As we approach summer the shelf life of turf reduces dramatically. Turf starts to deteriorate as soon as it is rolled up and it is crucial to get the turf laid and watered as soon as it arrives. If the turf is left rolled up the turf starts to heat up. This heating is caused by micro-organisms present in soil that breathe or consume the oxygen. As the supply of oxygen depletes other organisms that need very little oxygen become active. As they start growing they generate heat just like in a compost heap. You may have noticed that grass leaves or hay, when piled up, become hot and may even look like they are smoking.
The same type of heat generation goes on in rolled up turf. The rolled up turf acts like a blanket, it traps this heat. The rolled up turf cannot cool itself, because there is no oxygen and the heat cannot escape very fast. Therefore, the turf becomes hot. At first the heat will cause the grass to turn yellow. This may happen within 24 – 48 hours after the turf is harvested. If the turf remains rolled up the heat will continue to build up and the turf will go black, mold will appear and eventually the turf will die.
To help keep it fresh arrange for it to be placed in the shade. Split the stacks to allow the turf at the centre of the stack (where it is hottest) to cool down. Don’t be tempted to water the turf whilst it is rolled as the moisture will cause the turf to deteriorate faster.
If the turf has started to yellow then it is okay to lay and should recover within a few days once laid and watered. However, if the turf is starting to go mouldy or if the grass has turned a blackish colour with a slimy film on the grass it has been left rolled up too long and it is very unlikely to recover.
If you are worried about laying turf in hot weather if you exercise a few precautions you will have good results.
- Order the turf to be delivered on the day you intend to lay it, if you are ordering a large amount schedule an earlier delivery.
- If possible make sure the turf is placed out of direct sunlight
- Don’t water the turf while it is still rolled up
- Split the turf stacks in half to allow the centre of the stack to cool
- Start laying the turf immediately
- Set the sprinkler to water the turf as it is being laid
- It is advisable to order at least 5% over and above what you need in case some of the rolls have over heated in transit.