Acorus aka Sweet Flag or Calamus Root

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Acorus

Acorus

Acorus g. 'Ogon' (4) 1-gallons

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Acorus

Acorus g. 'Ogon' (3.5 inch pot)

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Acorus

Acorus g. 'Ogon' (18)ct Flat

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Acorus

Acorus g. 'Ogon' (4) 1-gallons

Acorus gramineus 'Ogon' (4) 1-gallons Common name: Golden sweet flag, golden Japanese sweet flag, or Japanese rush (a.k.a. 'Wogon'). Zone: (5) 6 to 10, evergreen in warm zones. Sun to part...

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Acorus

Acorus g. 'Ogon' (3.5 inch pot)

Acorus gramineus 'Ogon' (3.5-inch pot)Common name: Golden Variegated Sweet Flag Height: 8-12 Inches Spread: 6-12 Inches Hardiness Zone: 5/6-10 Sun to Part-Shade Prefers afternoon shade in...

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Acorus

Acorus g. 'Ogon' (18)ct Flat

Acorus gramineus 'Ogon' (18)ct Flat Common name: Golden sweet flag, golden Japanese sweet flag, or Japanese rush (a.k.a. 'Wogon'). Zone: (5) 6 to 10, evergreen in warm zones. Sun to part shade,...

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Now: $127.64
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Acorus: Zones, Characteristics, and How to Use Them in Your Landscape

Acorus, commonly called sweet flag, is a genus of perennial plants known for their iris-like foliage and adaptability to wet conditions. The most popular variety for landscaping is Acorus gramineus, which comes in green and variegated forms.

Zones

Acorus gramineus is a versatile plant that thrives in USDA Plant Hardiness Zones 5 to 9. This means it can tolerate winter temperatures as low as -20°F (-29°C) to 20°F (-6°C). However, there's a slight caveat. In the northernmost reaches of zone 5, the foliage might not be evergreen and could die back in winter.

Characteristics

Acorus gramineus has several attractive characteristics that make it a valuable addition to the landscape:

Foliage: The main attraction of Acorus is its sword-shaped foliage. The green variety has lush, green blades, while the popular 'Ogon' cultivar boasts bright yellow and green striped leaves. Both types add a textural element to the garden and provide year-round interest, especially in warmer climates where the foliage remains evergreen.
Habit: Acorus forms clumps that slowly spread over time by underground rhizomes. This makes it a good choice for groundcovers or edging ponds and streams.
Flowers: While not particularly showy, Acorus produces small yellow-green flowers in late spring or early summer. The flowers are borne on inconspicuous spikes and are not a major ornamental feature.
Wet soil tolerance: Acorus thrives in moist to wet soils and can even tolerate boggy conditions. This makes it a perfect choice for rain gardens or planting around ponds.
Low maintenance: Once established, Acorus requires minimal care. It's generally pest- and disease-resistant and doesn't need frequent dividing.

How to Use Acorus in the Landscape

Acorus' versatility allows it to be used in various landscape settings. Here are some ideas:

Bog gardens: Acorus is a natural fit for bog gardens, where its moisture-loving nature thrives. Plant it alongside other bog plants like irises, rushes, and ferns for a lush and colorful display.
Pond margins: Acorus adds a touch of elegance to the edges of ponds and streams. Its green or variegated foliage creates a beautiful contrast with the water and complements other water-loving plants like cattails and bulrushes.
Groundcover: Acorus is a low-growing, slow-spreading groundcover that helps suppress weeds. Use it in areas with moist soil, such as under trees or around shrubs.
Borders: The upright, sword-like foliage of Acorus adds a nice vertical element to garden borders. Plant it at the back of the border to provide a backdrop for shorter flowering plants.
Containers: Acorus can also be grown in containers, provided the pot has good drainage holes and is kept consistently moist. This is a great option for patios, balconies, or other areas where you want to add a touch of greenery.

When planting Acorus, choose a location that receives full sun to part shade. Amend the soil with compost or other organic matter to improve drainage and moisture retention. Water your Acorus regularly, especially during hot, dry weather.

With its beautiful foliage, adaptability to wet conditions, and low-maintenance requirements, Acorus is a valuable addition to any landscape. So if you're looking for a versatile plant that can add interest and texture to your garden, consider planting Acorus.

