I already have HOA approval for a rectangular flower garden 4' by roughly 16' set 3' back from the driveway and sidewalk, also 12' from the house and 7' from the corner of the garage. I've already purchased or preordered the plants, some of which may not be best suited to a raingarden. However, I've had luck elsewhere as long as the plants were interspersed with others suited to wet to medium soil. The roof area is about 23 by 23. I planted a tree to the left of this picture. The soil is heavy clay. Drainage exceeded 24 hours. Thus, 23x23x.3= 160 feet rounding (a rain garden by 16'). The roof drains under the sidewalk out to the green area in the picture. I would start with the currently HOA-approved flower bed.

Here the plants I had already selected.

Closest to House

root moisture soil preference Plant Name height spacing

rhizome Dry Gravel, Sand Purple love grass 1'-2' 1'-2'

Rhizome Dry, Medium, Moist Clay, Loam Short-Toothed Mountain Mint 2'-3' 2'

Rhizome Medium, Moist Clay, Loam, Sand Beebalm (red) 3' 18"

Fibrous Moist, Wet Clay, Loam, Sand Swamp milkweed 4' 1' - 18"

Fibrous Dry, Medium Loam, Sand Prairie dropseed 2' 2'

Fibrous Medium Loam Royal Catchfly 2' 1'

Taproot Dry, Medium Clay, Loam, Sand Purple poppy mallow 1' 3'

Fibrous Dry, Medium Columbine 1' 1'

Rhizome Dry, Medium Loam, Sand Prairie smoke 6" 6"

Furthest from House - By sidewalk