Detailed Guide to Making a Dwarf Sweet Flag Bonsai

Dwarf sweet flag, also known as fragrant sweet flag, is an evergreen perennial herbaceous plant with a rhizomatous root system in the Araceae family, belonging to the genus Acorus. It has a short, compact form with fine, sword-shaped leaves, fresh and green, pleasing to the eye, highly adaptable, vigorous in growth and easy to manage. Made into a miniature bonsai, it is rustic and elegant.

Dwarf sweet flag is usually propagated by division, which can be done each year from March to April or from September to October. When dividing, first tip the sweet flag out of the pot, wash the mud and sand off the roots, then split the root base apart by hand and plant it in a miniature porcelain pot or purple clay pot. For potting soil, choose a loose sandy loam. After planting, water thoroughly and place in a shady spot, keeping it moist; it roots very easily.

Dwarf sweet flag likes a cool, moist environment and also tolerates partial shade. It fears direct strong sunlight, so it is best placed in a moist spot with scattered light in the morning and evening. In summer, when temperatures are high, daylight hours are long and sunlight is intense, take care to provide shade. Otherwise, because the pot is small and holds little soil, the leaves are easily scorched. If it can be exposed to dew at night, the leaves will stay emerald green. Dwarf sweet flag is slightly cold-tolerant; in northern regions, after the Frost's Descent solar term, it should be moved indoors for care to avoid cold damage. If indoor humidity can be maintained in winter, its leaves can stay verdant. Dwarf sweet flag likes moisture and dislikes drought. For routine watering, keeping the potting soil moist is appropriate; overwatering easily causes yellow leaves. In summer, when temperatures are high, the amount of watering can be increased as appropriate, following the principle of keeping the potting soil wet but not waterlogged; insufficient watering will affect the plant's growth. In winter, when temperatures are low, watering should be controlled, and it is best to keep the potting soil moist rather than wet. From April to May, during the plant's vigorous growth period, some diluted, well-rotted cake fertilizer water can be applied appropriately, but not too much, to avoid excessive growth that throws the growth proportions out of balance and reduces its ornamental value. Dwarf sweet flag tolerates pruning. Promptly cut out aged branches, leggy branches and overly dense branches to keep the plant's shape attractive. Cultivation practice has confirmed that the more the plant is pruned, the finer its leaf shape becomes. Therefore, by frequently cutting the leaf clumps short in summer, new leaves can grow thickly and appear smaller, achieving the ideal miniature bonsai effect.