Tutsan
Also known as
Sweet-amber, Androseme, St. John’s wort (tutsan)
Keep this plant’s care guide close at hand.
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Hypericum androsaemum, commonly called tutsan, is a small, bushy, semi-evergreen shrub in the St. John’s wort family. Reaching about 0.6–1.2 m tall and wide, it bears oval, aromatic, opposite leaves and clusters of starry yellow flowers in early to mid-summer. After flowering, showy berries develop, changing from pale green to bright red and finally glossy black, making the plant highly ornamental and popular in cut-flower work. It thrives in woodland edges and hedgerows where soils remain evenly moist but well drained. Tutsan is hardy in temperate climates and tolerates a range of soils from light to moderately heavy. Birds often eat the ripe berries, aiding seed dispersal. While associated with St. John’s wort, it’s less aggressive than some congeners, though it can naturalize and is invasive in parts of New Zealand and locally elsewhere. Historically used in folk remedies, all parts—especially berries—are considered mildly toxic if ingested.
Taxonomy
Properties & Requirements
How to care for Tutsan
Water
Water regularly during the first growing season to establish a deep root system—about 2.5 cm per week from rain or irrigation. Once established, tutsan tolerates short dry spells but performs best with evenly moist soil. Allow the top 2–4 cm of soil to dry between waterings in containers; in-ground plants may need supplemental water during prolonged heat. Avoid standing water and poorly drained sites, which invite root issues. Mulch helps reduce watering frequency.
Light
Full sun to partial shade. In cool, maritime climates, full sun produces sturdy growth and abundant flowers. In warmer regions or inland sites, morning sun with afternoon shade reduces heat stress and preserves foliage quality while still giving a good berry set. Deep shade reduces flowering and fruiting, while intense all-day sun in hot climates may scorch leaves and dry soil rapidly. Aim for 4–6 hours of direct light for a balanced display.
Nutrients
Tutsan is not a heavy feeder. Incorporate compost or well-rotted leaf mold into the root zone in early spring and apply a 3–5 cm organic mulch to conserve moisture and add nutrients. If growth is weak, use a balanced, slow‑release fertilizer (e.g., 8‑9 month 10‑10‑10 or 12‑12‑12) lightly in spring, following label rates. Avoid high nitrogen that promotes lush, floppy growth at the expense of flowers and fruit. Container plants benefit from a light liquid feed in late spring and midsummer.
Temperature
Hardy in roughly USDA Zones 6–9. Ideal growth occurs between 10–25°C. Established plants tolerate winter lows to about −15°C with mulch protection, though foliage may be shed in severe cold. In hot summers, sustained heat above 32°C can stress plants; provide afternoon shade and consistent soil moisture. Avoid warm, stagnant microclimates that combine high heat with drought. Container specimens should be protected from hard freezes by sheltering or insulating pots.