- Daisy fleabane
- Dakota mock vervain
- Dallis grass
- Dame's rocket
- Dark Mullein
- Dark-red Helleborine
- Dark-throated shooting star
- Dead Man's Fingers
- Deadly Nightshade
- Deer fern
- Deertongue
- Deerweed
- Deptford pink
- Desert agave
- Desert Broom
- Desert ironwood
- Desert lavender
- Desert lily
- Desert Paintbrush
- Desert Sunflower
- Desert tobacco
- Desert Trumpet
- Desert willow
- Devil's Beggarticks
- Devil's Club
- Devil's walkingstick
- Devil's-bit Scabious
- Diamond-flowers
- Diffuseflowered Forget-Me-Not
- Distant phacelia
- Dog-rose
- Dog's Mercury
- Dogfennel
- Dot-seed plantain
- Dotted gayfeather
- Dotted Loosestrife
- Douglas iris
- Douglas-fir
- Dove's-foot crane's-bill
- Downy Birch
- Downy rattlesnake plantain
- Dropwort
- Drummond's rain lily
- Durban Crowfoot
- Dusky Crane's-bill
- Dutchman's breeches
- Dwarf crested iris
- Dwarf Elder
- Dwarf Everlasting
- Dwarf Fireweed
- Dwarf ginseng
- Dwarf horsetail
- Dwarf Iris
- Dwarf larkspur
- Dwarf mallow
- Dwarf Nettle
- Dwarf Palmetto
- Dwarf raspberry
- Dyer's Greenweed