Some people go to a lot of trouble and expense to create walls in their gardens and yards. An ugly cement wall can act as a solar sink to give off heat to tender plants. Walls can be wind buffers and privacy screens as well. With some clever transformation, your ugly cement block wall may become your favourite part of the yard.
If your wall faces south, attach closed eye bolts to that face of the wall at 2-foot intervals from top to bottom and every 5 feet or so along the wall. (Use a masonry bit to drill out holes for the bolts, and set them in hydraulic cement inside the holes.) Run heavy stainless steel wires through the eyes across the wall, and use them to train espaliered fruit trees against the wall. The extra heat generated by the sun heating the masonry surface will allow more tender trees to do well in generally harsher climates and give an early boost to ripening fruits.
Anchor eye bolts in place as above, but use them as points to secure wooden lattice to the wall a couple of inches from the surface. Allow climbing roses, clematis or other flowering vines to climb the trellis. If you prefer to use the space for vegetable production, cucumbers, squashes, peas and beans are other good candidates for trellis growing.
If you are not into gardening, or have a hopelessly shady wall, paint a mural on it. If you are not artistic yourself, you can hire a local artist or paint something purely abstract that requires little technical skill and incorporates lots of fun colour. If you are skilled, try creating a trompe-l'oeil or “fool the eye” design, incorporating a pretend view or fake plants to make your wall disappear into the landscape.
If none of the above are practical or appealing, consider buying face bricks or fake stone in thin sections to glue a brand new face on that ugly block wall. In only a few days, using little more than mortar and trowel, you can create the look of an old stone or brick wall to match your home or add a touch of class to the landscape.
Paint the wall in a bold colour and attach a bas-relief scupture, wall fountain, large framed mirror or individual potted plants in wall hangers (or anything else you find appealing). Mix and match to create an artsy, architectural “montage” of living and inanimate objects to decorate your environment.