Sweet flag is a great wetland or boggy area plant. It is hardy to zone 3 and not really fussy about soil type. It does best with good rich soil but it will grow in other conditions. It cannot tolerate getting dry. Ideal for boggy areas, sides of streams or in ponds. Will spread rapidly once established and needs little if any care. The whole plant has a lovely aroma and the roots are edible. Not suitable for rain gardens as they tend to dry out at times. We don't think the deer eat it but cant be certain.
Description of Sweet Flag (Acorus calamus).
Sweet flag is a hardy wetland perennial plant with sword shaped leaves that
strongly resemble those of Iris plants but are greener. Their resemblance is
what gives this plant its common name 'sweet flag' as the leaves resemble the
yellow flag iris. However, the plant is not an iris, a rush or a sedge despite
its many common names.
Sweet flag has a spreading rootstock from which every spring a tuft of basal
leaves emerge. They are sword shaped, flattened with one wavy edge and a prominent
midrib with other parallel veins. These leaves are about ¾" (2 cm)
wide and up to 4 feet (122 cm) tall, and fairly bright green. In late spring
some leaves develop a 'flower' which is a cylindrical spadix, usually 2-4"
(5-10 cm) long and semi erect and just below the leaf tips. This spadix is covered
with tiny greenish yellow flowers in a diamond-shaped pattern. Flowers last
for about a month and are very sweet scented. Sweet flag is pollinated by insects,
which ones is not precisely known. However although these occur in the United
States and its original home in India and Asia they do not appear to be present
in Europe. Hence the plant does not produce fruit in that continent. Where it
is pollinated the fruit is a tiny greenish berry which is sparingly produced.
The whole plant is aromatic and emits a pleasant aroma when bruised. It is hardy
to zone 3.
Location and Care of Sweet Flag (Acorus calamus).
This is a wetland plant and needs water. It also needs full sun but will tolerate
a little shade especially in higher numbered zones (7 and higher) . It prefers
rich soil for the best growth but will grow in poorer soil but not as well.
It will grow in standing water, boggy soils or soils that are consistently moist.
It can be grown in any garden provided the water is provided for it, but it
is ideal for stream sides, ponds and wet areas. It is not recommended for rain
gardens as these often dry out during the year.
For best results ensure that the soil has plenty of organic material dug into
it. Plant out slightly below the soil surface in moist soils or at the water's
edge. The leaf tips will scorch if the soils dry out. Plant about 10 inches
(25 cm) apart. When established the plants will grow rapidly and spread out.
Plant spread will only be limited by the size of the wetland. If containment
is required plant in containers to prevent sweet flag from taking over the area.
Sweet flag is very hardy, easily to zone 3. It dies down and goes dormant every
winter. Provided that the plants do not dry out sweet flag needs almost no additional
care or maintenance. Just plant and enjoy.
Growing Sweet Flag (Acorus calamus) from seed.
Best grown in small pots with a few seeds per pot, depending on the size. Stand
pots in about 1 inch (3cm) of water to ensure they are constantly moist. Pot
up seedlings as soon as they are large enough to handle. Keep wet by standing
pots in shallow water and harden off outside. Once the plants are large enough
plant out in final location about 10 inches (25 cm) apart. As long as they are
kept moist they need very little additional care.
Pests and Problems with Sweet Flag (Acorus calamus).
There are
no serious insect or disease problems. Scorch will occur if soils
are not kept consistently moist to wet. The main problem is aquatic animals.
Muskrats love to eat the tubers. If you are planting in a wetland situation
these can be a major problem. At present we are unsure if deer eat them, they
have not eaten ours yet and they are outside our main deer fence. However they
are not on the 'deer route' and may just not have been discovered yet.
Harvesting Sweet Flag (Acorus calamus).
Roots. It is the root that is used for medicinal purpose. Rhizomes are usually
harvested during their second or third year when they are large enough and still
firm. Older rhizomes tend to become hollow. The best time is late autumn or
early spring. Roots must either be dug from the soil or raked up from ponds
and streams. Fresh rootstock is brownish red or white green with a spongy texture.
They have a sweet aroma and bitterish pungent taste.
Leaves. Leaves are also very aromatic and have long been used as a 'strewing'
herb. Placed on the floor to be walked upon these were often used in Religious
rituals and special occasions. Leaves can be harvested at any time during the
growing season provided they are large enough. Do not take all the leaves from
one plant as it will deplete the rhizome and it may not recover.
Edible uses of Sweet Flag (Acorus calamus).
The rhizome can be pealed and washed to remove the bitterness then eaten like
a fruit. It can also be roasted and used as a vegetable, or it can be candied
and used as dessert. The dried and powdered rhizome has a spicy flavour and
is used as a substitute for ginger, cinnamon and nutmeg.
The young leaves can be cooked and used as a vegetable or to flavor desserts
in the same way vanilla pods are used. The inner portion of the young stems
can be used in salads. The flowers are sweet and can be eaten raw.
Medicinal Uses of Sweet Flag (Acorus calamus).
Sweet flag has a very long history of use in herbal medicine. In Ayurveda it
is highly valued as a rejuvenator for the brain and nervous system and as a
remedy for digestive disorders. It is used internally in the treatment of digestive
complaints, bronchitis, sinusitis . It has been reported to be very useful in
stimulating and normalizing the appetite. In small doses it reduces stomach
acidity whilst larger doses increase stomach secretions and it is, therefore,
often used in the treatment of anorexia nervosa. Native Americans have long
used this herb. They would chew roots to increase energy and stamina. The roots
will act as both a stimulant and as a sedative allowing the body's energy to
be placed in balance. For this reason it is an excellent choice for treatment
of panic and anxiety attacks as well as for daily stress and anxieties. However
long term use can cause fatigue and exhaustion. Chewing the root is said to
kill the taste for tobacco and to clear the voice. However large doses can cause
nausea and vomiting. Bath oils containing calamus have caused redness of the
skin (erythema) and dermatitis, particularly in hypersensitive individuals.
Other uses of Sweet Flag (Acorus calamus).
Both the root and the leaves are sometime added to herbal smoking blends or
mixed with tobacco.
The leaves are used to make baskets or woven into mats. An essential oil is
made from the plant and used in perfumery and as a food flavouring. It can also
be used as an insect repellant and insecticide and added to rice it reduces
loss by insect damage. The dried leaves can also be used to line cupboards and
storage areas to repel insects and keep the area smelling sweet. It is also
burnt as incense.
Known Hazards of Sweet Flag (Acorus calamus).
The fresh root of some populations can be
poisonous. There are two different
forms of this plant. The triploid form of the species is found in Asia This
contains the compound asarone. This has tranquillizing and antibiotic activity,
but is also potentially toxic and carcinogenic. However the diploid form of
sweet flag found in North America and Siberia is free of these compounds. The
roots have been used in India for thousands of years with no reports of cancer.
In more recent times the essential oil has been extracted from the roots and
used in medicine. It appears that this concentrates the unwanted compounds so
the essential oil and roots should be avoided for medicinal use. It is also
recommended that only roots from known populations in North America or Siberia
be used to avoid any possible problems. Use sparingly so overdoses are not an
issue.
Synonyms---Calamus. Sweet Flag. Sweet Root. Sweet Rush. Sweet Cane. Gladdon. Sweet Myrtle. Myrtle Grass. Myrtle Sedge. Cinnamon Sedge. Calamus aromaticus