The most magnificent horse chestnut is Aesculus parviflora: the bottlebrush buckeye. This native shrub attracts pollinators extraordinarily. I planted it several years ago along a sunny fence; it now takes up an area about 20 feet long by 10 feet wide.
It blooms June to July with beautiful candelabra-like white flower spikes that are abuzz with all kinds of native bees and beneficial flies. The peachy-pink pollen exudes a delicate fragrance into the air.
The flower spikes are followed by smooth red-brown chestnut-like seeds. Beautiful but not edible for humans, the seeds are valued by many small mammals and insects. The horse chestnut’s native range is southern Virginia to Georgia and eastern Alabama and Tennessee, but it does very well in Maryland.
Aesculus sylvatica is the painted buckeye. It likes partial shade to sun and has similar growth habits to the bottlebrush buckeye. The flowers have shades of yellow, red, green and pink and are four- to eight-inch-long clusters in mid-spring.
Aesculus pavia is the red buckeye. It likes moist, well-drained soil in sun to shade. It has a shrubby habit, forming a rounded mound about 20 feet high and wide. The red flowers are an inch and a half long, tubular and form four- to eight-inch-long terminal clusters in mid-spring. The fruit has a smooth husk, splitting open to release one or two glossy brown seeds. In flower, this plant is a hummingbird magnet. Its natural range is the coastal plain from North Carolina to Florida and Texas.
Aesculus glabra is the Ohio buckeye, which is a large tree up to 75 feet high that grows in sun to partial shade. The flowers are greenish yellow and tubular in a four- to seven-inch-long terminal stalk. The fruit is a prickly husk that splits open to release seeds that are glossy and rich brown. Its natural range is western Pennsylvania throughout the middle states.
Don’t confuse these native species with Aesculus hippocastanum, the medicinal horse chestnut that is native to the Balkans and western Asia. The Turks used those nuts to treat respiratory ailments in horses. Today, extracts are made into standardized horse chestnut pills used to treat hemorrhoids and varicose veins. It is anti-inflammatory, astringent and internally strengthening to the blood vessels.
The seeds of all Aesculus species are poisonous.
Maria Price-Nowakowski runs Beaver Creek Cottage Gardens, a small native plant nursery in Severn.