What kind of habitat does Hypericum majus prefer?

Large St. Johnswort grows in consistently moist to wet soils, such as marshes, wet meadows, bog edges, and shorelines, usually in full sun.

When does Hypericum majus bloom?

Large St. Johnswort blooms from June through September, with small yellow flowers appearing through the summer months.

What pollinators visit Hypericum majus?

Bees and beetles are the main visitors to Hypericum majus flowers, which offer pollen rather than nectar.

How much water does Hypericum majus need?

This plant does best with medium to consistently high soil moisture and does not tolerate prolonged dry conditions well.

Is Large St. Johnswort HOA-friendly?

Large St. Johnswort takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Large St. Johnswort

Name: Pollinator Patch
Author: Pollinator Patch

Hypericum majus

Last reviewed: August 2026

Hypericum majus, or large St. Johnswort, is a summer blooming forb of wet meadows, marshes, and pond edges across the northern and midwestern United States, flowering from June through September in full sun.

Toxicity unknown

Large St. Johnswort (Hypericum majus) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

Light

full sun

Water

medium

Size

4"–12" H × 2"–6" W

Bloom

Jun, Jul, Aug, Sep

Native to

CO, CT, IA, ID and 23 more states

Pollinators

bees, beetles

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 452 programs across 44 states, each with a link to the provider and the date we last checked it.

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Browse plants for this ecoregion

High Plains Central Great Plains Great Plains Western Corn Belt Plains Northern Forests Northern Lakes and Forests North Central Hardwood Forests Driftless Area Southeastern Wisconsin Till Plains Central Corn Belt Plains Southern Michigan/Northern Indiana Drift Plains Huron/Erie Lake Plains Northeastern Highlands Northeastern Coastal Zone Acadian Plains and Hills Eastern Great Lakes Lowlands

Large St. Johnswort is a low-growing annual wildflower that produces small yellow blooms from summer through early fall. This compact native forb stays under a foot tall and spreads modestly, making it suitable for naturalized areas and wildlife gardens.

Growing Large St. Johnswort

Grow Large St. Johnswort in full sun and medium water. Mature plants reach 4 to 12 inches tall and spread 2 to 6 inches wide. Expect low maintenance to keep it looking intentional in a front yard.

In an HOA neighborhood

Large St. Johnswort takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

Annual growth means gaps and bare spots
Wild appearance doesn't fit formal landscaping
May be perceived as weedy by neighbors

Wildlife value

The bright yellow flowers attract native bees and beetles during its long blooming period from June through September.

Common questions

What kind of habitat does Hypericum majus prefer?: Large St. Johnswort grows in consistently moist to wet soils, such as marshes, wet meadows, bog edges, and shorelines, usually in full sun.
When does Hypericum majus bloom?: Large St. Johnswort blooms from June through September, with small yellow flowers appearing through the summer months.
What pollinators visit Hypericum majus?: Bees and beetles are the main visitors to Hypericum majus flowers, which offer pollen rather than nectar.
How much water does Hypericum majus need?: This plant does best with medium to consistently high soil moisture and does not tolerate prolonged dry conditions well.
Is Large St. Johnswort HOA-friendly?: Large St. Johnswort takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.

Native range data from the World Checklist of Vascular Plants (Kew). Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

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