If you want to brighten the blank face of a wall with flowers and foliage there are many shrubs to choose from that will make an attractive enhancement. You can either cover the wall with a climbing variety or choose a shrub that can be planted in front of the wall to create an attractive screen. You can also consider using a large host plant that's already established and adding a second plant to intertwine through its stems.
Several factors should influence your choice of plant. Think about the dimensions of the area of the wall to be covered, the ultimate height the plant may reach, and how the color of any flowers combines with other plantings in your yard. You also need to consider whether your plant of choice likes a sunny or shady aspect, and what sort of soil it requires to thrive.