Acorus Care Guide: Spacing, Water, Sunlight, Soil, and More

Acorus, with its sword-like foliage, is a popular choice for gardeners thanks to its ease of care and adaptability. But to ensure your Acorus thrives, here's a breakdown of its specific needs:

Spacing:

Acorus spreads slowly through underground rhizomes.
When planting multiple plants, space them 12-18 inches (30-45 cm) apart to allow for future growth.
If using them as a groundcover, plant closer (8-12 inches or 20-30 cm apart) to create a dense mat.

Watering:

Acorus is a moisture lover.
Aim to keep the soil consistently moist, especially during the growing season.
During hot weather, you might need to water daily.
A good indicator is to stick your finger an inch or two into the soil. If it feels dry, it's time to water.
They can tolerate periods of short drought, but the leaves might wilt.

Sunlight:

Acorus is adaptable to light conditions.
It prefers full sun to part shade.
In very hot climates, afternoon shade can be beneficial to prevent leaf scorch.
Avoid deep shade, as this can lead to leggy growth and less vibrant foliage.

Soil:

Acorus thrives in moist to wet soils.
Ideal soil is fertile, well-draining, and slightly acidic (pH 6.5-7.5).
If your soil is heavy clay, amend it with compost or other organic matter to improve drainage.
They can tolerate standing water for short periods but avoid constantly soggy soil.

Fertilizing:

Acorus is not a heavy feeder.
A light application of balanced fertilizer in spring is sufficient.
You can also use compost mulch around the base of the plant to provide sustained nutrients.

Pruning:

Acorus requires minimal pruning.
Simply remove any dead, diseased, or brown leaves throughout the growing season to maintain a tidy appearance.

Pests and Diseases:

Acorus is generally pest- and disease-resistant.
In rare cases, they might be susceptible to snails or slugs, which can be controlled with organic methods.

Overwintering:

In colder climates (zones 5-6), the foliage might die back in winter.
Don't worry, it's likely to return in spring.
You can add a layer of mulch around the base of the plant in fall to provide additional winter protection.

Dividing:

Acorus can be divided every 3-4 years to control its spread or propagate new plants.
The best time to divide is in early spring or fall.

By following these simple care tips, you can keep your Acorus happy and healthy for years to come.

Acorus’s Flower Colors, Forms, Bloom Time and Pollinators

Acorus is primarily prized for its beautiful foliage, and the flowers are not particularly showy. Here's a breakdown of what you can expect:

Flower Colors:

Acorus gramineus produces small, inconspicuous flowers in late spring or early summer (May to June).
The flowers are typically a greenish-yellow color and borne on short spikes that emerge from the base of the plant.
They don't have petals and are not fragrant.

Varieties:

There are no specific varieties known for particularly vibrant or showy flowers. Acorus varieties are mainly cultivated for their foliage variations, such as:

Acorus gramineus ‘Ogon’: This popular variety has bright yellow and green striped leaves.
Acorus gramineus ‘Variegatus’: This type has green leaves with creamy white variegation.

Bloom Time:

The bloom time for Acorus gramineus is relatively short, lasting only a few weeks in late spring or early summer (May to June).

Pollinators:

Due to their small size and inconspicuous nature, Acorus flowers are not particularly attractive to pollinators like bees or butterflies.
The pollen-less flowers don't offer nectar rewards, so they are not a significant draw for pollinators.

Summary:

While the flowers of Acorus aren't a major ornamental feature, the plant makes up for it with its attractive foliage, ease of care, and adaptability to various garden conditions.

Acorus’s Latin Name Pronunciation, Common Names and Botanical Names

Latin Name Pronunciation:

Acorus (ah-KOHR-us)

Here's a breakdown of the pronunciation:

Aco (ah-KOH): The "a" is pronounced like the "a" in "father." The "co" is pronounced like "koh" with a slight rounding of the lips.
rus (us): The "us" is pronounced like the "us" in "bus."

Common Names:

Acorus gramineus has several well-known common names:

Sweet flag: This is the most common name and refers to the plant's fragrant rhizomes.
Calamus: Another common name derived from the Greek word for "reed."
Waterflag: This name reflects the plant's preference for wet environments.
Baldwin's ironwort: An older, less common name.

