Silk Tree 'Ernest Wilson' (Albizia julibrissin) - The Silk Tree with "Extra Winter Hardiness"

A touch of the tropics that endures even in our latitudes: The Albizia julibrissin 'Ernest Wilson' is a special selection of the Persian Silk Tree (also known as Mimosa Tree). It combines the breathtaking, exotic beauty of the species with genetically improved and significantly enhanced winter hardiness. This cultivar owes its name to the famous plant hunter Ernest Henry Wilson, who discovered it in the climatically harsher regions of Korea in the early 20th century.

Scope of delivery: One young plant per 7cm pot (approx. 5cm)

Botanical Highlights in Detail

Growth and picturesque silhouette

'Ernest Wilson' grows as a large shrub or small tree, typically reaching a height of 4 to 6 meters with a similar width. Its crown shape is particularly picturesque: it naturally forms a broad, flat umbrella-shaped crown, providing light, shimmering shade. The growth is often multi-stemmed and elegantly spreading, making it the perfect solitary plant for terraces or Mediterranean garden areas.

The delicate foliage & the fascinating "sleep movement"

The bipinnate leaves resemble fern fronds or mimosas, lending the tree an incredible lightness. A fascinating phenomenon is the so-called sleep movement (nyctinasty): In darkness or rain, the countless small leaflets fold together in pairs, as if the plant is "going to sleep." The next morning, they open again in the sunlight.

Spectacular flower powder puffs

In mid-summer (July to August), the crown transforms into a sea of blossoms. The flowers consist mainly of long, silky stamens that resemble pink powder puffs with a white base. They have a delicate fragrance and are a magnet for bees, bumblebees, and butterflies.

The Secret to Success: Location, Hardiness, and Proper Young Plant Care

The perfect location

For 'Ernest Wilson' to develop its full splendor and winter hardiness, warmth is essential.

• Light & Warmth: Full sun, warm, and sheltered from wind is a must. A south-facing wall or a sheltered courtyard are ideal. The tree needs summer heat to allow the wood to ripen well by autumn.

• Soil: The soil must be excellently drained. Sandy-gravelly, rather lean soils are ideal. Heavy, wet clay soils and waterlogging (especially in winter) inevitably lead to frost damage or root rot.

Winter Protection in Practice: The Safe Way for Young Plants

Here lies the crucial difference between theory and practice. While 'Ernest Wilson' is considered the hardiest variety, established plants can tolerate temperatures down to approx. -18°C (Zone 7a). However: This does not apply to young plants. In the first two to three years, the wood is still soft and the bark thin.

Therefore, the golden rule applies: Play it safe and bring young plants indoors in winter!

Here's how to safely get your Silk Tree through its critical juvenile phase:

1. Container Cultivation: Keep the Silk Tree in a sufficiently large container for the first few years. This makes overwintering straightforward.

2. The Perfect Winter Home: Since the tree sheds its leaves in autumn, it enters a deep dormant phase. It needs no light in its winter quarters. You can overwinter the young plant perfectly in a cool, dark, and frost-free room such as an unheated garage, a cool cellar, or a shed. The temperature should ideally be between 5°C and 10°C, but must not freeze permanently.

3. Winter Care: During this dormant phase, the plant requires almost no attention. Keep the soil only minimally moist so that the root ball never becomes completely bone-dry. Do not fertilize.

The Way Outdoors and into the Open Ground

• Spring: As soon as severe, prolonged frosts are no longer a threat (approx. from April/May), the tree can be moved outdoors again. Initially, acclimatize it to the sun slowly in a semi-shady spot to avoid sunburn on the young leaves.

• Planting Out: Only when the trunk is significantly thicker and the wood is hard (after approx. 3 years), should the tree be permanently planted out in the open ground. Be sure to choose spring for this. This gives it the entire summer to establish a deep root system before spending its first winter in the garden (which you then protect with a thick layer of leaves over the root area).

Garden Use

The Albizia julibrissin 'Ernest Wilson' is a classic solitary plant that needs space to unfold its umbrella-shaped crown. It is the ideal shade provider for seating areas and fits perfectly into Mediterranean or exotic gardens. Due to its light shade, it can be underplanted with sun-loving, drought-tolerant perennials (e.g., lavender, sage) or grasses.