perennialN. America Native

Slender Yellow Woodsorrel

Oxalis dillenii

The Story

Plant Bio

Oxalis dillenii is a low-growing, herbaceous annual or short-lived perennial native to North America, characterized by its trifoliate, heart-shaped green leaves. The plant produces small, bright yellow flowers from spring through fall, which open in full sun and close under cloudy conditions or at night.

This species is distinguished from similar yellow woodsorrels by the fine, flat-lying (appressed) hairs on its stems and the white-tipped ridges on its seeds. Under high light stress, the foliage often develops bronze or purplish undertones.

Uses & Benefits:

Provides a low-growing, bright yellow floral display over a long season from spring to autumn.

Functions as a quick-growing, opportunistic groundcover in dry, disturbed soils where other plants struggle.

Provides nectar and pollen for small native bees, beneficial insects, and occasional butterflies.

Essentials

At a Glance

Plant Type

Perennial

Height

16"

Width

12"

Light

Full Sun, Partial Sun

Zones

4, 5, 6, 7, 8, 9

Water

Moderate

Humidity

High

Lifespan

Short-lived perennial

Native To

North America

Toxicity

Toxic to pets and livestock

Bloom period

Spring – Fall

In flower about 9 months of the year

Planting

How to Grow

Select a site with well-drained sandy, loamy, or clay soil in full sun to partial shade.
Sow seeds directly onto the soil surface in spring, pressing them lightly into the substrate without burying them.
Water moderately to keep the soil damp but never waterlogged during the initial establishment phase.
Allow the plant to spread naturally via rooting stem nodes, monitoring the perimeter to contain unwanted spread.

Pro Tip

To prevent aggressive self-seeding, hand-pull plants or clip flowering stems before the cylindrical seed capsules mature and explosively eject their seeds.

Keep It Thriving

Care Guide

Do

Grow in well-drained soil to prevent root rot.
Hand-pull unwanted plants before seed capsules mature.
Provide full sun to maximize flower opening.

Don't

Do not overwater or plant in heavy, waterlogged muck soils.
Do not apply routine fertilizers, which encourage aggressive, weed-like spreading.
Do not shear old woody bases aggressively, as the plant behaves as a herbaceous annual or perennial.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Pest Check
Propagate
Prune
Spring Cleanup

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Naturalized AreasWildflower GardensGroundcover

Companion Plants

Viola sororia Sisyrinchium angustifolium Carex pensylvanica

Multiply

Propagation Methods

Good to Know

Common Questions

Slender Yellow Woodsorrel questions

What zones can Slender Yellow Woodsorrel grow in?

Slender Yellow Woodsorrel is hardy in USDA Zones 4–9. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Slender Yellow Woodsorrel deer resistant?

Not reliably. Deer may browse Slender Yellow Woodsorrel, especially tender spring growth — plan on repellents or fencing where pressure is high.

When does Slender Yellow Woodsorrel bloom?

Slender Yellow Woodsorrel typically blooms in spring through fall. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Slender Yellow Woodsorrel need full sun?

Slender Yellow Woodsorrel does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Slender Yellow Woodsorrel drought tolerant?

Yes — once established (usually after the first full season), Slender Yellow Woodsorrel handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.