Discussing others' designs is a way to focus on basics in our own work. It helps us develop better designs and solutions to problems.
We don't think there is any "right" or "wrong" in landscape design. It's art, a subjective medium meant to fulfill property owners' unique wishes and needs.
The landscapes we most often discuss are those that make us wonder what purpose was being served. As often, we come to the conclusion that the designer slipped up in identifying and fulfilling the owners' needs.
This garden is one of those. Thus we suspect its owner may be unaware the bed is overplanted, or what consequences overplanting can have. So our discussion of this bed included:
"When will realization dawn?"
"What will be left then that's salvageable?"
"How could we make the garden keep working from that point forward?"
To answer those questions, we needed to list what features of the bed a person would value, watch, and want to keep. We settled on these "keepers", here:
We think most of that can be saved if someone begins pruning, well, and soon. Or they can all be retained throughout the larger landscape if the bed is actually a holding bed.
Everything that's in the bed can stay if a gardener begins pruning next year to keep the plants small.
Delay could ruin this plan (below). If a person waits until the bed's obviously overgrown, it will be impractical to reclaim the evergreens. Even bringing the simplest shrub back into line -- the dwarf lilac -- will require extra time. (See Prune a dwarf lilac for the how-to.)
All but a few plants can be transplanted out of this bed over two to four years and used in other places in the landscape, such as creating a hedge from the dwarf lilacs (right; yup, those are the "dwarves."). They could be replaced with plants of similar design characteristic but smaller stature.