The non-native tree can be a bit messy and offers little in the way of vibrant fall foliage, but it makes an excellent choice to line streets or provide some shade from the sun. Considered both a shade and an ornamental tree, the horse chestnut features a lush, spreading canopy that’s more than capable of blocking sunlight while adding both visual interest and beauty to landscaping. The horse chestnut tree will lose its leaves seasonally. The fruit of the tree is a highly poisonous seed (the horse chestnut) that can be found inside a prickly husk. The seed is a spiny fruit that’s about two inches in diameter and contains one or two blackish, nut-like seeds. The oblong flower clusters feature a blotch of color at the base which starts out yellow and ends up more of a reddish color. The tree itself grows at a medium rate, and planters can expect height increases of approximately 12 to 35 inches per year depending upon the soil quality, age of the tree, location, and climate—although growth may be much slower in older trees or poor-quality soil. As it matures, the tree develops an exfoliating bark, with its outer bark peeling away to reveal orange bark underneath.
Light
This tree will thrive in both full sun and partial shade. It prefers a minimum of two to six hours of direct, unfiltered sunlight every day.
Soil
Tolerant of an array of soils, the horse chestnut will grow in acidic, loamy, sandy, alkaline, and silty loam soils. However, the soil should always be kept moist and well-drained.
Water
These trees do not tolerate excessively dry conditions and will grow best if the soil is kept moist. You’ll want to water thoroughly after planting, and then be sure to give the new plant a thorough soaking once a week during summer (unless rainfall is plentiful).
Temperature and Humidity
The horse chestnut tree will bloom between April and June. Young trees can be protected in winter with a commercial-grade tree wrap, which is recommended for at least the first two or three years of growth.
Fertilizer
Newly planted horse chestnut trees respond quite well to fertilizer. Granular, liquid, or stake-type fertilizers can be used. Organic fertilizers, such as manure, can also produce desirable results.
Propagating
Some Varieties of Horse Chestnut Trees
Baumann’s Horse Chestnut: Produces double white blooms, no nutsRed Horse Chestnut: Possibly native to Germany, shorter than the common horse chestnut
Pruning
The trees should be pruned either in the early spring before the sap starts to flow or in the fall after the leaves have dropped. Low branches should be removed, as well as crowded or crossing branches. As the tree matures, pruning every three to five years will help keep it in optimal shape.
