In answer to the original question the pitch will be fed and probably quite frequently. Due to the open and sandy structures of modern sports turf root zones (soil) which facilitate efficient drainage, water percolation quickly flushes the nutrients out in a process called leaching. It is likely that a high proportion of magnesium and iron will be included to give the dark colour as well as provide some protection against fungal diseases which can be a problem in stadia due to poor air movement. A balanced feed for sports turf will provide an NPK value of something like 12:0:20 – NPK being Nitrogen, Phosphorous and Potassium which are the chemical elements that form the primary sources of food for all plants.
Nitrogen is primarily for leaf growth and vigour and Potassium root development and cell health. Phosphorous is typically low in turf foods as it is generally associated with flowering and fruit development neither of which are required. Many areas of the industry are also moving towards organic based fertilisers derived from composted manure or sugar based components such as molasses which are not only more sustainable but also contain lower salt indexes which has benefits to the micro organisms in the soil which the grass plants also require.
The fibre reinforcing is the Desso system which was also installed into Wembley and has lead to the improvements in that pitch.
Another significant trick employed by the modern Groundsperson within the last five years is the use of a growth regulator called Primo Maxx. This basically checks the vigour of the top growth, i.e. the leaves; and redirects the energy into the root systems. This leads to better drought tolerance as well as more vigorous lateral spreading. The benefit of this is thicker grass and a more stable and hard wearing surface.
Finally the primary component of sports turf pitches in the UK is Perennial Rye Grass. It is used in its refined amenity forms as opposed to its rough and ready agricultural varieties. Whilst rye grass is hard wearing one of its limitations is that it is tufted which means it does not sent out any lateral runners, like you might see shooting off a strawberry plant. City however are engaged with Barenbrug a seed company who have bread a new type of rye grass called regenerating perennial rye grass which does have the runner habit. This will lead to even more hard wearing and thicker surfaces.
The following is from the Pitchcare Website;
Manchester City Football Club's award-winning grounds team has spoken about how specialist grass seed breeder Barenbrug is helping the Premier League club remain at the cutting edge of playing surface solutions.
Fresh from stadium head groundsman Lee Jackson leading the team to victory in the Barclays Premier League Groundsman of the Year Award, the team has embarked on an exciting new Barenbrug trials programme across its Carrington Training Ground and Platt Lane Academy sites.
The highlight of the programme is the UK's first trial of breakthrough product, Regenerating Perennial Ryegrass (RPR). Combining a unique creeping growth habit with the capability to establish quickly and tolerate wear, RPR creeping perennial ryegrass promises to be of great benefit for football, rugby and other sports surface applications - with the recent FA Cup-winning club a trailblazer in experiencing RPR's exciting attributes.
Platt Lane Academy was the first to establish the RPR trial on its fibresand constructed pitch. Head groundsman Steve Malone says that the RPR has done remarkably well since sowing on 11 May. "It has come through really well," he reveals. "The plant's looking very healthy, with a great colour and strong leaf that's already filling in at the base. I'm looking forward to seeing how it fares when we start training on it mid-July - we're particularly hoping it will provide improved winter wear and recovery. I'm very happy with it - it's great to try these things."
Over at Carrington, meanwhile, head groundsman Lee Metcalfe is equally pleased with the progress of his RPR trial pitch, sown 3 June on Loksand. "The RPR has germinated already," he says. "We're keen to see how it performs and how quickly it re-grows under the intensive wear pressure of the first team training when we start using it in August. It's exciting to trial something that could be the future of football grass seed solutions."
Likewise, this is part of a wider Carrington trial which includes future potential formulations of BAR 7, RPR and SOS. "It's a great privilege to be asked to take part in trialling new products," Lee continues. "The Man City grounds team is excited to see the results and continue to work with Jayne [Leyland, Barenbrug research and development manager] to identify products that will not only benefit our club, but others into the future."
The trial at Manchester City is a natural progression following the proven success of BAR 7 on different rootzones and constructions, including Fibresand and Desso Grassmaster at Platt Lane, and fibre rootzone (including undersoil heating), Fibresand and Loksand at Carrington. Eastlands Stadium's Desso pitch has also recently been sown with a special BAR 7 blend to minimise the incidence of the severe Leaf Spot disease pressures encountered in the stadium environment. What's more, BAR 7 has been chosen for the new Fibrelastic pitch currently being installed at Carrington.