Species

Acorus gramineusJapanese Sweet Flag

8 other cultivars

perennial

Pusillus Dwarf Sweet Flag

Acorus gramineus 'Pusillus'

The Story

Plant Bio

Acorus gramineus is a semi-evergreen, marginal aquatic perennial that forms a low, dense tuft of narrow, grass-like, glossy green leaves. Insignificant, yellowish-green flowers (spadixes) appear in late spring to early summer, but it is primarily grown for its foliage effect.

This cultivar is distinguished by its diminutive size and fine, delicate foliage, making it ideal for container planting and low-maintenance garden borders.

Uses & Benefits:

Provides lush, grassy foliage that enhances shaded garden areas.

Helps control soil moisture in wet, shady spots.

Supports local wildlife by maintaining healthy wetland-like conditions.

SpeciesAcorus gramineusJapanese Sweet Flag

Essentials

At a Glance

Plant Type

Perennial

Height

3 inches

Width

12 inches

Light

Full Sun, Partial Sun, Shade

Zones

5, 6, 7, 8, 9, 10

Water

Moist to wet soil

Humidity

Prefers high humidity

Lifespan

Perennial

Native To

Asia

Toxicity

Low toxicity if ingested

Planting

How to Grow

Tuck rhizomes into moist soil in spring.
Water regularly to keep soil consistently moist.
Mulch around plants to retain moisture and suppress weeds.
Divide clumps every 2-3 years in early spring.
Remove dead foliage in late fall for tidy appearance.
Place in shaded or partial sun location for best growth.

Pro Tip

Ensure moist, well-drained soil and partial shade for optimal growth.

Keep It Thriving

Care Guide

Do

Keep soil consistently moist 🌱
Mulch to retain moisture and control weeds
Divide in early spring every 2-3 years
Place in partial shade for best vigor

Don't

Allow soil to dry out completely ❌
Expose to full sun in hot climates ❌
Over-fertilize, which can cause leggy growth ❌

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Divide
Fertilize
Plant
Spring Cleanup

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Shaded border with grassy foliageMoist garden bed for wet soils

Companion Plants

Japanese Iris Ferns Hostas Ligularia Carex

Multiply

Propagation Methods

Good to Know

Common Questions

Pusillus Dwarf Sweet Flag questions

What zones can Pusillus Dwarf Sweet Flag grow in?

Pusillus Dwarf Sweet Flag is hardy in USDA Zones 5–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Pusillus Dwarf Sweet Flag deer resistant?

Yes — Pusillus Dwarf Sweet Flag is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does Pusillus Dwarf Sweet Flag bloom?

Pusillus Dwarf Sweet Flag typically blooms in late spring to early summer through late spring. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Pusillus Dwarf Sweet Flag need full sun?

Pusillus Dwarf Sweet Flag does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.