Native to central Asia, horse chestnut has been grown as a shade tree in North America since the 1700s. The common name “buckeye” comes from the appearance of its shiny reddish brown seeds, known as “conkers,” which resemble the eyes of a deer. People sometimes mistakenly think the horse chestnut is an edible species—confusing it with the true chestnut — but it is not, and it can be poisonous. Native American tribes crushed the fresh seeds and scattered them in the water when fishing; chemical compounds called saponins, present in the seeds, slowed or stunned the fish and made them easier to catch.
Common Names: Buckeye, Chestnut, Horse Chestnut
Description: Deciduous tree up to 60 feet tall with a broad, domed crown; palmate leaves; spikes of fragrant white flowers followed by spiny green fruits containing shiny reddish brown seeds
Hardiness: To Zone 3
Flowering: Spring to early summer
Parts Used: Seeds and bark
Range/Habitat: Native to central Asia, naturalized throughout temperate Northern hemisphere
Horse chestnut contains a substance called aescin, which helps strengthen and increase vein elasticity. Studies have shown horse chestnut seed extract to be highly effective for treating varicose veins and chronic venous insufficiency, a condition that causes blood to pool in the veins of the lower legs after standing or sitting. Practitioners also use it to treat hemorrhoids and edema (fluid retention).
Aescin diminishes the number of openings in capillary walls, helping to prevent fluids from leaking into surrounding tissue. For this reason, horse chestnut is a good topical treatment for bruises and sports injuries. Horse chestnut gels can reduce swelling and tenderness after an injury. The herb also has anti-inflammatory properties; herbalists sometimes recommend it to relieve arthritis pain, eczema, phlebitis, and other inflammation.
Caution: Raw, unprocessed horse chestnut bark, stems, seeds, and leaves can be toxic and should not be ingested. Horse chestnut preparations should not be used internally by pregnant women. External preparations should not be applied to broken skin.
The horse chestnut tree has a large, spreading canopy and fragrant white blooms. It makes an attractive shade tree for home landscapes and parks.
How to grow it
Fast-growing horse chestnut trees prefer well-drained, fertile soil in sun or partial shade. Plant the young trees or seeds in spring or fall. To speed germination, soak seeds in water for 24 hours prior to planting. Established trees require little care other than occasional pruning in late winter. Harvest the seeds (inside the prickly pods) and bark in fall.