Horse chestnut trees (Aesculus hippocastanum) grow thick and tall, adorned with snowy-white flowers in the spring. From midsummer to fall, the horse chestnut flowers develop into green seedpods. These trees have twisted limbs, with bark that grows in a circular pattern. To grow a horse chestnut tree from seed requires only a few steps. Plant two trees so they can cross-pollinate if you want them to produce nuts.
Acquire a horse chestnut seed either from a reliable seller or from a nutting tree. The easiest way to find fertile nuts is to locate a grove of horse chestnut trees that have pollinated one another. Collect the spiky burs that have fallen on the ground. Unpollinated burs will contain small and shrivelled nuts that will not sprout.
Place horse chestnut burs in a plastic bag with moist peat moss; poke holes in the bag to promote air circulation and prevent mould. Refrigerate the burs in the bag for three months.
Mix peat moss, sand and mulch to make a well-draining soil and place in the planting pot. Remove the spiky burr and put the chestnut on its side, one and a half inches deep into the soil, and cover. Locate a sunny, warm place where the container will not be knocked over and leave it there to germinate, watering regularly.
The germinating seed will first display two simple leaves on a single stalk. Wait until the seedling leaves fall off and the horse chestnut develops larger leaves with seven distinct segments. The tree is ready to transplant to its permanent location when it is about four months old and about eight inches tall.
Locate a good planting location for the seedling. Make sure the location is sunny with well-drained soil and plenty of moisture. The horse chestnut grows in U.S. Department of Agriculture Hardiness Zones 3 through 8, but prefers colder climates and may grow slower in warmer climates.