In praise of primroses

Basic primula groups
Acaulis - early spring blooms in a rosette of leaves; short plant
Auricula - large clusters of brightly coloured blooms (many with a light centre and darker band around edge); thick, glossy, succulent-like foliage
Candelabra - tiered rings of flowers on tall stem; often self-sows
Juliana - early spring blooms on small, sturdy, evergreen plant
Polyanthus - large flower clusters atop long, thick stems

What primroses crave

• Light, fluffy, well-aerated organic soil with lots of grit—very fine gravel—or sand for alpines or pot-grown plants (see "Soil Mixes," page 3)
• pH between 5 and 7
• Constant supply of moisture and oxygen at the roots (heavy clay soil will need to be lightened with organic matter, grit or both)
• Good drainage—primroses hate wet feet 
• Cool location with protection from hottest mid-afternoon summer sun 
• A moist environment—water well when plant starts to wilt 
• Regular division (every three years). Short-lived varieties such as Primula bulleyana, P. capitata, P. scotica and P. vialii can be propagated from seed
• Regular feeding during the growing season—side-dress with compost or composted manure in spring or fall. Fertilize monthly from spring through early summer with a well-balanced granular or liquid fertilizer such as 4-2-3 or 10-10-10 at half-strength 
• Regular deadheading and removal of dead leaves

Bernard Jackson's favourites

• Primula allionii 'Crowsley Variety' deep pink; spring; full sun to part shade; 10 cm tall and wide; rock garden; Zone 4
• P. capitata (see chart, page 4)
• P. farinosa (see chart) 
• P. japonica 'Postford White' white with yellow eye; late spring to early summer; full sun to part shade; 60 cm x 45 cm; woodland garden; Zone 3
• P. laurentiana (see chart)
• P. marginata 'Linda Pope' blue-purple; early spring; full sun to part shade; 15 cm x 30 cm; rock garden; Zone 4
• P. x polyantha (gold-laced group) yellow centre with dark red petals outlined in gold; spring; full sun to part shade; 30 cm tall and wide; woodland, rock or perennial garden; Zone 4
• P. x pruhoniciana 'Kinlough Beauty' deep rose-pink with darker pink veins and yellow star eye; early spring; full sun to part shade; 20 cm x 30 cm; rock garden; Zone 5
• P. sieboldii 'Mikado' dark magenta-purple with white eye; early spring; full sun to part shade; 25 cm x 30 cm; perennial or woodland garden; Zone 4
• P. vialii (see chart) 
• P. vulgaris 'Alan Robb' pale apricot, double; early spring; full sun to part shade; 20 cm x 25 cm; rock or woodland garden; Zone 3
• P. v. 'Paris 90' white or cream with blue picotee edge or blue and mauve with white background; early spring; full sun to part shade; 15 cm tall and wide; rock or woodland garden; Zone 4
• P. v. 'Quakers Bonnet' mauve-pink, double; early spring; full sun to part shade; 15 cm tall and wide; rock or woodland garden; Zone 4