annual

Corn Speedwell

The Story

Plant Bio

Veronica arvensis, commonly known as corn speedwell, is a low-growing winter annual herb native to Europe and Western Asia that has naturalized widely across North America. It forms loose mats of hairy, branching stems from a slender taproot, bearing opposite, coarsely toothed leaves on the lower stems and alternate, bract-like leaves above.

The species is distinguished by its tiny, solitary, pale blue to lavender flowers that measure only two to three millimeters across and nestle in the upper leaf axils. These blooms give way to characteristic heart-shaped seed capsules that facilitate its rapid spread in disturbed soils.

Uses & Benefits:

None; the flowers are minute and the plant is considered a garden weed.

Acts as a temporary ground cover on disturbed soils, though it is generally unwanted.

Provides a minor source of nectar and pollen for small native bees and generalist pollinators.

Essentials

At a Glance

Plant Type

Annual

Height

16"

Width

10"

Light

Full Sun, Partial Sun

Zones

4, 5, 6, 7, 8

Water

Low to Medium

Humidity

Tolerant

Lifespan

Annual

Native To

Europe, Western/Central Asia, Macaronesia, Northwest Africa

Toxicity

Non-toxic

Bloom period

Spring – Summer

In flower about 6 months of the year

Planting

How to Grow

Identify young seedlings in late winter or early spring by their light green, hairy, egg-shaped leaves with rounded teeth.
Hand-pull or hoe the shallow-rooted plants before the tiny blue flowers transition into heart-shaped seed capsules.
Avoid composting any pulled plants that carry mature seed pods to prevent reinfestation.
Establish a dense groundcover or apply mulch over bare soil areas to block future seed germination.

Pro Tip

Because this species relies entirely on a persistent soil seed bank to regenerate each fall, maintaining a dense, unbroken turf canopy or applying a thick layer of mulch is far more effective for control than pulling plants after they have already dropped their seeds.

Keep It Thriving

Care Guide

Do

Hand-pull small infestations early in the spring before seed set.
Maintain a thick, healthy lawn or mulch layer to crowd out emerging seedlings.

Don't

Do not add mature, seeding plants to compost piles.
Do not apply supplemental fertilizer, as this weed thrives in low-nutrient soils without assistance.

Seasonal Care Calendar

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

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

None (managed as an agricultural and turf weed)

Multiply

Propagation Methods

Good to Know

Common Questions

Corn Speedwell questions

What zones can Corn Speedwell grow in?

Corn Speedwell is hardy in USDA Zones 4–8. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

When does Corn Speedwell bloom?

Corn Speedwell typically blooms in spring through summer. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Corn Speedwell need full sun?

Corn Speedwell does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Corn Speedwell drought tolerant?

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