Measure your flower bed with a measuring tape. Cut your erosion control blanket 1 inch larger than your measurements on each side.
Dig a 3-inch deep trench around the perimeter of your flower bed with a trowel. Place the edge of the erosion control blanket into the trench, folding the edge under itself as you go and securing it in place with landscaping staples. Landscaping staples are U-shaped wire staples that you push through the blanket and into the soil by hand, securing the edging and helping to hold the blanket in place. Fill the trench back in with soil.
Plant flowers in the bed by cutting holes in the erosion blanket big enough to fit the base of the plant.
Cover the entire surface of the flower bed with 2 inches of mulch. This will secure the bed and protect it from erosion while the plants become established.