- HuodendronHuodendron biaristatum
- Huzarenknoop 'Santiago Yellow'Sanvitalia procumbens 'Santiago Yellow'
- IepenzwamHypsizygus ulmarius
- IJsbloem 'New Fire'Deosperma 'New Fire'
- IJsbloem 'White Nugget'Delosperma basuticum 'White Nugget'
- IJzerkruid 'Summer Surrender'Vernonia 'Summer Surrender'
- Iliamna remotaIliamna remota
- Illicium merrillianumIllicium merrillianum
- ImmortelleXeranthemum cylindraceum
- Incalelie 'Havana'Alstroemeria Inticancha-Sun 'Havana'
- Incalelie 'Inca Goal'Alstroemeria 'Inca Goal'
- Incalelie 'Indigo'Alstroemeria inticancha 'Indigo'
- Incalelie 'Nicolas'Alstroemeria 'Nicolas'
- Incalelie 'Princess Sara'Alstroemeria 'Princess Sara'
- Incalelie 'Summer Break'Alstroemeria 'Summer Break'
- Incallelie 'Leonie'Alstroemeria 'Leonie'
- Indiase Meidoorn 'Coates' Crimson'Rhaphiolepis delacourii 'Coates' Crimson'
- Iris 'Agripinella'Iris ensata 'Agripinella'
- Iris 'Andy Dandy'Iris louisiana 'Andy Dandy'
- Iris 'Art World'Iris louisiana 'Art World'
- Iris 'Belgium Crown'Iris ensata 'Belgium Crown'
- Iris 'Belgium Warrior'Iris ensata 'Belgium Warrior'
- Iris 'Bellisinado'Iris spuria 'Bellisinado'
- Iris 'Betty Cooper'Iris spuria 'Betty Cooper'
- Iris 'Blaue Milchstrasse'iris sibirica 'Blaue Milchstrasse'
- Iris 'Claret Cup'Iris sibirica 'Claret Cup'
- Iris 'Crystal Halo'Iris ensata 'Crystal Halo'
- Iris 'Declasse'Iris louisiana 'Declasse'
- Iris 'Dreaming Orange'Iris sibirica 'Dreaming Orange'
- Iris 'Final Frontier'Iris louisiana 'Final Frontier'
- Iris 'Galactic Warrior'Iris 'Galactic Warrior'
- Iris 'Gull's Wing'Iris sibirica 'Gull's Wing'
- Iris 'Her Highness'Iris louisiana 'Her Highness'
- Iris 'Hohe Warte'Iris sibirica 'Hohe Warte'
- Iris 'Hubbard'Iris sibirica 'Hubbard'