Plants: P
- Pa'u O Hi'iaka Jacquemontia ovalifolia ssp. sandwicensis Creeping perennial
- Pacific Aster Symphyotrichum chilense Wildflower
- Pacific Bleeding Heart Dicentra formosa Wildflower
- Pacific Crabapple Malus fusca Flowering tree
- Pacific Dogwood Cornus nuttallii Flowering tree
- Pacific Madrone Arbutus menziesii Flowering tree
- Pacific Ninebark Physocarpus capitatus Flowering shrub
- Pacific Rhododendron Rhododendron macrophyllum Flowering shrub
- Pacific Silverweed Argentina egedii Creeping perennial
- Pacific Trillium Trillium ovatum Wildflower
- Pagoda Dogwood Cornus alternifolia Flowering tree
- Pagoda Flower Clerodendrum paniculatum
- Painted Daisy Tanacetum coccineum Garden perennial
- Painted Sage Salvia viridis Garden annual
- Painted Tongue Salpiglossis sinuata Garden annual
- Pale Beardtongue Penstemon pallidus Wildflower
- Pale Evening Primrose Oenothera pallida Wildflower
- Pale Purple Coneflower Echinacea pallida Wildflower
- Pale Yellow-Eyed Grass Sisyrinchium striatum Wildflower
- Paleleaf Sunflower Helianthus strumosus Wildflower
- Palm Sedge Carex muskingumensis Grass sedge
- Palmer's Penstemon Penstemon palmeri Wildflower
- Panicle Hydrangea Hydrangea paniculata Flowering shrub
- Panicledleaf Ticktrefoil Desmodium paniculatum
- Pansy Viola × wittrockiana Garden annual
- Paper Birch Betula papyrifera
- Paper Daisy Rhodanthe chlorocephala Garden annual
- Paperflower Psilostrophe tagetina Wildflower
- Paperwhite Narcissus papyraceus Bulb
- Paprika Capsicum annuum Fruiting
- Parrot Lily Alstroemeria psittacina Garden perennial
- Parrot's Beak Lotus berthelotii Flowering shrub
- Parrot's Beak Heliconia Heliconia psittacorum Garden perennial
- Parry's Penstemon Penstemon parryi Wildflower
- Parsley Petroselinum crispum Herb
- Parsley Hawthorn Crataegus marshallii Flowering tree
- Parsnip Pastinaca sativa Root
- Parsnipflower Buckwheat Eriogonum heracleoides Wildflower
- Partridge Pea Chamaecrista fasciculata Wildflower
- Partridgeberry Mitchella repens Creeping perennial
- Pasque Flower Pulsatilla vulgaris Wildflower
- Path Rush Juncus tenuis Creeping perennial
- Pawpaw Asimina triloba Tree fruit
- Peach Prunus persica Tree fruit
- Peach-Leaved Bellflower Campanula persicifolia Garden perennial
- Peacock Ginger Kaempferia pulchra Creeping perennial
- Peacock Spikemoss Selaginella uncinata Moss like
- Peanut Arachis hypogaea Legume
- Pear Pyrus communis Tree fruit
- Pearl Millet Pennisetum glaucum Grain
- Pearlbush Exochorda racemosa Flowering shrub
- Pearly Everlasting Anaphalis margaritacea Wildflower
- Peas Pisum sativum Legume
- Pecans Carya illinoinensis Nut
- Pennsylvania Sedge Carex pensylvanica Grass sedge
- Peony Paeonia lactiflora Garden perennial
- Peppermint Mentha × piperita Herb
- Peregrina Jatropha integerrima Flowering shrub
- Perennial Cornflower Centaurea montana Garden perennial
- Perennial Pea Lathyrus latifolius Garden perennial
- Perennial Peanut Arachis glabrata Creeping perennial
- Perennial Ryegrass Lolium perenne Grass
- Perilla Perilla frutescens Herb
- Persian Barrenwort Epimedium pinnatum Creeping perennial
- Persian Buttercup Ranunculus asiaticus Garden perennial
- Persian Catmint Nepeta racemosa Creeping perennial
- Persian Cyclamen Cyclamen persicum Garden perennial
- Persian Lilac Syringa × persica Flowering shrub
- Persian Lily Fritillaria persica Bulb
- Persian Onion Allium aflatunense Bulb
- Persimmon Diospyros kaki Tree fruit
- Peruvian Lily Alstroemeria aurea Garden perennial
- Peruvian Verbena Glandularia peruviana Creeping perennial
- Peruvian Zinnia Zinnia peruviana Garden annual
- Petunia Petunia × atkinsiana Garden annual
- Pfitzer Juniper Juniperus × pfitzeriana Creeping perennial
- Philadelphia Fleabane Erigeron philadelphicus Wildflower
- Pickerelweed Pontederia cordata
- Piedmont Azalea Rhododendron canescens Flowering shrub
- Pigeon Pea Cajanus cajan Legume
- Piggyback Plant Tolmiea menziesii Creeping perennial
- Pin Cherry Prunus pensylvanica Tree fruit
- Pincushion Flower Scabiosa columbaria Garden perennial
- Pincushion Protea Leucospermum cordifolium Flowering shrub
- Pindo Palm Butia odorata Fruiting
- Pineapple Guava Acca sellowiana Fruiting
- Pineapple Lily Eucomis comosa Bulb
- Pineapple Sage Salvia elegans Flowering shrub
- Pineleaf Penstemon Penstemon pinifolius Wildflower
- Pinemat Manzanita Arctostaphylos nevadensis Creeping perennial
- Pineneedle Milkweed Asclepias linaria
- Pinewoods Milkweed Asclepias humistrata
- Pink Calla Zantedeschia rehmannii Garden perennial
- Pink Evening Primrose Oenothera speciosa Creeping perennial
- Pink Honeysuckle Lonicera hispidula Vine
- Pink Jasmine Jasminum polyanthum Vine
- Pink Muhly Muhlenbergia capillaris Grass
- Pink Popcorn Blueberry Vaccinium corymbosum Berry
- Pink Rain Lily Zephyranthes grandiflora
- Pink Tickseed Coreopsis rosea
- Pink Trumpet Tree Tabebuia heterophylla Flowering tree
- Pink Trumpet Vine Podranea ricasoliana Vine
- Pink Turtlehead Chelone lyonii Garden perennial
- Pinkscale Blazing Star Liatris elegans Wildflower
- Pinkshell Azalea Rhododendron vaseyi Flowering shrub
- Pinxterbloom Azalea Rhododendron periclymenoides Flowering shrub
- Pipevine Aristolochia macrophylla Vine
- Pistachio Pistacia vera Nut
- Pitcher's Leather Flower Clematis pitcheri Vine
- Plains Coreopsis Coreopsis tinctoria Garden annual
- Plains Pricklypear Opuntia polyacantha Fruiting
- Plantain Pussytoes Antennaria plantaginifolia Creeping perennial
- Plantainleaf Sedge Carex plantaginea Grass sedge
- Plum Prunus domestica Tree fruit
- Plume Poppy Macleaya cordata Garden perennial
- Plumleaf Azalea Rhododendron prunifolium Flowering shrub
- Poet's Daffodil Narcissus poeticus Garden perennial
- Poinsettia Euphorbia pulcherrima
- Point Reyes Ceanothus Ceanothus gloriosus Low shrub
- Pointleaf Manzanita Arctostaphylos pungens Flowering shrub