About Wimbledon - Information Sheets

Grass courts general information

Staff

Courts

17 Championships grass courts in total for 2010.
22 grass practice courts.
Courts are not floodlit as dew on the grass would make them too slippery for play.

Court Preparation

The courts are prepared in a similar manner each year to produce the highest quality playing surface for the world’s best players to display their full range of skills.
That means the courts must have even and consistent bounce, as well as the ability to withstand prolonged wear and tear for a minimum of 13 days.

Court Durability

Courts are sown with 100% Perennial Ryegrass (since 2001) to improve durability and strengthen the sward to withstand better the increasing wear of the modern game.
Independent expert research from The Sports Turf Research Institute in Yorkshire, UK, proved that changing the grass seed mix to 100% Perennial Ryegrass (previously 70% Rye/30% Creeping Red Fescue) would be the best way forward to combat wear and enhance court presentation and performance without affecting the perceived speed of the court.

The Grass

The grass plant itself has to survive in this dry soil. Expert research has again shown that a cut height of 8mm is the optimum for present day play and survival.
The height of cut has been at 8mm since 1995.

Speed of Courts

There has been no intention either this year or in previous years to produce slower courts or ones suited for a particular type of game.
Perceived speed of a court is affected by a number of factors such as the general compacting of the soil over time, as well as the weather before and during the event.

Bounce

The amount a ball bounces is largely determined by the soil, not the grass. The soil must be hard and dry to allow 13 days of play without damage to the court sub-surface.
To achieve the required surface of even consistency and hardness, the courts are rolled and covered to keep them dry and firm. Regular measurements are taken to monitor this.
If the court is too soft, when the players run, jump and slide, the pimples on their shoes will damage the surface and increase the chance of an irregular bounce.

The Effects of Atmospheric Conditions

Unlike other surfaces grass is a living plant in an outdoor environment when weather varies throughout the year. Weather conditions in the run up to The Championships will have some effect on the way the courts ultimately play.
The atmosphere can also have an effect on the ball which will seem heavier and slower on a cold damp day and conversely lighter and faster on a warm dry day.

The Ball

Specification of the ball was unchanged since 1995, when there was a minimal alteration in compression.
Balls are opened on court - the first set immediately before the match and thereafter just before each scheduled ball change.

Court Maintenance

Court grass composed of 100% rye grass (chosen for its durability).
1 tonne of grass seed is used each year.
Maximum of 3,000 gallons of water used during the Fortnight - weather permitting.
All courts re-lined, rolled and mown daily during Championships.
Court wear, surface hardness and ball rebound are all measured daily. In general, the men are tougher on the courts than the ladies.
The Championships playing height of grass is 8mm.
All courts renovated in September.

Hawk-Eye

Service Line Monitors

Lines

Paint is not used to mark the lines on the court. A transfer wheel marker is used to apply a white compound (500 gallons used yearly) containing china clay to make it durable.
All the lines are 50mm wide, except the baselines, which are 100mm.

Covers

All courts have been provided with covers since 1971.
Centre Court received a new cover in 1998. Weighs 1 ton (wet and dry) and takes 17 people approx 22-28 seconds to cover the court. Made from a translucent material, the cover allows a greater amount of light to the grass. Air ventilation under the cover is aided by four large fans (two at either end).
No.1 Court received a new cover in 1997 and 2010. Properties similar to that on Centre Court. Air ventilation is the same as Centre Court.
Extra fans provided on Courts 2, 11 and 18 to quicken the drying of the grass after rain.

Centre Court Roof

Design of the new fixed roof ensures that conditions for grass growth are better than those experienced with the old roof since the aperture is wider thus allowing more sunlight onto all parts of the court, particularly the southern end.

Court Coverers

160 Court Coverers.
Trained two weeks prior to The Championships.
Gradual training, which then builds up on the speed.
Safety is paramount, but speed essential - approx timings 22-28 seconds.
Pushing the umpire’s chair with umpire still in it introduced in 2001 for the first time.

Centre/No 1 teams

Outer Courts teams

Rain preparations

System of numbers used to alert and instruct the court coverers if rain or bad weather is expected:

Referee inspects a court once the covers are taken off and before the court is dressed with the net etc. Decision on timing of process made by the Head Groundsman or Referee.

Court Dimensions

Last Updated: 28 June 2010

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