A drought tolerant garden doesn’t have to be treeless. While the pickings are slim, there is a selection of trees that, once established, are well adapted to deal with extended bouts of little to no water. One such tree is yellowhorn, a species that demands to be considered for any waterwise landscape. Yellowhorn is rare in cultivation – and also restricted in its natural distribution – but perhaps that will change as word gets around about this beautiful and resilient tree.
Xanthoceras sorbifolium is native to several provinces in northern China and has been cultivated in a number of places outside of China since at least the 1800’s. Its ethnobotanical value is well understood in China. Its leaves, flowers, and seeds are edible and medicinal, and the high oil content of its seeds make them useful for the production of biofuels. Researchers are also investigating the use of yellowhorn for ecological restoration in arid habitats where desertification is a concern.
yellowhorn in bloom
Yellowhorn is the only species in the genus Xanthoceras, but is one in a long list of trees and shrubs in the Sapindaceae family – a family that now includes maples and horse chestnuts. It is considered both a large shrub and a small, multi-stemmed tree. It reaches a maximum height of about 25 feet, but arrives there at a relatively slow pace. It tolerates a variety of soil types, but like most other drought tolerant plants, it prefers soils that don’t become waterlogged easily. Its leaves are long, glossy green, and compound, consisting of 9 – 17 leaflets. The leaves persist late into the year and turn yellow in the fall. However, late spring, when the tree is covered in flowers, is when this tree puts on its real show.
Large white flowers with yellow-green centers that turn maroon or red-orange as they age are produced on racemes at the ends of branches. Small, yellow, hornlike appendages between each of the five petals of the flowers are what gives the tree its common name. Flowering lasts for a couple weeks, after which fruits form, which are about 2.5 inches wide, tough, leathery, and somewhat pear shaped. In my experience, most of the fruits are eaten by squirrels long before they get a chance to reach maturity. The ones the squirrels don’t get will persist on the tree, harden, and eventually split open to reveal several large, dark, round seeds nestled in chambers within the fruit.
To truly appreciate this tree, it must be seen in person, especially in bloom. At that point you will demand to have one (or more) in your garden. The seeds are said to be delicious, so you should give them a try if you can beat the squirrels to them. For a more thorough overview of yellowhorn, check out this article from Temperate Climate Permaculture, and for more photos of yellowhorn in bloom, check out this post from Rotary Botanical Gardens.
Squirrel nesting in yellowhorn, getting ready to go after more fruits.
All photos in this post were taken at Idaho Botanical Garden in Boise, Idaho.
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I enjoyed that article. So there is a Yellowhorn tree at the Garden in Boise. I need to see that in the spring. Thanks Dan
There is one, and it is unfortunately in a location that most visitors don’t get to see. I will show it to you sometime, and hopefully you’ll get a chance to see it in bloom.
Hi Daniel. I’d love to see this one in bloom. It looks quite lovely. On a quick google search, I located a source in Medford, Oregon.
https://lebeaubamboo.com/Xanthoceras-sorbifolium-Flowering-Yellowhorn-Tree.php
Hi David. I’ll let you know when it flowers next year. It’s a great tree. Cool that you were able to find a source for them. Plant Select sent us seeds for one that’s supposed to have maroon flowers. We’ll see if we can get them to grow. 🙂