# St John's Wort (*Hypericum perforatum*) St. John's Wort is a bright yellow flower that grows in sunny fields and meadows. It is known for its healing properties and is often used in herbal medicine. - **Category:** [Plants](https://www.snappit.app/explore/categories/plant) - **Rarity:** Common - **Danger:** 1/5 · Very low - **Snaps:** 22 - **Habitat:** Fields, Meadows - **Also known as:** Klamath Weed, Saint John's Wort, Tipton Weed ![St John's Wort](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/%28MHNT%29_Hypericum_perforatum_flower_and_buttons.jpg&width=800) Photo: Didier Descouens, CC BY-SA 4.0 · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:%28MHNT%29_Hypericum_perforatum_flower_and_buttons.jpg) ## Appearance The St John's Wort has bright yellow, star-shaped flowers with five petals, often adorned with tiny black dots. Its oval leaves appear to have tiny transparent holes when held to the light, a unique feature. ## Taxonomy - **Kingdom:** Plantae - **Phylum:** Tracheophyta - **Class:** Magnoliopsida - **Order:** Malpighiales - **Family:** Hypericaceae - **Genus:** Hypericum ## Interesting facts - Animals with white fur can get sunburned from eating too much of it! - Hold a leaf to the sun; it looks like it's full of tiny holes! - Some beetles are specially adapted to only eat St John's Wort! - Squeeze its flower buds to see them 'bleed' a surprising red juice! ## Special abilities - **Red Ink Protector:** St John's Wort can release a dark red liquid when its flowers or buds are crushed, which helps it defend against hungry insects. - **Sun Sensor Leaves:** St John's Wort has translucent dots on its leaves that act like tiny windows, possibly helping it regulate light or store oils. - **Toxin Shield:** St John's Wort produces special chemicals, like hypericin, that protect it from being eaten by many herbivores. ## Measurements & details - **Height:** 30-90 cm - **Spread:** 30-60 cm - **Flower Size:** 1-2.5 cm - **Bloom Season:** Summer - **Edible:** No - **Toxicity:** Moderate - **Lifecycle:** Perennial - **Pollination Method:** Insect ## Ecological connections - **Pollinates:** European honey bee (*Apis mellifera*) — Visits flowers for nectar and pollen - **Pollinates:** Buff-tailed bumblebee (*Bombus terrestris*) — An important pollinator of its flowers - **Eats:** St. John's wort beetle (*Chrysolina hyperici*) — Feeds on the leaves and flowers - **Eats:** St. John's Wort Aphid (*Aphis hyperici*) — Sucks sap from stems and leaves ## Traits - [Perennial](https://www.snappit.app/explore/traits/perennial): Perennial plants live for more than two years, typically returning to grow and bloom each year from their roots. - [Aromatic](https://www.snappit.app/explore/traits/aromatic): Aromatic plants produce and emit fragrant volatile organic compounds, often for defense or to attract pollinators. - [Flowering](https://www.snappit.app/explore/traits/flowering): Flowering plants are any plants that produce flowers as part of their reproductive cycle. - [Shade Tolerant](https://www.snappit.app/explore/traits/shade-tolerant): Shade tolerant plants are adapted to grow and thrive in areas with low light levels, requiring less direct sunlight. - [Medicinal](https://www.snappit.app/explore/traits/medicinal): Medicinal plants possess chemical compounds that can be used for therapeutic purposes to treat illnesses or maintain health. ## Collections - [Flowers](https://www.snappit.app/explore/collections/flowers) - [Plants](https://www.snappit.app/explore/collections/plants) ## Safety **Danger:** 1/5 · Very low While St. John's Wort is a beautiful plant, it's important not to pick or eat wild plants without adult supervision. ## Frequently Asked Questions ### How to identify St John's Wort? Count the petals where you can, then compare the flower's center, its symmetry, how the blooms are grouped and the leaves below. Color varies between garden varieties and shifts with the light. Flower Identifier: upload a photo and compare the visible details. ### How tall is St John's Wort? 30-90 cm ### How wide does St John's Wort spread? 30-60 cm ### How big are the flowers on St John's Wort? 1-2.5 cm ### When does St John's Wort bloom? Summer ### Is St John's Wort edible? No ### Is St John's Wort toxic? Moderate ### What is St John's Wort's lifecycle? Perennial ## Where to spot - [Ames Nowell State Park](https://www.snappit.app/guides/places/ames-nowell-state-park) — Massachusetts, US · State Park - [Berry Botanic Garden](https://www.snappit.app/guides/places/berry-botanic-garden) — Oregon, US · Botanical Garden - [Blackstone Boulevard–Cole Avenue–Grotto Avenue Historic District](https://www.snappit.app/guides/places/blackstone-boulevard-cole-avenue-grotto-avenue-historic-district) — Rhode Island, US · Historic District - [Cedarmere-Clayton Estates](https://www.snappit.app/guides/places/cedarmere-clayton-estates) — New York, US · Historic District - [Dayville Historic District](https://www.snappit.app/guides/places/dayville-historic-district) — Connecticut, US · Historic District - [Delaware Division of the Pennsylvania Canal](https://www.snappit.app/guides/places/delaware-division-of-the-pennsylvania-canal) — Pennsylvania, US · Historic Site [View all places to see St John's Wort](https://www.snappit.app/guides/where-to-see/st-johns-wort) ## More Plants - [white snakeroot](https://www.snappit.app/explore/white-snakeroot) (*Ageratina altissima*) - [tree-of-heaven](https://www.snappit.app/explore/tree-of-heaven) (*Ailanthus altissima*) - [western sword fern](https://www.snappit.app/explore/western-sword-fern) (*Polystichum munitum*) - [common milkweed](https://www.snappit.app/explore/common-milkweed) (*Asclepias syriaca*) --- Source: [St John's Wort: Facts & Places to See — Snappit](https://www.snappit.app/explore/st-johns-wort)