When you need to join grass together to cover a whole area the best way to do this is with joining tape. We recommend putting grass in position first then putting the tape under the join with half under each side of the grass you are joining. Slowly peel the plastic off to reveal the tape and push the grass back down on to the tape, knitting together as you go. Press down hard. After this we recommend applying U nails every 300mm over the two joins. This products instantly sticks and is a permanent solution.
We recommend this tape as used on our previous projects as we have found the backing comes off easily, making the job easier. Some others we have used in the past come off in little bits and do not adhere well……. we learnt the hard way.