Botanical Names:

Acorus gramineus: This is the most common and accepted scientific name for the species.
- "Acorus" is the genus name, as discussed earlier.
- "Gramineus" (gram-IN-ee-us) is the species epithet, derived from the Latin word "gramen" meaning "grass," likely referring to the grass-like leaves.

Here's a quick tip for remembering the pronunciation of "gramineus": Think of "gram" like a unit of weight and combine it with "in-between-us."

Acorus’s Critter, Pest and Disease Resistance

Acorus is generally considered a low-maintenance plant with good resistance to pests and diseases. Here's a breakdown of what you can expect:

Critters:

Deer and rabbits: Acorus is not typically palatable to deer or rabbits. The rhizomes have a strong, pungent odor that deters these herbivores.
Snails and slugs: In very moist conditions, Acorus might be susceptible to snails and slugs that munch on the leaves. You can control them with organic methods like beer traps, handpicking, or introducing beneficial nematodes.

Pests:

Acorus is generally pest-free.
There are no major insect pests that specifically target this plant.

Diseases:

Acorus is also relatively disease-resistant.
Fungal diseases like crown rot might occur in poorly drained soils. Ensuring proper drainage and avoiding overwatering is key to prevent such issues.
Bacterial diseases are very uncommon with Acorus.

Overall:

Acorus's biggest advantage is its resilience. The strong-smelling rhizomes and lack of appealing foliage make it unattractive to most pests. Fungal diseases are the main concern, but proper drainage mitigates that risk.

Planting Acorus

Before Planting:

Timing: Ideally, plant your bare root Acorus in early spring or fall when the soil is cool and moist. Avoid planting during hot summer months.
Inspect the roots: Check the roots for any damage or rot. Healthy roots should be firm and light brown.
Hydration: If the roots are dry, soak them in a bucket of water for 12-24 hours before planting. This helps rehydrate the root system and promotes good establishment.

Planting:

Location: Choose a planting site that receives full sun to part shade. Acorus thrives in moist to wet conditions, so it's perfect for bog gardens, pond edges, or areas with consistently damp soil.
Digging the hole: Dig a planting hole 2-3 times wider than the root spread of your Acorus and just deep enough to accommodate the roots.
Amending the soil (optional): If your soil is heavy clay, amend it with compost or other organic matter to improve drainage. Acorus can tolerate some standing water, but constantly soggy soil can lead to problems.
Positioning the plant: Gently place your Acorus in the hole, spreading the roots out. Ensure the crown (the area where the roots meet the base of the stems) sits at soil level.
Filling the hole: Backfill the hole with the excavated soil, gently tamping it down to remove air pockets.
Watering: Water thoroughly after planting to settle the soil around the roots.

Aftercare:

Watering: Keep the soil consistently moist, especially during the first few weeks after planting. Water deeply when the top inch of soil feels dry.
Mulching: Apply a layer of organic mulch (around 2-3 inches thick) around the base of the plant to retain moisture, suppress weeds, and regulate soil temperature.
Fertilizing: Acorus is not a heavy feeder. A light application of balanced fertilizer in spring is sufficient. Alternatively, you can use compost mulch for sustained nutrient release.

First Year Tips:

Monitor moisture: Be especially attentive to watering needs during hot, dry periods in the first year to ensure proper establishment.
Limited flowering: Don't expect a big flower display in the first year. Acorus typically flowers in its second year or later.
Winter protection (optional): In colder climates (zones 5-6), the foliage might die back in winter. You can add a layer of mulch around the base of the plant in fall for extra winter protection.

By following these steps and providing good care in the first year, your bare root Acorus should establish itself well and thrive for many years to come.

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Acorus

Acorus g. 'Ogon' (4) 1-gallons

Acorus

Acorus g. 'Ogon' (3.5 inch pot)

Acorus

Acorus g. 'Ogon' (18)ct Flat

Acorus

Acorus g. 'Ogon' (4) 1-gallons

Acorus

Acorus g. 'Ogon' (3.5 inch pot)

Acorus

Acorus g. 'Ogon' (18)ct Flat

Acorus: Zones, Characteristics, and How to Use Them in Your Landscape

Acorus Care Guide: Spacing, Water, Sunlight, Soil, and More

Acorus’s Flower Colors, Forms, Bloom Time and Pollinators

Acorus’s Latin Name Pronunciation, Common Names and Botanical Names

Acorus’s Critter, Pest and Disease Resistance

Planting Acorus