How much sun does Kalm's st. john's-wort need?

Kalm's st. john's-wort grows best in full sun conditions.

When does Kalm's st. john's-wort bloom?

Kalm's st. john's-wort blooms in July and August.

Where is Kalm's st. john's-wort native?

Kalm's st. john's-wort (Hypericum kalmianum) is native to IL, IN, MI, MN and 3 more states, per the World Checklist of Vascular Plants (Kew).

What pollinators does Kalm's st. john's-wort attract?

Kalm's st. john's-wort draws bees.

Kalm's st. john's-wort

Name: Pollinator Patch
Author: Pollinator Patch

Hypericum kalmianum

Last reviewed: September 2026

Toxicity unknown

Kalm's st. john's-wort (Hypericum kalmianum) 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

24"–36" H × 24"–36" W

Bloom

Jul, Aug

Native to

IL, IN, MI, MN and 3 more states

Pollinators

bees

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

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 Coastal Zone Eastern Great Lakes Lowlands

A compact rounded shrub with narrow blue-green leaves and bright yellow flowers with prominent tufted stamens through summer. Tolerates both wet and dry rocky sites without losing its neat form.

Wildlife value

Pollen-rich flowers are visited heavily by bumble bees and other native bees.

Common questions

How much sun does Kalm's st. john's-wort need?: Kalm's st. john's-wort grows best in full sun conditions.
When does Kalm's st. john's-wort bloom?: Kalm's st. john's-wort blooms in July and August.
Where is Kalm's st. john's-wort native?: Kalm's st. john's-wort (Hypericum kalmianum) is native to IL, IN, MI, MN and 3 more states, per the World Checklist of Vascular Plants (Kew).
What pollinators does Kalm's st. john's-wort attract?: Kalm's st. john's-wort draws bees.

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

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

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