As we move to the right, the bed is increasingly shaded by a high deciduous tree (visible next to hideous white pipe) from early May on. This provides afternoon (and even mid-day) shade, with shading beginning earlier in the day the farther one moves to the right, providing a good bed for bleeding heart (Dicentra spectabilis), the longer-blooming fringed bleeding heart (D. eximia), Astilbe, and, since the photo was taken, a variegated Hosta last fall and a Primula just a week ago (a Home Depot $0.99 special). The bleeding hearts were freebies from my neighbor, and remained healthy despite moving with limited root structures and despite my delay in getting some of them in the ground.
I credit the soil.
This far right-hand section of the bed was actually the worst I have dug, with compacted clay and rocks making up the bulk of the “soil.” After using the mattock and shoveling out clay and rocks, I amended it most heavily, adding leaf mold, wetted peat moss and local soil in mid-May, just a day before planting. “Aging” the bed was not necessary due to my avoiding incompletely composted materials. Despite some fear of a bathtub effect, I’ve seen no signs of sluggish drainage; the site’s raised location apparently makes up for its being surrounded by packed clay.
The afternoon shade allowed my spiderwort (Tradescantia) to keep its delicate blue-purple flowers open all day (they more typically close up at noon), yet the full morning sun is enough to keep pink Cleome and red Cosmos happily flowering behind it, if a bit leggy. The red grass at left (a non-hardy Pennisetum, I believe) also grew tremendously, but the lavender in the left foreground wants more grit and sun, and the barely noticeable Verbena to the immediate right of the Tradescantia suffered from powdery mildew. This mildew was endemic to the brambles (Rosa multiflora, blackberry, and something else with 5-leaf clusters and thorns) which dominated the aqueduct slope behind until I ripped and cut them all out last fall (some visible to left of Cleome in this photo), leaving behind established clumps of goldenrod (Solidago).