I think the code word for the flaw in your landscaping is probably "amorphous." The plants you name are all perennials; they are basically masses of flowers on sticks; their overall shape is (a) similar and (b) blobby. That they are little is not the problem; rather, they simply have no features that are apparent from a distance. No matter how established these plants get, they are not going to develop a more interesting shape.

From a plant selection point of view you want form and structure - a weeping dark beech for example, or other shrub, and it doesn't have to replace the plants you have but will give them a focal point. In the perennial family I'd also look at plants that have big, bold foliage (not sure what's hardy for you, but like Acanthus, Hostas, Ligularias, Crambe maritima, and others.

I'm also wondering if hardscape would help. A more solid fence or hedge might provide better background, and you don't say how the border is edged, but an edge you can see from the distance would be an important element of the design.

I'm guessing you only sit on the deck in summer, but if you want the border to look nice year round, some evergreen shapes might also enhance it. Or some Japanese maples with splendid spring or fall colour?

KarinL

You know, I forgot at the end of the season I planted two Iceberg rose bushes and two Black Lace shrubs. I hope these help but I think I may have to write off the the Black Lace as they were looking super weak at the end of the season. When you said flowers on sticks I think it flipped a switch in me - "yep, that's it". I didn't notice it before but I think I will divide some hostas from my shade garden and incorporate them into this one. Plus, I may add some ornamental grass. Thanks for getting my brain going. Another problem I think is too many colours because the cosmos and zinnias were multicoloured.

To see things at a distance more clearly, it helps if those things are very large.

Think masses of similar plants and larger plants that occupy space. Those will be seen from a distance. Also a wavey bed is great for a close up view of the garden, but is not a bold bed shape when viewed as a whole from a distance. A wavey shape would be more disruptive. Think of a concave or other organic shape that has substance from one end of the bed to another. Even geometric design formal design if applied to the whole would add unity to your overall view.

You are already on the right track with your thoughts of adding the Hostas and perennial grasses for foliage texture and contrast, and your thoughts to use non-mixed colors for the zinnias and cosmos to give more impact this summer. Planting the annuals in larger drifts all of a kind will also help them "read" from a distance. You didn't mention if you are also wanting more structure over the whole year, but I would think that adding some hardy shrubs with winter interest could also help, such as some of the colored stem selections of Dogwoods/Cornus sericea/stolonifera, or srping blooming deciduous shrubs such as Weigelia, Spirea, etc.

Repetition of forms, colors and quantities across the border will also help it read better from a distance.