This is a partial list of garden plants, plants that can be cultivated in gardens in North America, listed alphabetically by genus.
- Cabomba
- Cadia
- Caesalpinia (dwarf poinciana, Pride of Barbados)
- Caladium
- Calamagrostis (reed grass, smallweed)
- Calamintha (calamint)
- Calamus
- Calandrinia
- Calanthe an orchid genus
- Calathea
- Calceolaria (slipperwort)
- Calendula (pot marigold)
- Calibanus
- Calibrachoa
- Calla
- Calliandra
- Callianthemum
- Callicarpa (beauty berry)
- Callicoma (black wattle)
- Callirhoe (poppy mallow)
- Callisia
- Callistemon (bottlebrush)
- Callistephus (Chinese aster)
- Callitriche (water starwort)
- Callitris (cypress pine)
- Calluna (heather)
- Calocedrus (incense cedar)
- Calochone
- Calochortus
- Calodendrum (cape chestnut)
- Calomeria
- Calophaca
- Calophyllum
- Calopyxis
- Caloscordum
- Calothamnus
- Calotropis
- Calpurnia
- Caltha (kingcup, marsh marigold)
- Calycanthus
- Calymmanthium
- Calypso (an orchid genus)
- Calytrix (starflower)
- Camassia (quamash)
- Camellia
- Camoensia
- Campanula (bellflower)
- Campsis (trumpet vine)
- Campylotropis (See Lespedeza)
- Cananga (ylang ylang)
- Canarina
- Canistrum
- Canna
- Cantua
- Capparis
- Capsicum (pepper)
- Caragana (peashrub)
- Caralluma
- Cardamine (bittercress)
- Cardiocrinum
- Cardiospermum
- Cardwellia
- Carex (sedge)
- Carissa
- Carlina
- Carludovica
- Carmichaelia
- Carnegiea (saguaro)
- Carpentaria
- Carphalea
- Carpinus (hornbeam)
- Carpobrotus
- Carthamus (safflower)
- Carum (caraway)
- Carya (hickory, pecan)
- Caryopteris
- Caryota (fishtail palm)
- Cassia (shower tree)
- Cassinia
- Cassiope
- Cassipourea
- Castanea (chestnut)
- Castanopsis
- Castanospermum (black bean)
- Casuarina (sheoak)
- Catalpa (Indian bean)
- Catananche
- Catasetum (an orchid genus)
- Catha (khat tree)
- Catharanthus (Madagascar periwinkle)
- Catopsis
- Cattleya (an orchid genus)
- Caulophyllum
- Cautleya
- Cavendishia
- Ceanothus (California-lilac)
- Cedrela (toon)
- Cedronella
- Cedrus (cedar)
- Ceiba (kapok)
- Celastrus (staff-vine)
- Celmisia (New Zealand daisy, New Zealand aster)
- Celosia (cockscomb)
- Celtis (hackberry)
- Centaurea
- Centaurium
- Centradenia
- Centranthus (valerian)
- Cephalaria
- Cephalocereus
- Cephalophyllum
- Cephalotaxus (plum-yew)
- Ceraria
- Cerastium
- Ceratonia (St. John's bread, carob bean)
- Ceratopetalum (coachwood)
- Ceratophyllum
- Ceratopteris
- Ceratostigma
- Ceratozamia
- Cerbera (sea mango)
- Cercidiphyllum
- Cercis (Judas tree, redbud)
- Cercocarpus
- Cereus
- Ceropegia
- Cestrum
- Chadsia
- Chaenomeles (flowering quince)
- Chaenorhinum (dwarf snapdragon)
- Chaerophyllum
- Chamaecyparis (false cypress)
- Chamaecytisus
- Chamaedaphne
- Chamaedorea
- Chamaelirium
- Chamaemelum (chamomile)
- Chamaerops
- Chamelaucium (wax flower)
- Chasmanthe
- Chasmanthium
- Cheilanthes
- Cheiridopsis
- Chelidonium
- Chelone (turtlehead)
- Chiastophyllum
- Chiliotrichum
- Chilopsis (desert willow)
- Chimaphila
- Chimonanthus (wintersweet)
- Chimonobambusa
- Chionanthus (fringe tree)
- Chionochloa
- Chirita
- Chlidanthus
- Choisya
- Chonemorpha (Frangipani vine)
- Choricarpia (brush turpentine)
- Chorisia (floss silk tree)
- Chorizema
- Chrysalidocarpus
- Chrysanthemoides
- Chrysanthemum
- Chrysobalanus
- Chrysogonum
- Chrysolepis
- Chrysophyllum (star apple)
- Chrysothemis
- Chusquea
- Cibotium
- Cicerbita
- Cichorium (chicory, endive)
- Cimicifuga (bugbane)
- Cinnamomum (camphor laurel)
- Cionura
- Cirsium
- Cissus
