| | | | |
| A | Genus | Species | Cultivar | Common Name |
 | ABUTILON | | 'Savitzii' | AGM |
| ACAENA | affinis | | |
| ACHILLEA | | 'Anthea' | |
| ACHILLEA | | 'Credo' | AGM |
| ACHILLEA | | 'Fanal' | |
| ACHILLEA | | 'Inca Gold' | |
| ACHILLEA | | 'Lachsschonheit' | Syn. A.'Salmon Beauty' |
| ACHILLEA | | 'Martina' | AGM |
| ACHILLEA | | 'Mondpagode' | AGM |
| ACHILLEA | | 'Moonshine' | AGM |
| ACHILLEA | | 'Red Velvet' | |
| ACHILLEA | | 'Rose Madder' | |
| ACHILLEA | | 'Summerwine' | AGM |
| ACHILLEA | | 'Terracotta' | |
| ACHILLEA | | 'Walther Funcke' | |
| ACHILLEA | ageratum | 'W.B.Childs' | |
| ACHILLEA | fraasii | | |
| ACHILLEA | millefolium | 'Cerise Queen' | |
| ACHILLEA | millefolium | 'Paprika' | |
| ACONITUM | | 'Bressingham Spire' | AGM Monkshood |
| ACONITUM | | 'Ivorine' | |
| ACONITUM | carmichaelii | 'Arendsii' | AGM |
| ACONITUM | carmichaelii | Wilsonii Group | |
| ACONITUM | carmichaelii | Wilsonii Group 'Kelmscott' | AGM |
| ACONITUM | carmichaelii | Wilsonii Group 'Spatlese' | |
| ACONITUM | lycoctomum | | Wolf's Bane |
| ACONITUM | napellus | | |
| ACONITUM | napellus subsp.napellus | Anglicum Group | syn. A.anglicum |
| ACORUS | calamus | 'Variegatus' | Sweet Flag or Myrtle Flag |
| ACTAEA | rubra | | AGM |
| ADIANTUM | venustum | | AGM Maidenhair Fern |
| AGAPANTHUS | | 'Black Budda' | syn. A. 'Black Buddhist' |
| AGAPANTHUS | | 'Blue Moon' | |
| AGAPANTHUS | | 'Dokter Brouwer' | |
| AGAPANTHUS | | 'Navy Blue' | syn. A.'Midnight Blue' |
| AGAPANTHUS | | 'Purple Cloud' | |
| AGAPANTHUS | | 'Sunfield' | |
| AGAPANTHUS | | 'Windsor Grey' | |
| AGASTACHE | | 'Black Adder' | |
| AGASTACHE | foeniculum | (Pursh) Kuntze | Anise Hyssop. syn A.anisata |
| AJUGA | reptans | 'Black Scallop' | |
| AJUGA | reptans | 'Braunherz' | |
| AJUGA | reptans | 'Catlin's Giant' | AGM |
| AJUGA | reptans | 'Multicolor' | Syn. A.reptans 'Rainbow' |
| AKEBIA | quinata | | |
| ALCEA | ficifolia | | |
| ALCEA | rugosa | | |
| ALCEA | x kitaibela | 'Parkallee' | |
| ALCHEMILLA | alpina | | |
| ALCHEMILLA | erythropoda | | |
| ALCHEMILLA | mollis | | AGM Lady's Mantle |
| ALLIUM | aflatunense | | |
| ALLIUM | caeruleum | | AGM |
| ALLIUM | cristophii | | AGM syn. A. albopilosum |
| ALLIUM | hollandicum | 'Purple Sensation' | AGM |
| ALLIUM | karataviense | | AGM |
| ALLIUM | neapolitanum | | |
| ALLIUM | schoenoprasum | | Chives |
| ALLIUM | sphaerocephalon | | Drumstick Chives |
| ALLIUM | vineale | 'Hair' | |
| ALOYSIA | triphylla | | AGM Lemon Verbena syn. Lippia citriodora |
| ALSTROEMERIA | psittacina | | |
| AMICIA | zygomeris | | |
| AMSONIA | orientalis | | |
| AMSONIA | tabernaemontana | | |
| ANAPHALIS | margaritacea | var. yedoensis | AGM |
| ANAPHALIS | nepalensis var. | monocephala | Syn. A. nubigena |
| ANAPHALIS | triplinervis | | AGM Pearl Everlasting |
| ANAPHALIS | triplinervis | 'Sommerschnee' | AGM |
| ANCHUSA | azurea | 'Loddon Royalist' | AGM |
| ANEMANTHELE | lessoniana | | syn. Stipa arundinacea. Pheasant's Tail Grass |
| ANEMONE | multifida | | |
| ANEMONE | nemorosa | | |
| ANEMONE | nemorosa | 'Alba' | |
