General
Spireas are easy, reliable deciduous shrubs grown for their clouds of flowers and tidy, arching to mounded shapes. Depending on species and cultivar, they bloom either in spring (often white flowers on arching stems) or in summer (commonly pink to reddish blooms on fresh growth). Many varieties also offer attractive foliage—some with golden leaves—and good fall color. Because they are forgiving and hardy, spireas are widely used for low hedges, mixed borders, foundation plantings, and large drifts in parks and public landscapes.
Light
Full sun to partial sun; tolerates light shade but flowers best with more sun.
Soil type
Adaptable; best in well-drained loam with some organic matter, but many types cope with clay if not waterlogged.
Water requirement
Medium; drought tolerant once established, but regular watering improves flowering in dry spells.
Nutrient requirement
Low; a yearly compost mulch is usually enough.
Precultivation
Spireas are usually planted as nursery-grown shrubs. Seed propagation is uncommon in gardens because seedlings vary, and many ornamental cultivars do not come true from seed. If grown from seed, sow on the surface of moist seed mix, keep evenly moist, and provide light for germination. For identical plants, softwood cuttings in early summer or hardwood cuttings in late autumn/winter are more reliable.
Planting
Plant in spring or early autumn when temperatures are cool and soil moisture is dependable. Choose a site with sun to partial sun and enough room for the mature size. Loosen the soil widely, not just deeply, and water thoroughly after planting. A mulch layer helps reduce weeds and keeps soil moisture more even—especially important in the first growing season.
Pruning
Pruning depends on flowering time. Spring-flowering spireas bloom on last year’s shoots, so prune immediately after bloom: remove a portion of the oldest stems at ground level and lightly shorten overly long shoots if needed. Summer-flowering spireas bloom mainly on new growth, so they can be cut back in early spring to stimulate vigorous shoots and abundant flowers. Avoid heavy pruning at the wrong time, as it removes flower buds and reduces display.
Maintenance
Spirea is low maintenance once established. Mulch annually with compost or leaf mold. Water during extended droughts, especially for newly planted shrubs and in very sandy soils. Fertilize lightly in spring if growth is weak—too much nitrogen leads to lush leaves and fewer flowers. Keep the shrub open by thinning older wood periodically to improve airflow and reduce pest and disease pressure.
Harvest
Not applicable, as spirea is grown as an ornamental shrub.
Common issues
Aphids can cluster on fresh shoots, especially in spring; strong water sprays and encouraging beneficial insects often help. Powdery mildew can occur in crowded, humid conditions—thin the shrub and avoid excess nitrogen. Poor flowering is usually due to incorrect pruning timing or too much shade.
Pollination
Insect-pollinated; attracts bees and other beneficial insects.
Companion plants
Lilac, mock orange, forsythia, hydrangea, ornamental grasses, spring bulbs.
Incompatible plants
Plants requiring permanently wet soil or deep shade.
