|Paeonia lactiflora 'Kelway's Glorious'|
Fragrant, double white flowers with creamy-yellow centre.
|Papaver orientale ''Medallion''|
Long-blooming variety. Plum-red flowers fading to dusky pink.
|Penstemon 'Pensham Plum Jerkum'|
Plum-purple flowers with white mottled throats.
Also known as White Bedder. Clusters of large white, tubular flowers over a long season.
|Perovskia 'Blue Spire'|
Aromatic, silver-grey foliage. Bright blue flowers.
|Persicaria amplexicaulis 'Pink Lady'|
Pink flower spikes. Large pointed leaves.
|Persicaria bistorta 'Superba'|
Large, fat pink spikes in early to mid summer. To 30in (75cm). Sun or part shade. Needs moist soil. Good in borders or along edge of pond. Insect friendly.
|Persicaria campanulata 'Alba'|
Slender, branched spikes of small, pale pink flowers on tall stems over deeply-veined leaves.
Attractive chevron-marked leaves. Spikes of small red flowers.
|Persicaria virginiana var filiformis 'Painter's Palette'|
Green and cream marbled leaves with red chevron in centre.
Whorls of tubular, pale yellow flowers. Rough-textured, sage-like leaves.
|Phlox carolina 'Miss Lingard'|
Upright perennial with clusters of large, pure white flowers.
|Phlox maculata 'Omega'|
Fragrant white flowers with lilac eye.
|Phlox paniculata 'Norah Leigh'|
Creamy variegated leaves. Many pale mauve flowers with pink eyes.
|Phlox paniculata 'Tiara'|
Dense heads of creamy-white, scented flowers with green tinge.
|Phlox paniculata 'Eden's Flash'|
Bright pink flowers with darker eye.
|Phlox paniculata 'David'|
Bright green leaves and fragrant, clear white flowers.
|Phlox paniculata 'Starfire'|
Upright form Large panicles of crimson flowers over red-tinged leaves.
|Phlox paniculata 'Uspekh'|
Fragrant lilac flowers with large, white star centres.
|Phlox paniculata 'Othello'|
Claret red, lightly scented flowers over purple-flushed, dark green leaves.
|Phlox paniculata 'Prince of Orange'|
Scented, orange-red flowers in large panicles.
|Phlox paniculata 'Tenor'|
Deep red-pink, scented flowers over dark foliage.
|Phlox paniculata 'Blue Paradise'|
Rounded heads of fragrant, dark-eyed, violet-blue flowers.
|Physostegia virginiana 'Miss Manners'|
Spikes of white, tubular flowers.
|Physostegia virginiana 'Vivid'|
Dense spikes of dark rose flowers.
Dramatic, fast-growing, herbaceous perennial. White or pink flower spikes develop into dark maroon berries.
|Plectranthus argentatus 'Hill House'|
Silver-green leaves edged with cream. Spikes of lilac flowers.
|Plectranthus argentatus 'Silver Shield'|
Foliage plant. Bold silver grey, furry leaves. Pale blue-white flowers.
|Polemonium 'Lambrook Mauve'|
Compact hybrid, more delicate than other polemoniums. Soft pink-mauve flowers over ferny foliage.
|Polemonium 'Northern Lights'|
Soft blue flowers, slightly scented, over ferny foliage.
|Polemonium 'Sonia's Bluebell'|
Pale blue, bell-shaped flowers with ferny foliage over a long period.
|Polemonium 'Pink Beauty'|
Divided green leaves with mauve-pink, bell-shaped flowers.
|Polygala x dalmaisiana|
Bushy evergreen shrub with pea-like, reddish-purple flowers.
|Polypodium 'Whitley Giant'|
Fern with very attractive, broad, evergreen fronds.
|Polystichum setiferum 'Pucherrimum Bevis'|
Elegant fern with divided, deep green, lace-like fronds.
|Potentilla 'Monsieur Rouillard'|
Clusters of double or semi-double, rich red flowers.
|Primula 'Dark Rosaleen'|
Deep red flowers with yellow eye over glossy, bronze leaves.
|Primula 'Elizabeth Killelay'|
Double lace-cap primula. Maroon with gold edge.
Unusual green-yellow flowers with yellow eye.
|Primula 'Kusham Krishna'|
Grey-green crinkled foliage. Large, deep violet flowers with white eye.
|Primula 'Tie Dye'|
Scented, long-lasting blue flowers with white markings and yellow eyes.
Flat rosette of crinkly leaves. Whorls of reddish-pink flowers.
Red buds open into whorls of orange-yellow flowers around upright stems.
Upright, mealy-white stems bearing large reddish-purple flowers.
|Primula sieboldii 'Snowdrop'|
Pure white flowers from rosette of leaves.
|Primula veris 'Katy McSparron'|
Scented, deep yellow flowers like cowslips but fully double.
|Prunella vulgaris 'Rosenkugel'|
Also known as Prunella 'Rose Pearl'. Purple-pink two-lipped flowers. Compact habit.
|Pulmonaria 'Blue Ensign'|
Large, bright blue flowers over dark green leaves.
|Pulmonaria 'Diana Clare'|
Attractive silver-marked leaves for several months Purple-blue flowers. 12in (30cm) Prefers some shade.
Semi-evergreen perennial with silver-speckled leaves. Clear, pale blue flowers opening from pale pink buds.
|Pulsatilla vulgaris 'Heiler hybrids'|
Hairy buds open into flowers of red, pink, violet, cream or white. Attractive fluffy seedheads useful in flower arranging.
|Pulsatilla vulgaris 'Papageno'|
Large, semi-double with fringed petals, in purple, pink, red or white.
Attractive silky seed heads.
|Pulsatilla vulgaris 'Alba'|
Pure white, bell-shaped flowers followed by attractive seed heads.
|Puschkinia scilloides var libanotica|
Small, star-shaped, near white flowers with pale blue stripe.