The botanical name for horse chestnut is Aesculus, which is the Latin name for a form of oak tree but adapted as a name for this genus.
The horse chestnut is widely grown and familiar to most people from childhood, and playing with conkers which are the large, shiny brown seeds of this tree.
The horse chestnut species is Aesculus hippocastanum. The word hippo means horse and castanum refers to the edible Spanish chestnut, used in some countries for roasting on hot coals when the chestnuts have been collected on the ground.
Spanish chestnut is a human food and horse chestnut is poisonous.
Aesculus has been used for centuries as a herbal medicine for treatment of a variety of ailments including gastric issues and circulation problems in the legs.
Family
The widely grown horse chestnut is part of the horse chestnut family, the Hippocastanaceae.
Although it might appear that the horse chestnut and the Spanish chestnut are so closely named that they might also be closely related, this is not the case. Neither of them are native trees.
The horse chestnut is much more widely grown, which is strange because it is of less value as timber or food. The timber of horse chestnut is relatively soft, while the timber of the Spanish is hard and resists rotting.
While horse chestnut has its own genus, Spanish chestnut is part of the Beech family, the Fagaceae.
The most attractive and arguably the most beautiful of all the chestnuts, is the Indian horse chestnut, Aesculus indica. There is also a Chinese species, Aesculus chinensis.
From North America, there are several species occasionally seen in gardens in Europe. They have been given the common name of buck-eye. These trees vary in size and can be much smaller than European or Asian species.
The red horse chestnut, Aesculus x carnea, is often seen in gardens. The word carnea means red like flesh. It is a smaller tree reflecting its parent, Aesculus pavia, which means small, and it has dark red flowers.
The hybrid form, which has the horse chestnut, as the other parent, comes true to type when sown, but a named cultivar, such as ‘Briotii’ would need to be grafted in propagation.
Garden value
As large trees go, it is little wonder that horse chestnut is one of the most popular because it is highly decorative with a fine show of large spikes of white flowers in spring and a show of good green colour slightly earlier.
But it is one of the best large trees for good foliage and became popular in the 1800s. The large sticky buds on stout, pale brown barked twigs added another dimension during the winter period.
Horse chestnut has been widely planted in avenues and more freely on old parkland where its speed of establishment could be used effectively.
Although it scores well for these various purposes, horse chestnut is not without its faults. When it gets to mature size, after about a century, it has an alarming tendency to drop large branches.
The Indian horse chestnut though does not grow as large and it would appear that its growth is more robust and less likely to run into trouble.
Growing horse chestnuts
There are two main considerations when planning to grow horse chestnut trees.
First of all, map out that there will be space for these big trees in years. Make sure that they are not planted in a dangerous position where branches might fall unexpectedly.
Secondly, horse chestnut is one of the easiest of trees to grow from seed. It has large seeds with a good store of plant nutrients to get young saplings off to a good start in pots or in the open ground.
Within a few months, it can be difficult to find a suitable location for future growth.
Being a tree of soft timber, it is wise to plant the trees where the drainage is good and trees are not likely to be over-supplied with moisture. Control weeds around young trees for several years.
Fruit, vegetables and herbs
A late crop of carrots could be sown, and will give small, tasty carrots late in the year if the weather is good; also consider salad vegetables that mature quickly.
Peas could still be sown. Plant out winter cabbage varieties, if not already done. As herbs begin to flower, they are ready for drying or freezing for storage.
Lawns
The weather has been very varied for lawns with a lot of cool and variably dry weather reducing growth. It is amazing how the ground dried out so rapidly after so much rain in spring.
Lawns fed earlier in the year probably do not need feeding now but keep edges trimmed.
Trees, shrubs and roses
The soil in many areas is still quite dry and young trees and shrubs, planted in the last year or so, should be checked for signs of drought.
If these plants are not showing new growth at the tips of the branches, they may be suffering. Early flowering shrub roses and ramblers could be pruned.
Flowers
Bedding plants in pots and baskets are now in need of regular watering and feeding. Because the roots have now filled the pots, watering has become more critical.
Feeding every two weeks or so is essential to keep the plants going after the first flush. Seeds of perennial flowers can be sown now.
Greenhouse and house plants
Continue watering and feeding greenhouse plants. Be certain to water plants in pots or grow-bags regularly. These can easily dry out, leading to blossom end rot.
Train and side-shoot tomatoes and cucumbers. Take summer cuttings of fuchsia, magnolia, rose and clematis.