We have a very very old ginkgo tree on our property. Supposedly, it was given to Zachary Taylor by the Japanese Ambassador at the time. It is situated in a very large horseshoe area next to our house. With that area, we inherited lots of liriope, hostas and a few bulbs.

The weeds in this horseshoe area are incredible. If left unattended, they will grow to waist level and beyond twice a year. We tried Preen in fall and spring to no avail. Then we finally figured out that the ginkgo balls are germinating everywhere and hence the weeds. BTW, they also smell.

What would you recommend for this area? Since it is large, mulching it 3 inches would be pretty cost prohibitive.