- Cistus (rock rose, sun rose)
- Citharexylum (fiddlewood)
- Citrofortunella (hybrid)
- Citrus (lime, lemon)
- Cladanthus
- Cladrastis
- Clarkia
- Claytonia
- Cleistocactus
- Clematis
- Cleome (spider flower)
- Clerodendrum
- Clethra (summersweet)
- Cleyera
- Clianthus
- Clintonia
- Clitoria
- Clivia
- Clusia
- Clytostoma
- Cobaea
- Coccoloba (sea grape)
- Coccothrinax (thatch palm)
- Cocculus
- Cochlioda an orchid genus – synonym of Oncidium
- Cochlospermum (buttercup tree, Maximiliana)
- Cocos (coconut)
- Codiaeum (croton)
- Codonanthe
- Codonopsis
- Coelia
- Coelogyne (an orchid genus)
- Coffea (coffee tree)
- Coix
- Colchicum (autumn crocus, meadow saffron)
- Coleonema
- Colletia
- Collinsia
- Collomia
- Colocasia (taro)
- Colquhounia
- Columnea
- Colutea (bladder senna)
- Coluteocarpus
- Colvillea
- Combretum
- Comesperma
- Commelina (day flower, spiderwort, widow's tears)
- Commersonia
- Commidendrum
- Commiphora
- Comptonella
- Comptonia (Sweetfern)
- Conandron
- Congea
- Conicosia
- Coniogramme
- Conoclinium (mistflower)
- Conophytum
- Conospermum
- Conostylis
- Conradina
- Consolida (larkspur)
- Convallaria (lily-of-the-valley)
- Convolvulus (bindweed, morning glory)
- Copernicia (caranda palm, wax palm)
- Copiapoa syn. Pilocopiapoa
- Coprosma
- Coptis (goldthread)
- Cordia (bird lime tree)
- Cordyline
- Coreopsis (tickseed)
- Coriandrum (coriander cilantro)
- Coriaria
- Cornus (dogwood, cornel)
- Corokia
- Coronilla
- Correa
- Corryocactus
- Cortaderia (pampas grass, tussock grass)
- Cortusa
- Corybas (helmet orchid)
- Corydalis
- Corylopsis (winter-hazel)
- Corylus (hazel, filbert)
- Corymbia
- Corynocarpus
- Corypha
- Coryphantha
- Cosmos
- Costus
- Cotinus (smoke bush)
- Cotoneaster
- Cotula (brass buttons)
- Cotyledon
- Couroupita (cannonball tree)
- Crambe
- Craspedia
- Crassula
- + Crataegomespilus (graft chimera)
- Crataegus (hawthorn)
- × Crataemespilus (hybrid)
- Crepis
- Crescentia (calabash)
- Crinodendron
- Crinum
- Crocosmia (falling stars, montbretia)
- Crocus
- Crossandra (firecracker flower)
- Crotalaria (rattlepod)
- Croton
- Crowea
- Cryptanthus (earth stars)
- Cryptbergia (hybrid)
- Cryptocarya
- Cryptocoryne (water trumpet)
- Cryptomeria (sugi, Japanese cedar)
- Cryptostegia (Indian rubber vine)
- Cryptotaenia
- Ctenanthe
- Cucumis
- Cucurbita
- Cuminum
- Cunila
- Cunninghamia (China-fir)
- Cunonia
- Cupaniopsis (tuckeroo)
- Cuphea
- Cupressus (cypress)
- Cuprocyparis (hybrid)
- Curcuma
- Cussonia
- Cyananthus (trailing bellflower)
- Cyanotis
- Cyathea (tree fern)
- Cyathodes
- Cybistax
- Cycas (cycad, sago palm)
- Cyclamen
- Cycnoches an orchid genus
- Cydista, synonym of Bignonia
- Cydonia (quince)
- Cylindropuntia
- Cymbalaria (ivy-leaved toadflax)
- Cymbidium (an orchid genus)
- Cymbopogon
- Cynara
- Cynodon
- Cynoglossum (hound's tongue)
- Cypella
- Cyperus
- Cyphomandra (tree tomato)
- Cyphostemma
- Cypripedium (lady's slipper; an orchid genus)
- Cyrilla
- Cyrtanthus (fire lily)
- Cyrtomium
- Cyrtostachys
- Cystopteris (bladder fern)
- Cytisus (broom)
- Pachistima
- Pachycereus
- Pachycormus
- Pachycymbium
- Pachyphragma
- Pachyphytum
- Pachypodium
- Pachysandra
- Pachystachys
- Pachystegia
- Pachystima
- Pachyveria (hybrid genus)
- Paeonia (peony)
- Paliurus
- Pamianthe
- Panax (ginseng)
- Pancratium (sea lily)
- Pandanus (screw pine)
- Pandorea
- Panicum
- Pansy
- Papaver (poppy)
- Paphiopedilum (slipper orchid)
- Paradisea (paradise lily)
- Parahebe
- Paraquilegia
- Parkinsonia
