Plants: N
- Naked Buckwheat Eriogonum nudum Wildflower
- Naked Lady Amaryllis belladonna Bulb
- Nannyberry Viburnum lentago Flowering shrub
- Napa Cabbage Brassica rapa subsp. pekinensis Brassica
- Naples Garlic Allium neapolitanum Allium
- Narrow-Leaved Coneflower Echinacea angustifolia Wildflower
- Narrow-Spiked Ligularia Ligularia stenocephala Garden perennial
- Narrowleaf Blazing Star Liatris punctata var. mucronata
- Narrowleaf Ironweed Vernonia lettermannii Wildflower
- Narrowleaf Mountain Mint Pycnanthemum tenuifolium Wildflower
- Narrowleaf Silkgrass Pityopsis graminifolia
- Narrowleaf Willow Salix exigua Flowering shrub
- Narrowleaf Zinnia Zinnia angustifolia Garden annual
- Nasturtium Tropaeolum majus Leafy
- Nectarine Prunus persica var. nectarina Tree fruit
- Needle Stonecrop Sedum lineare Creeping perennial
- Nemesia Nemesia strumosa Garden annual
- Nepal Cinquefoil Potentilla nepalensis Garden perennial
- Netleaf Hackberry Celtis laevigata var. reticulata
- Nettle-Leaved Mullein Verbascum chaixii Wildflower
- Nettleleaf Giant Hyssop Agastache urticifolia Wildflower
- Nevius' Stonecrop Sedum nevii Creeping perennial
- New England Aster Symphyotrichum novae-angliae Wildflower
- New Guinea Impatiens Impatiens hawkeri Garden annual
- New Jersey Tea Ceanothus americanus Flowering shrub
- New York Aster Symphyotrichum novi-belgii Garden perennial
- New York Fern Thelypteris noveboracensis Fern
- New York Ironweed Vernonia noveboracensis Wildflower
- New Zealand Bur Acaena microphylla Creeping perennial
- New Zealand Spinach Tetragonia tetragonioides Leafy
- New Zealand Tea Tree Leptospermum scoparium Flowering shrub
- Night-Blooming Jasmine Cestrum nocturnum Flowering shrub
- Night-Scented Stock Matthiola longipetala Garden annual
- Nineanther Prairie Clover Dalea enneandra
- Nineleaf Biscuitroot Lomatium triternatum Wildflower
- Nippon Daisy Nipponanthemum nipponicum Flowering shrub
- Nippon Spirea Spiraea nipponica Flowering shrub
- Nodding Ladies' Tresses Spiranthes cernua Wildflower
- Nodding Onion Allium cernuum Wildflower
- Nootka Lupine Lupinus nootkatensis Legume
- Nootka Rose Rosa nutkana Flowering shrub
- Northern Bush Honeysuckle Diervilla lonicera Flowering shrub
- Northern Catalpa Catalpa speciosa Flowering tree
- Northern Red Oak Quercus rubra Nut
- Northern Spicebush Lindera benzoin Herb
- Nutmeg Myristica fragrans Nut