| Name | Kanji | Type | Photo | Year Registered |
| ‘Aaron Cook’ | Stewart | Yes | ||
| ‘Achievement’ | ||||
| ‘Acrobat’ | Glenn Dale | Yes | 1948 | |
| ‘Addy Wery’ | obtusum | Yes | 1940 | |
| ‘Ademurasaki’ | 艶紫 | Hirado | ||
| ‘Ademurasaki’ | 艶紫 | Kurume | Yes | |
| ‘Adesugata’ | 艶姿 | satsuki | ||
| ‘Admiration’ | Azalea indica | Yes | 1849 | |
| ‘Adonis’ | obtusum | Yes | 1952 | |
| ‘Adventglöckchen’ | Belgian indica | Yes | 1929 | |
| ‘Ae14’ | Nijland | Yes | ||
| ‘Ae16’ | Nijland | Yes | ||
| ‘Ae22’ | Nijland | Yes | ||
| ‘Afternoon Delight’ | Holly Springs | 1997 | ||
| ‘Ageeth’ | obtusum | 1973 | ||
| ‘Agemaki’ | 総角 | Kurume | Yes | |
| ‘Ai-no-Hikari’ | 愛の光 | satsuki | ||
| ‘Ai-no-Kagayaki’ | 愛の輝 | satsuki | 1980 | |
| ‘Ai-no-Nishiki’ | 愛の錦 | satsuki | Yes | 2007 |
| ‘Ai-no-Tsuki’ | 愛の月 | satsuki | Yes | 1969 |
| ‘Aika’ | 愛花 | satsuki | Yes | 2009 |
| ‘Aiko’ | 愛子 | satsuki | 2002 | |
| ‘Aikoku’ | 愛国 | satsuki | Yes | |
| ‘Aioi’ | 相生 | Kurume | Yes | |
| ‘Aisai’ | 愛妻 | satsuki | 2024 | |
| ‘Aishifu’ | satsuki | Yes | ||
| ‘Aizen-no-Tsuki’ | 愛染の月 | satsuki | 1988 | |
| ‘Akakozan’ | 赤晃山 | satsuki | ||
| ‘Akane’ | 茜 | satsuki | ||
| ‘Akari’ | あかり | satsuki | 2011 | |
| ‘Akatsuki-no-Zao’ | 暁の蔵王 | satsuki | Yes | |
| ‘Akebono’ | アケボノ | Hirado | Yes | |
| ‘Akemi-no-Tsuki’ | 明美の月 | satsuki | Yes | 1998 |
| ‘Akihime’ | 亜輝姫 | satsuki | Yes | 2012 |
| ‘Akoyahime’ | 阿古耶姫 | satsuki | Yes | |
| ‘Al Reid’ | Stewart | Yes | ||
| ‘Aladdin’ | Glenn Dale | 1947 | ||
| ‘Aladdin’ | obtusum | Yes | 1943 | |
| ‘Albert-Elisabeth’ | Belgian indica | Yes | 1921 | |
| ‘Aleida’ | obtusum | |||
| ‘Alexander’ | North Tisbury | Yes | 1962 | |
| ‘Alexandre II’ | Belgian indica | Yes | 1857 | |
| ‘Alice’ | Belgian indica | Yes | 1870 | |
| ‘Alice’ | obtusum | Yes | 1922 | |
| ‘Alight’ | Glenn Dale | |||
| ‘Allison Ann’ | Stewart | Yes | ||
| ‘Amagasa’ | 天笠 | satsuki | Yes | 1960 |
| ‘Amagi’ | 天城 | satsuki | 2007 | |
| ‘Ambrosianum’ | Belgian indica | Yes | 1948 | |
| ‘Ambrosii’ | Belgian indica | 1840 | ||
| ‘Amelia Mary’ | Klimavicz | Yes | 2023 | |
| ‘Amherst’ | Stewart | Yes | ||
| ‘Amoenum’ | obtusum | Yes | 1851 | |
| ‘Andrea Jeanne’ | Klimavicz | Yes | 2023 | |
| ‘Andros’ | Glenn Dale | 1941 | ||
| ‘Ann Lee McPhail’ | Harris | Yes | 2008 | |
| ‘Anna Kehr’ | Yes | 1961 | ||
| ‘Anne Frank’ | obtusum | Yes | 1965 | |
| ‘Annina’ | Belgian indica | Yes | 1984 | |
| ‘Antoinette Martin’ | Klimavicz | Yes | 2013 | |
| ‘Anytime’ | Belgian indica | |||
| ‘Anytime Tetra’ | ||||
| ‘Ao-no-Hana’ | 碧の華 | satsuki | 2024 | |
| ‘Aoi’ | 葵 | satsuki | 1970 | |
| ‘Aoi-no-Yume’ | 蒼衣の夢 | satsuki | 2013 | |
| ‘Aozora’ | 碧空 | satsuki | Yes | 1975 |
| ‘Aphrodite’ | Glenn Dale | 1941 | ||
| ‘Apollo’ | Belgian indica | Yes | 1878 | |
| ‘April Elaine Sanborn’ | Stewart | Yes | ||
| ‘Aquarell’ | Belgian indica | Yes | 1990 | |
| ‘Arabesk’ | Vuyk | Yes | 1970 | |
| ‘Arctic Fox’ | Glendoick | 1998 | ||
| ‘Ardeur’ | obtusum | |||
| ‘Arlequin’ | Belgian indica | Yes | 1885 | |
| ‘Armand Haerens’ | Belgian indica | 1923 | ||
| ‘As4’ | Nijland | Yes | ||
| ‘Asagasumi’ | 朝霞 | Kurume | Yes | |
| ‘Asagiri’ | あさぎり | satsuki | 2007 | |
| ‘Asahi-no-Hikari’ | 旭の香 | satsuki | ||
| ‘Asahi-no-Izumi’ | 旭の泉 | satsuki | Yes | 1975 |
| ‘Asahi-sakigake’ | 旭魁 | Belgian indica | Yes | 1978 |
| ‘Asahizuru’ | 旭鶴 | satsuki | Yes | |
| ‘Asahizuru’ | 旭鶴 | Kurume | Yes | |
| ‘Asazakura’ | 朝桜 | satsuki | Yes | 1984 |
| ‘Ashley Ruth’ | Stewart | Yes | ||
| ‘Astronaut’ | Holly Springs | Yes | ||
| ‘Asuka’ | 明日香 | satsuki | Yes | 1991 |
| ‘Asuka-no-Hikari’ | 飛鳥の光 | satsuki | ||
| ‘Asuka-no-Homare’ | 飛鳥の誉 | satsuki | Yes | 2002 |
| ‘Asukabijin’ | あすかびじん | satsuki | 2014 | |
| ‘Asukanishiki’ | 飛鳥錦 | satsuki | Yes | 2002 |
| ‘Asukayama’ | 明日香山 | satsuki | Yes | 2002 |
| ‘Atsumizakura’ | 昌三桜 | Kurume | Yes | |
| ‘Audrey Stelloh’ | Stewart | Yes | ||
| ‘Aurelia’ | Belgian indica | Yes | 1857 | |
| ‘Auseklītis’ | Latvian | Yes | ||
| ‘Autumn Chiffon’ | Encore | Yes | 1998 | |
| ‘Autumn Coral’ | Encore | Yes | 1998 | |
| ‘Autumn Debutante’ | Encore | Yes |