- Parnassia
- Parochetus
- Parodia
- Paronychia
- Parrotia
- Parrotiopsis
- Parthenocissus
- Passiflora (granadilla, passionflower)
- Patersonia
- Patrinia
- Paulownia
- Paurotis
- Pavonia
- Pedilanthus
- Pediocactus
- Pelargonium (geranium)
- Pellaea
- Peltandra (arrow arum)
- Peltoboykinia
- Peltophorum
- Peniocereus
- Pennisetum
- Penstemon
- Pentachondra
- Pentaglottis
- Pentas
- Peperomia
- Peraphyllum
- Pereskia
- Perezia
- Pericallis
- Perilla
- Periploca
- Perovskia (now included in Salvia)
- Pernettya (now included in Gaultheria)
- Persea
- Persicaria (fleeceflower, knotweed)
- Petasites (butterbur, sweet coltsfoot)
- Petrea
- Petrocosmea
- Petrophile
- Petrophytum
- Petrorhagia
- Petroselinum (parsley)
- Petteria
- Petunia
- Phacelia
- Phaedranassa (queen lily)
- Phaius (an orchid genus)
- Phalaenopsis (moth orchid)
- Phalaris
- Phebalium
- Phegopteris (beech fern)
- Phellodendron (cork tree)
- Philadelphus (mock orange)
- Philageria (hybrid genus)
- Philesia
- Phillyrea
- Philodendron
- Phlebodium
- Phlomis
- Phlox
- Phoenix (date palm)
- Phormium
- Photinia
- Phragmipedium (an orchid genus)
- Phragmites (reed)
- Phuopsis
- Phygelius
- Phylica (Cape myrtle)
- × Phylliopsis (hybrid genus)
- Phyllocladus (toatoa)
- Phyllodoce
- Phyllostachys
- Phyllothamnus (hybrid genus)
- Physalis (ground cherry)
- Physaria (bladderpod)
- Physocarpus
- Physoplexis
- Physostegia
- Phyteuma
- Phytolacca (pokeweed)
- Picea (spruce)
- Picrasma
- Pieris
- Pilea
- Pileostegia
- Pilosella
- Pilosocereus
- Pimelea
- Pimpinella
- Pinanga
- Pinckneya
- Pinellia
- Pinguicula (butterwort)
- Pinus (pine)
- Piper (pepper)
- Piptanthus
- Pisonia
- Pistacia (pistachio)
- Pistia
- Pitcairnia
- Pithecellobium
- Pittosporum
- Pityrogramma
- Plantago (plantain)
- Platanus (plane tree, sycamore)
- Platycarya
- Platycerium (staghorn fern)
- Platycladus (Chinese arborvitae)
- Platycodon (balloon flower)
- Platystemon (creamcups)
- Plectranthus an orchid genus
- Pleioblastus
- Pleione (an orchid genus)
- Pleiospilos (living granite)
- Pleurothallis (an orchid genus)
- Plumeria (frangipani)
- Poa
- Podalyria
- Podocarpus
- Podophyllum (mayapple)
- Podranea
- Polemonium (jacob's ladder, abscess root)
- Polianthes
- Poliothyrsis
- Polygala (milkwort, seneca, snakeroot)
- Polygonatum
- Polygonum (knotweed, knotgrass)
- Polypodium
- Polyscias
- Polystichum
- Poncirus
- Pongamia
- Pontederia (pickerel weed)
- Populus (aspen, poplar, cottonwood)
- Porana
- Portea
- Portulaca (purslane, moss rose)
- Portulacaria
- Posoqueria
- Potamogeton
- Potentilla (cinquefoil)
- Pothos
- × Potinara (hybrid orchid genus)
- Pratia
- Primula (primrose)
- Prinsepia
- Pritchardia
- Proboscidea (unicorn plant)
- Promenaea an orchid genus
- Prosopis (mesquite)
- Prostanthera (mint bush)
- Protea
- Prumnopitys
- Prunella (self-heal)
- Prunus (almond, apricot, cherry, peach, plum)
- Pseuderanthemum
- Pseudocydonia
- Pseudolarix (golden-larch)
- Pseudopanax
- Pseudosasa
- Pseudotsuga (douglas-fir)
- Pseudowintera
- Psilotum
- Psychopsis (butterfly orchid)
- Psylliostachys (statice)
- Ptelea
- Pteris (brake, table fern)
- Pterocactus
- Pterocarya (wingnut)
- Pteroceltis
- Pterocephalus
- Pterodiscus
- Pterostyrax
- Ptilotus
- Ptychosperma
- Pueraria
- Pulmonaria (lungwort)
- Pulsatilla
- Pultenaea
- Punica (pomegranate)
- Purshia
- Puschkinia
- Putoria
- Puya
- Pycnanthemum
- Pycnostachys
- Pyracantha (firethorn)
- Pyrola (wintergreen)
- Pyrostegia
- Pyrrosia
- Pyrus (pear)