| ANEMONE | nemorosa | 'Pentre Pink' | |
| ANEMONE | nemorosa | 'Robinsoniana' | PROJECT ANEMONE |
| ANEMONE | nemorosa | 'Vestal' | PROJECT ANEMONE |
| ANEMONE | x hybrida | 'Honorine Jobert' | AGM Japanese Anemone |
| ANEMONE | x hybrida | 'Konigin Charlotte' | AGM Syn. A.'Queen C.' |
| ANEMONE | x hybrida | 'Whirlwind' | (H&K) |
| ANEMONE | x lipsiensis | | |
| ANGELICA | archangelica | | Angelica |
| ANGELICA | gigas | | |
| ANISODONTEA | capensis | | |
| ANOMATHECA | laxa | | AGM |
| ANTHEMIS | tinctoria | 'E.C. Buxton' | Dyer's Chamomile |
| ANTHEMIS | tinctoria | 'Sauce Hollandaise' | |
| ANTHERICUM | liliago | | St. Bernard's Lily |
| ANTHRISCUS | sylvestris | 'Ravenswing' | |
| ANTIRRHINUM | molle | | |
| ARABIS | alpina | rosea | |
| ARABIS | ferdinandi-coburgi | 'Old Gold' | |
| ARGYRANTHEMUM | | 'Mrs F. Sander' | |
| ARGYRANTHEMUM | | 'Summer Cloud' | |
| ARGYRANTHEMUM | gracile | 'Chelsea Girl' | AGM |
| ARISTEA | ecklonii | | |
| ARISTEA | major | | |
| ARMERIA | maritima | 'Alba' | Ladies' Cushion |
| ARMERIA | maritima | 'Dusseldorfer Stolz'' | |
| ARTEMISIA | | 'Powis Castle' | AGM |
| ARTEMISIA | abrotanum | | AGM Southernwood |
| ARTEMISIA | lactiflora | Guizhou Group | |
| ARTEMISIA | schmidtiana | 'Nana' | AGM |
| ARTEMISIA | stelleriana | | Dusty Miller |
| ARTEMISIA | stelleriana | 'Boughton Silver' | |
| ARUM | italicum subsp.italicum | 'Marmoratum' | yn.A.i.'Pictum' Lords and Ladies |
| ARUNCUS | dioicus | | Goat's Beard syn A. sylvester |
| ARUNCUS | dioicus | 'Kneiffii' | |
| ASARUM | naniflorum | 'Eco Decor' | |
| ASPHODELINE | lutea | | King's Spear |
| ASPLENIUM | scolopendrium | | AGM Hart's Tongue Fern |
| ASTER | | 'Coombe Fishacre' | AGM |
| ASTER | | 'Ringdove' (ericoides hybrid) | AGM |
| ASTER | amellus | 'King George' | AGM |
| ASTER | amellus | 'Rosa Erfullung' | syn. A. amellus 'Pink Zenith' |
| ASTER | amellus | 'September' | (name unknown) |
| ASTER | cordifolius hybrid | 'Little Carlow' | AGM |
| ASTER | divaricatus | | syn. A.corymbosus |
| ASTER | ericoides | | |
| ASTER | laevis | 'Calliope' | |
| ASTER | lateriflorus | var. horizontalis | AGM |
| ASTER | novae-angliae | 'Andenken an Alma Potschke' | |
| ASTER | novae-angliae | 'Barr's Pink' | |
| ASTER | novae-angliae | 'Herbstschee' | syn.A.n-a.'Autumn Snow' |
| ASTER | novae-angliae | 'Purple Dome' | |
| ASTER | novi-belgii | 'Winston S. Churchill' | |
| ASTER | x frikartii | 'Monch' | |
| ASTER | x frikartii | 'Wunder von Stafa' | AGM |
| ASTILBE | | 'Montgomery' (japonica hybrid) | |
| ASTILBE | | 'Sprite' (simplicifolia hybrid) | AGM |
| ASTILBE | | 'Venus' (x arendsii) | |
| ASTILBE | chinensis var. pumila | | AGM |
| ASTRANTIA | | 'Buckland' | |
| ASTRANTIA | | 'Hadspen Blood' | |
| ASTRANTIA | major | | |
| ASTRANTIA | major | 'Claret' | |
| ASTRANTIA | major | 'Roma' | |
| ASTRANTIA | major | 'Ruby Wedding' | |
| ASTRANTIA | major alba | | |
| ASTRANTIA | major subsp.involucrata | 'Moira Reid' | |
| ASTRANTIA | major subsp.involucrata | 'Shaggy' | Coton DIVISIONS/MAY REVERT FOR A WHILE |
| ASTRANTIA | major var.rosea | | |
| ASTRANTIA | maxima | | AGM |