- Oak Leaf Lettuce
- Oats, Hulless
- Obus or Kroumir Melon
- Odessa Market Pepper
- Ojo De Cabra
- Oka Melon ( Bizard Island Strain )
- Old Greek Melon
- Old Homestead (Kentucky Wonder)
- Old Homestead Bedding Petunia
- Old Italian Tomato
- Old Spice Mix Sweet Pea
- Old Time Tennessee Melon
- Old Timer or Purple Hull Speckled Cowpea
- Old Yellow Candy Stripe
- Omaha Pumpkin
- Omar's Lebanese Tomato
- Onavas Red
- Opopeo - Amaranth
- Oran's Melon
- Orange & Green Zebra Tomato
- Orange Banana Tomato
- Orange Bell
- Orange Cushaw
- Orange Flesh Tendersweet
- Orange Fleshed Purple Smudge
- Orange Giant Amaranth
- Orange Gleam Nasturtium
- Orange Gourd
- Orange Hawaii - Marigold, French
- Orange Icicle Tomato
- Orange King - Zinnia
- Orange King Calendula
- Orange Master Pomegranate
- Orange Porcupine - Calendula
- Orange Strawberry
- Orange Sun Pansy
- Orangeglo
- Oregano Vulgare
- Oregano, Wild Zaatar
- Oregon Sugar Pod II Snow Pea
- Oriental Scarlet - Poppy
- Oriole - Zinnia
- Oriole Orange Chard
- Orlinabel Melon
- Ornamental Fringed Mix
- Osh Kirgizia
- Outredgeous
- Ozark Giant Pepper



































