better understanding of how your courts are performing.
Many groundsman are now also using moisture meters to monitor soil moisture deficit (SMD); by keeping an eye on these losses, you can then apply the correct amount of water to replace the water lost by evaportransipration.
Keep an eye on fungal disease attack and use approved fungicides to treat infected areas. Outbreaks of Red thread may occur, which often indicates your grass is in need of a feed. Usually an application of a nitrogen feed will be enough to control an outbreak of Red thread.
It is important to remove any weeds from the playing surface as they can affect ball bounce and performance of the court. Weeds can be removed by hand or controlled by the application of chemicals, usually a broadleaf selective weed killer. Best results are achieved when the soil has warmed up and the grass is actively growing.
Keep machinery in good order, clean after use and top up any oil / fuel levels.
Check cutting cylinders are at correst cutting height and are sharp.
Pitchcare provide a range of courses suitable for tennis clubs. In most cases, the courses can be held on site using the club's own equipment and machinery.
Some of the courses available are:
- Chainsaws - CS30 and CS31
- H&S Refresher Training on Combined Turf Care Equipment; Tractors and Trailers; All Mowers (Ride-on and Pedestrian)
- Machinery Courses on ATVs; Tractors: Brushcutters/Strimmers; Mowers (ride-on and Pedestrian)
- Pesticide Application (PA courses)
- Stem Injection of Invasive Species (Japanese Knotweed etc.)
- Basic Trees Survey and Inspection
More details about all the courses can be found here, or you can email Chris Johnson for information.
Begin to plan your end of season renovations based on the condition of the courts. You may need to book specialist supplies and contractor services and ensure you buy compatible loam/soil dressings for your courts.