'Arbuscula' Shrubby Cinquefoil Arbutus, Trailing
'Arcadia' Savin Juniper 'Arch McKean' Lilac
Archangel Archangel, Yellow (spp.)
Archangel, Yellow 'Florentinum' Archangel, Yellow 'Herman's Pride'
Archangel, Yellow Variegated 'Archer's Gold' Lemon-Scented Thyme
'Arctic Beauty' Kiwi Arctic Bramble
'Arctic Fire' Maiden Pink 'Arctic Fire™' Red Osier Dogwood
'Arctic Fury' Tall Bearded German Iris 'Arctic Glow' Globe Thistle
Arctic Polemonium 'Heavenly Habit' Arctic Poppy (spp.)
Arctic Poppy 'Champagne Bubbles' Arctic Poppy 'Wonderland Mix'
'Arctic Summer' Silver Mullein Areca Palm
Arend's Phlox 'Anja' Arend's Saxifrage 'Triumph'
'Argent' Mealycup Sage 'Argentea' Colorado Spruce
'Argentea Compacta' Scots Pine 'Argentea Marginata' English Holly
'Argentea' Pagoda Dogwood 'Argentea' White Fir
'Argenteo' English Holly 'Argenteo-Marginata' White Dogwood
'Argenteomarginatum' Japanese Maple 'Argenteus' Garden Thyme
Argentine Blue-eyed Grass Argentine Mesquite (spp.)
Argentine Mesquite 'Colorado' Argentine Rain Lily (spp.)
Argentine Rain Lily 'Russell Manning' Argyranthemum
'Ariake nomura' Japanese Maple Arikury Palm
Aristea 'Aristocrat' Daylily
'Aristocrat' Hosta 'Aristocrat™' Callery Pear
Arizona Ash Arizona Ash: velutina
Arizona Blue Star Arizona Cypress (spp.)
Arizona Cypress 'Blue Pyramid' Arizona Cypress 'Golden Pyramid'
Arizona Cypress: arizonica arizonica Arizona Mesquite
Arizona Rosewood Arizona Sliprod
'Arizona Sun' Blanket Flower Arizona Sycamore
Arizona Walnut Arizona Yucca
Arkwright's Campion 'Orange Gnome' Arkwright's Campion 'Vesuvius'
Arkwright's Catchfly 'Orange Gnome' Arkwright's Catchfly 'Vesuvius'
'Armande' Rose of Sharon Armenian Geranium (spp.)
Armenian Geranium 'Bressingham Flair' 'Armstrong' Freeman Maple
'Armstrong II' Freeman Maple 'Arneson Cameo' Azalea
'Arneson Flame' Azalea 'Arneson Gem' Azalea
Arnica, Leafy 'Arnold dwarf' Norway Spruce
'Arnold' Tulip Tree 'Arnold's Promise' Witchhazel: intermediahybrid
Aroid Palm Arolla Pine (spp.)
Arolla Pine Dwarf Arolla Pine 'Pygmaea'
'Aromas' Spider Flower Aromatic Ginger
Aronia, Black Berried 'Low Scape® Mound' Aronia, Black Berried 'Viking'
'Arp' Rosemary Arrayan