Overseeding, chitting and sheeting - Understanding the terminology and methods 1OOC.
Overseeding worn and bare areas on sports pitches is an essential maintenance regime to ensure the upkeep of a healthy grass sward. Successful seed germination will be determined by a number of factors; weather and ground conditions at the time of sowing, methods used to sow the seed and, finally, the choice and quality of seed used.
It is important to use viable seed that is certified and from recent fresh stocks. Use cultivars that suit your requirements e.g. cricket, football, rugby.
Sow during optimum conditions when soil and air temperatures are consistently above 1OOC. Grass seed will usually germinate between seven to fourteen days.
However, seed establishment can be achieved much more quickly with the aid of germination sheets or when using pre-germinated grass seed.
This latter method is known as chitting. Soak the required amount of seed needed in a bucket of water for three to four days. The seed can be loose, but it is better to put in either a small jute sack or in a pair of ladies tights.
Tie a knot in the top of the tights, first ensuring your wife or partner is not still wearing them!
Place the bucket in a dark, warm room (such as an airing cupboard) and leave until the seed begins to germinate, showing small white tips. Then mix with some soil/sand or rootzone and brush into the area you have prepared for seeding.
Another method is to pre-mix seed with a dampened carrier of either sand or soil rootzone mix in a container until the seed germinates. Then use to repair worn and damaged areas.
Once you have repaired the bare areas, you will need to ensure the seed is not allowed to dry out and die. Keep the newly sown areas moist by covering with germination sheets or watering until the seed has established.
One of the biggest concerns for many is getting the pitches back into play after reseeding. Whether it is during in season repairs or after end of season renovations, it is important to get the seed to germinate as quickly as possible.
Seed sown during favourable soil/air temperatures (above 10OC) will germinate anything between seven to fourteen days. However, under the cover of a germination sheet, these times can be reduced to five to seven days, and even quicker if the seed has been chitted.
A germination sheet is simply a sheet that is used to cover and protects the newly seeded areas, creating a greenhouse environment, which often raises the air temperature under the sheet by two or three degrees whilst, at the same time, stopping any physical damage by birds and animals.
Horticulturalists and farmers have been using fleeces and plastic sheeting to speed up the germination and maturity of their crops for many years.
Germination sheets come in many different guises; hessian matting, plastic sheets, canvas sheets, wind break netting etc. Bespoke sheets to suit individual requirements are also available from various manufacturers and suppliers.
Depending on the desired results, the use of sheets vary. Some may leave them on overnight and take them off during the day but, in the main, most groundsmen and greenkeepers will leave them down until the seed has germinated and showing signs of growth.
In short, germination sheets save on seed and labour, speed up germination (which, in turn, produces faster growth), bring worn pitches back into use quicker, extend reseeding periods, give uniform and even coverage and protects seed from weed contamination, wind, birds, frost and scorching by the sun.