January 31, 2012
My name is Tom, also known as HD116 at Home Depot's How to Community. I am here today answering a few product questions. I saw yours and realized it had gone unanswered for quite some time.
The netless seed mats are designed for use on slopes and difficult terrain to establish seed. They absorb moisture which is critical in germination and establishing new growth. The excess moisture combined with the density of the fabric may actually cause problems with the existing grass in terms of lack of sunlight and danger of fungus forming. The fact that the seed would not be in contact with the soil to allow for the roots to establish due to the existing grass is also a factor.
All things considered, I cannot recommend this product on established grass. Thank you for your question and I hope that helps.
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