Spruce

Picea species

Trees and Shrubs, Bonsai

Stratify seed in fridge 3 weeks, and sow on soil surface 2" apart, in spring, needs light to germinate. Tourniquet air layering, started early spring, is slow. Side-veneer grafting also used to propagate specific cultivars, or grow from cuttings of young growth, taken fall or early spring. Likes moist acidic soil and sun to light shade. Suitable for bonsai. Best suited to cooler climates. Zones 1-8

Picea glauca, white spruce, quite tolerant dry conditions, and Picea abies, Norway spruce, of heavier winds; both grow in zones 2-6. Picea pungens glauca, the Colorado blue spruce, will not grow true from seed, but should be grafted to maintain its colour; hardy to zone 2. Picea mariana, the black spruce, hardy into zone 1