I planted dune grass in my yard, which is a dune overlooking Lake Michigan. Do I need to rake the thatch in the spring? The new growth is beginning. Do I leave it alone (I planted it 6 years ago), and it fills in beautifully in the summer. I have gotten so many different opinions, so I am confused. Should I fertilize? Also, I have lots of weeds, which I pull but I can't keep up! Can I apply a broad spectrum weed killer? Please help - we love our dune grass and want to take care of it properly. Thank you. Anne Harris
What kind of dune grass do you have (switchgrass, beachgrass, etc.) and how large an area of it do you have? Do you cut it back every year? The decision to remove thatch really depends on how thick the thatch is. If it's over 1/2 inch it could be too much of a barrier for water and nutrients getting into the soil, otherwise I would probably leave it alone. The use of a thatching rake is recommended, but it is best to rake before the onset of new growth.
As for weed control, you will probably want to investigate the use of a pre-emergent herbicide.
https://www.gardeningknowhow.com/plant-problems/weeds/pre-emergent-herbicides.htm