Ground cover plants as mulch
To take over the function of the mulch squares by the shrubs and trees in the long run, we should plant ground-covering plants.
It seems logical to plant these on/ through the mulch. However, some of the trees are very small when they are first planted, and grow slow. If we plant the ground-covering plants directly by the trees, the trees might well have to compete with the groundcover plants.
Another problem is that many of the ground covering plants spread by means of over or shallow underground roots being sent out. This is not going to work on the mulch fabric or on the woodchips, as its purpose is to keep plants from growing through it.
The best way to deal with this is to plant the ground-covering plants around the mulch. This way they are likely to be the first plants to grow in the area where the mulch is starting to decompose.
Until then they give the trees and shrubs some space, so they can establish and get a good start growing.
Around the smaller shrubs (fruit bushes) we can sow annual groundcovers (next to the mulch), and later transplant some of the ground-covering plants from the trees, once those have spread.Although we could use the perennial ground covering plants, using annuals at first could help keep costs of plants down.
Under the hedges, we don’t need to make use of a mulch. Many of the species best suited for growing under the hedge are easy to establish as seed, but seed cannot be sown on top of the mulch. As hedge plants are quite strong, it is easier not to use a mulch, provided we give them an extra layer of compost and sow the area with hedgerow plants as well as planting some plants like ivy, periwinkle and wild strawberries to keep the ground covered.