Spicebush: expert tips for growing this native shrub

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Northern spicebush is one of those quietly excellent shrubs that earns its place three times over: a haze of tiny sulphur-yellow flowers on bare twigs in early spring, glossy aromatic foliage all summer, then a clean butter-yellow autumn display that lights up shade. Crush a leaf or scratch a twig and you release a warm, citrus-and-allspice scent that gives the plant its common name. It is also one of the most valuable wildlife shrubs for a woodland edge, feeding both butterflies and migrating birds.

Growing conditions

Spicebush is a natural understorey shrub, so it copes with more shade than almost any other spring-flowering deciduous shrub. In deep shade it becomes open and rangy with sparse fruit; in dappled light or half a day of sun it builds a dense, rounded frame. Full sun is tolerated only where the soil stays reliably moist.

The ideal soil is a moisture-retentive woodland loam, rich in leaf mould and free of waterlogging in winter. A pH between 5.0 and 6.8 suits it best, and thin chalky soils frequently cause yellowing between the leaf veins. It will grow happily on clay provided the surface does not bake hard in summer.

Cold is no obstacle — established plants shrug off severe winters — but drought and dry, reflected heat are. In warmer or drier regions, site it on a north or east aspect, or in the shelter of taller deciduous trees.

How to plant Lindera

Plant container-grown shrubs in autumn, from October onwards, so the roots settle while the soil is still warm and naturally moist. Early spring planting also works well, provided you commit to watering through the first summer.

• Spacing: allow 2–2.5 m between specimen shrubs; drop to 1.2–1.5 m if you want an informal thicket or wildlife hedge to knit together.
• Depth: set the root ball so its surface sits flush with the surrounding soil — planting proud exposes the shallow, fibrous roots to drying.
• Soil preparation: fork a generous barrowload of leaf mould or composted bark into the planting area rather than just the hole, encouraging roots to travel outwards.
• Watering in: soak thoroughly, then apply a 7–8 cm mulch kept clear of the stems; repeat watering weekly in dry spells for the first two seasons.
• For fruit: plant at least one male within roughly 15 m of your females — a ratio of one male to five or six females is ample.
• Propagation: take softwood cuttings in early summer with bottom heat, or sow cleaned seed in autumn; seed must never be allowed to dry out and needs about three months of cold, moist stratification at 4 °C.

Care through the seasons

Spring: Enjoy the flowers on bare wood in March and April, then top up the mulch as growth begins. A light feed of leaf mould or a balanced organic fertiliser is plenty; heavy nitrogen produces soft, floppy shoots. There is no need to deadhead.

Summer: Water deeply during dry spells — spicebush is shallow-rooted and shows drought stress quickly as scorched leaf margins and early leaf fall. Expect spicebush swallowtail caterpillars to fold leaves into neat shelters; leave them be, as the damage is cosmetic. Suckers arising at the base can be removed if you want a tidier, more open shrub.

Autumn: The foliage turns clear golden yellow, usually in October, and red drupes ripen on female plants. Prune only if needed, immediately after flowering rather than in autumn, since flower buds form on the previous season’s wood. Collect and sow seed straight away if you want to raise new plants.

Winter: Fully dormant and completely hardy, needing no protection. Young plants in exposed, windy sites benefit from a temporary windbreak in their first winter.

Best varieties to grow

Named selections are scarce, but the following are worth seeking out from specialist nurseries.

• Lindera benzoin ‘Rubra’ — a male form with unusual reddish-maroon flowers, giving a warmer tone to the early spring display.
• Lindera benzoin ‘Xanthocarpa’ — a female selection bearing golden-orange rather than scarlet fruit, striking against the yellow autumn foliage.
• Lindera benzoin ‘Green Gold’ — a heavy-flowering male clone chosen for an especially dense, generous spring bloom and reliable pollination.
• Lindera benzoin var. pubescens — the downy-leaved southern variant, slightly more tolerant of heat and humidity.

Pests, diseases and common problems

• Lime-induced chlorosis: leaves turn pale yellow between green veins on alkaline or dry soils. Mulch heavily with leaf mould or composted pine bark and apply chelated iron as a stopgap.
• Drought scorch and premature leaf drop: brown, crisped leaf edges from midsummer signal that the shallow roots have dried out. Water deeply rather than often, and maintain a permanent organic mulch.
• Laurel wilt: a fungal disease spread by the redbay ambrosia beetle causing sudden wilting and dieback, a concern in parts of the south-eastern United States. Remove and destroy affected wood promptly and avoid moving untreated firewood.
• Leaf spot and mildew: dark blotches or a grey bloom in still, crowded conditions. Thin congested stems after flowering to improve airflow and clear fallen leaves from beneath affected plants.