How to Grow Golden Chain Tree

Pros and Cons of Laburnum

Golden chain tree with pond and rhododendrons in background.

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Golden chain tree—laburnum—is a Goldilocks of the plant world, and not just in appearance. This member of the pea family grows best in a narrow range of USDA planting zones. Just like in the fairy tale, it does not like it too cold, but it does not like it too hot, either. It requires a climate that is "just right," especially if you demand an optimal floral display. Nor is this the only drawback to the plant. Golden chain tree is relatively rare due to its fussiness and to various other problems to which it is susceptible. Still, its beauty makes it well worth trying if you have a climate conducive to growing it.

One of the few locations in the United States where golden chain tree grows abundantly is Bar Harbor, Maine. This is no coincidence, since Bar Harbor, which sticks out into the North Atlantic, is an area known for its cool summers. A famous landscape architect, Beatrix Farrand (1872 to 1959), understood that the climate in Bar Harbor would be perfect for golden chain trees. She left a considerable horticultural impression: The word from the locals is that it was Farrand who introduced laburnum × watereri to those parts. Many residences and businesses still sport golden chain trees as specimen plants. These beauties are also commonly seen growing wild along a few stretches of road in the area.

Golden Chain Trees should be planted in the fall or early spring; they are relatively fast growers, gaining more than 24 inches per year.

Botanical Name Laburnum
Common Name Golden chain tree, bean tree, Waterer laburnum
Plant Type Deciduous tree
Mature Size 15 to 25 feet in height; spread can be similar but is often less
Sun Exposure Full sun 
Soil Type Well-drained, rich, with medium moisture
Soil pH Neutral to alkaline
Bloom Time Late spring
Flower Color Golden
Hardiness Zones 5 to 7
Native Area Southern Europe
Toxicity Highly toxic to humans and animals

Golden Chain Tree Care

This stunning beauty has golden-yellow flowers with which it drips in late spring. The racemes have a strong fragrance; compelling rather than sweet, it is an acquired taste. But everyone immediately falls in love with their bright, cheerful appearance. The golden blooms may be 10 to 20 inches in length. Young specimens require staking, as the trunks are quite floppy. 

Light

Pick a spot with full sun to plant your golden chain tree.

Soil

Well-drained soil that's acid or alkaline (pH 5.0 to 8.0) is best for your golden chain tree.

Water

Golden chain trees should be watered on a weekly basis. Be sure the water doesn't puddle at the base.

Fertilizer

Feed them fertilizer in early spring (one designed for flowering trees and shrubs, with a high acid content).

Is Golden Chain Tree Toxic?

Golden chain tree is a highly poisonous plant, so it is not a pet or child-friendly choice. All parts of the plant are toxic, especially the seed pods, because they contain cystine, a dangerously poisonous alkaloid.

Symptoms of Poisoning

In humans and pets, consumption can cause vomiting, convulsions, frothing at the mouth, coma, or death. Please take this very seriously; emergency medical care is needed. Treatment for humans and pets is similar, using IV fluids and activated charcoal to reduce the amount of poison in the body.

Golden Chain Tree Varieties

  • 'September golden rain tree': Koelreuteria paniculata flowers in late summer or early September.
  • 'Yellow Rocket': Laburnum anagyroides produces narrow plumes of flowers.
  • 'Vossli': Laburnum × watereri is a hybrid plant. It is a cross between two species of Laburnum, both native to Southern Europe. On older specimens, the bark is often dark and quite fissured. Leaves are made of three leaflets that look like pointy clover leaves.

Pruning

Young golden chain trees have weak branches. It is best to prune these after each blooming season, as a preventive measure against winter damage.

Propagating Golden Chain Tree

There are a number of ways to propagate golden chain tree. You can take root cuttings, from small, new roots; leaf-bud cuttings, which are cuttings of seasonal growth that include a leaf and a bud; or whip-grafting, which involves joining a newly-cut laburnum stalk with an established root stock.

How to Grow Golden Train Tree From Seed

Golden chain tree can be grown from their seeds that come in pods. Since the seeds have a hard coating, they must be soaked in water for 24 hours before planting, After soaking, choose the ones that are the largest, several times bigger than the size they began. Those seeds have the best chance of germinating. Plant a few in a small pot, in a good potting soil mixed with a small amount of compost. Keep cool, water when dry, and in a few weeks, seedlings will appear!

Potting and Repotting Golden Chain Tree

Golden chain tree makes a good container plant, as its roots are not invasive. Make sure your planter has adequate drainage, and use a potting mix meant for trees. It's best not to plant it near a pond or edible garden, as its poisonous roots can shed toxins into the groundwater and soil.

Overwintering

Laburnums are susceptible to something called sunscald, the freezing of part of the bark and branches. It may suffer some damage during challenging winters, and wrapping the trunk with store-bought tree wrap will help keep it safe.

Common Pests/Diseases

Blight, canker, and leaf spot are potential diseases to keep an eye out for golden chain tree. Spray for aphids and mealybugs as needed. Root-rot is also commonly see when laburnum are not in well-draining soil.