General Plant Information (Edit)
Plant Habit: Herb/Forb
Sun Requirements: Full Sun
Full Sun to Partial Shade
Water Preferences: Wet
Wet Mesic
Mesic
Soil pH Preferences: Slightly acid (6.1 – 6.5)
Neutral (6.6 – 7.3)
Minimum cold hardiness: Zone 3 -40 °C (-40 °F) to -37.2 °C (-35)
Maximum recommended zone: Zone 6b
Plant Height: 3 to 6 feet
Flowers: Showy
Flower Color: Yellow
Bloom Size: 2"-3"
Flower Time: Summer
Suitable Locations: Bog gardening
Uses: Erosion control
Will Naturalize
Wildlife Attractant: Bees
Resistances: Deer Resistant
Rabbit Resistant
Flood Resistant
Toxicity: Other: foliage is sort of toxic to mammal herbavores
Propagation: Seeds: Stratify seeds
Pollinators: Bumblebees
Bees
Miscellaneous: Tolerates poor soil
Monoecious

Image
Botanical names
  • Accepted: Hypericum ascyron subsp. pyramidatum
  • Synonym: Hypericum pyramidatum

Photo Gallery
Location: Jenkins Arboretum in Berwyn, Pennsylvania
Date: 2018-11-04
a plant in mid-autumn close to a pond
Location: Jenkins Arboretum in Berwyn, Pennsylvania
Date: 2018-11-04
foliage
Comments:
  • Posted by ILPARW (southeast Pennsylvania - Zone 6b) on Nov 6, 2018 9:56 AM concerning plant:
    Great St Johnswort is a herbaceous species, not one of the woody ones. It is native to some of northeast North America and Eurasia. The American variety is H. ascyron pyramidatum that is native to southern Quebec to Minnesota to southwest Iowa and Northeast Kansas over to New Jersey & Pennsylvania, growing in moist to wet areas of open woods, thickets, streambanks, fens, and lowlands. Its yellow flowers are about 2 inches wide, have 5 distinct petals definitely separated from each other, with a large, light green pistil in the middle that has 5 styles on the end of the pistil, (most Hypericum have only 1 to 3 styles) and there are about 100 long stamens in the flower. The leaves are long and pointed of about 4 inches long by 1.5 inches wide and sessile or slightly clasped on the stems. It gets a pale yellow fall color. It is easy to grow in regular gardens. I have never seen this species sold in conventional nurseries. I've only seen one specimen so far in my life at Jenkins Arboretum in southeast PA along their big pond. The Mount Cuba Center in northern Delaware is supposed to have some. Looks like a good perennial to me.

« Add a new plant to the database

« The Plants Database Front Page

Today's site banner is by Baja_Costero and is called "Ocotillo in bloom"

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.