Plant of the Week: Virginia marsh-St. John's-wort

Triadenum virginicum, also referred to as Hypericum virginicum and by its common name Virginia marsh-St. John's-wort is a perennial plant. This marsh herb belongs to the Clusiaceae family. Marsh St. John's wort is most prevalent in New England. However, its native range extends down the eastern seaboard from Canada through Florida and stretches west to Mississippi. In the South, this plant can be found growing as far west as Texas. Specific places T. virginicum likes to grow are swamps, bogs, wet meadows, on the shores of rivers and lakes, and in interdunal swales. Interdunal swales are depressions between sand dunes filled with water, making them Triadenum virginum's ideal growing ground.

Photo by Ayinde Listhrop.

Triadenum virginicum usually grows from ten to eighteen inches tall. The smooth green leaves are sometimes tinged with red and are paler underneath. The leaves are opposite, meaning they grow directly across from each other rather than staggered along the stem. The flowers have five petals, ranged from white to pink to red, and grow in clusters. The Triadenum virginicum growing in the park were recently planted and have not bloomed yet. Normally, these plants flower in July and August. They're lovely to look at, and the brightness of the budding flowers as they sway in the breeze can easily snatch a person's attention and admiration as they walk pass.

Photo by Ayinde Listhrop.

PLANTING TIP:
Triadenum virginicum can grow in different soil types, but it needs plenty of water. After planting, it need to be watered at a slow pace, and the water must go deep into the soil. The amount of sun and shade it gets also needs to be monitored. T. virginicum cannot be in the sun too long or the leaves will scorch, while too much time in the shade will lessen the number of flowers it produces.

WHERE TO FIND THIS PLANT:
Triadenum virginicum is located in the Diller - von Furstenberg Sundeck & Water Feature of the High Line, between 14th and 15th Streets.


The High Line's planting design is inspired by the self-seeded landscape that grew up between rail tracks after the trains stopped running in the 1980s. Today, the High Line includes more than 500 species of perennials, grasses, shrubs, and trees – each chosen for their hardiness, adaptability, diversity, and seasonal variation in color and texture. Some of the species that originally grew on the High Line's rail bed are reflected in the park landscape today. Every week we share one of our gardeners' current favorites with you.

Our horticultural team counts on members and friends like you to help keep the High Line beautiful and thriving. Join our community of supporters who play an essential role in the High Line's most important gardening projects.


TD Bank is the Presenting Green Sponsor of the High Line.

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