Finish this type of trench lawn edging by covering the area with some type of mulch. A mulch layer helps keep weeds from sprouting in the uncovered soil and prevents soil erosion from the planting bed itself. If your trench area is shallow, you can run your lawn mower along the bed edge by dropping one wheel into the trench. This eliminates any need for string trimming the lawn edge.
Rather than fill the empty space of the planting beds with an array of flowers and shrubs, the designer chose to emphasize the unique boxwood shapes by planting them far apart. A simple, neat layer of mulch ensures the focus remains on the artistic topiary element and deters the growth of weeds.
Fall’s classic bloomer is the garden mum. These colorful beauties paint the autumn landscape in nearly any shade imaginable, from pastel tints to bold hues. Garden mums grow best in full sun with well-drained soil and work well in containers or beds. To enjoy the longest show, choose mums with flower buds that are just beginning to crack open. To overwinter plants as perennials in colder zones, get mums into the ground as early as possible in fall. Mulch well after the ground freezes. Plants grow 1 to 3 feet tall and wide. Hardy in Zones 5-9.
Killing actual dandelion plants is one tactic in the war on this weed. Another is creating an environment where dandelion seeds can’t successfully germinate. To do this, use a pre-emergent herbicide like corn gluten meal or Preen. This type of weedkiller interferes with seed germination, which means seeds can’t produce a plant. Use corn gluten meal in fall and early spring (about the time forsythia flowers). Another technique to make your yard unfriendly to dandelion seeds is to mulch planting beds, and don’t cut your lawn shorter than 2 to 3 inches. Taller grass grows thicker, shading soil so dandelion seeds can’t sprout.