How to Grow and Care for Sweet flag

Sweet flag, also known as Calamus, Myrtle Flag, Sweet Sedge, Flag Root, Sweet Rush

Sweet flag thrives best in wet or boggy soil conditions, mimicking its natural habitat around water margins. It is important to maintain consistent moisture, without which sweet flag may not grow optimally. Propagate by division, ensuring each section has part of the rhizome. Sweet flag is relatively low-maintenance and resilient to common pests and diseases, making its care straightforward.

Watering schedule: Once per day

Sunlight Requirements: Full sun

Toxic to Humans

In This Article

Planting and Growing Sweet flag

Toughness	High
Care Level	Medium
Care Difficulty	Easy
Lifespan	Perennial
Watering Schedule	Once per day
Sunlight Requirements	Full sun
Soil Type	Garden Soil
Soil pH	6-7.5
Planting Time	Spring, Fall
Hardiness Zones	4-11
Toxicity	Toxic to Humans

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Varieties of Sweet flag

Variegated sweet flag

Best suited to semi-aquatic gardens, the variegated sweet flag offers foliage accent and texture through flowers and berries. Named for its variegated leaf blades, the variegated sweet flag's parentage is unknown. Although low-maintenance, the variegated sweet flag is one of the slower-growing cultivars of its species. Gardeners can plant this cultivar in ponds and border gardens as ornamental grass.

Common Pests & Diseases

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The Toxicity of Sweet flag

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More General Info About Sweet flag

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Sweet flag is a perennial, semi-aquatic plant that thrives in moist, boggy conditions. It features a clump-forming habit with thick, rhizomatous roots. Lance-shaped leaves grow erect from the rhizomes, typically reaching 2 to 4 feet (60 to 120 cm) in height and 1 inch (2.5 cm) in width, exhibiting a bright green color. These foliage blades are notably fragrant when crushed. Sweet flag is suitable for shallow water settings, not exceeding 2 to 3 inches (5 to 7.5 cm) in depth, and can tolerate partial afternoon shade which may be preferred in hotter climates.