Ya'll are funny and I don't mean to be rude here. But, if a root can break concrete apart, I don't think the netting is slowing them down. Now the biodegradability of them is no good... but there are articles on how to make you're own with cheese cloth.
Making Your Own Peat Pellets
This DIY can easily be substituted with coco.
Making Your Own Peat Pellets
This DIY can easily be substituted with coco.