Yellowwood (Cladrastis kentukea 'Sweetshade')

Overview

The Yellowwood, formally known as Cladrastis kentukea ‘Sweetshade’, stands out as a highly desirable specimen tree for the landscape. It earns its common name from the yellow dye found in the heartwood, but its primary appeal lies in its showy, intensely fragrant white flowers that appear late in the spring. This deciduous medium-sized tree develops a handsome, broad, rounded crown, providing excellent filtered shade.

Cladrastis kentukea ‘Sweetshade’ is valued for providing multi-season interest, progressing from stunning blooms to bright green foliage, and finally culminating in clear yellow fall color. Despite its beauty, it requires relatively low maintenance once properly established. Gardeners appreciate this tree for its adaptability to average soils and its ability to serve as a stately feature in residential settings or along avenues.

When selecting a location for your Yellowwood, remember that it prefers full sun for the best flowering potential and benefits from protection against severe winds. The cultivar ‘Sweetshade’ offers a reliable structure, making it an excellent choice for those seeking an elegant, medium-sized shade provider that offers significant ornamental payoff without excessive upkeep.

Fast Facts

• Plant Family: Fabaceae
• Plant Type: Tree
• Hardiness Zones: USDA Zones 4-8
• Size at Maturity:
  • Height: 35-45 ft
  • Spread: 40-50 ft
• Bloom Time: May to June
• Bloom Description: White
• Sun Exposure: Full sun
• Water Needs: Medium
• Maintenance Level: Low

How to Grow

For successful establishment, plant your Yellowwood in the early spring or fall. It thrives best when sited in average, medium-moisture, well-drained soils, requiring full sun exposure to maximize bloom production. While establishing, ensure consistent watering; afterward, Cladrastis kentukea ‘Sweetshade’ tolerates some periods of dry soil, making it slightly more adaptable than some other flowering trees.

Watering should remain consistent throughout the first two seasons to help develop a deep root system. Fertilization generally isn’t necessary unless the tree is showing signs of nutrient deficiency in poor soil conditions. A key cultural note for this species involves pruning—always conduct any necessary structural pruning during the summer months.

Avoid pruning Cladrastis kentukea ‘Sweetshade’ in late winter or early spring, as cuts made during this period are highly prone to significant sap bleeding. Furthermore, the bark can be susceptible to sun scald, particularly on young specimens; providing temporary protection or ensuring placement where it receives some afternoon relief, or planting it where it receives filtered light, can prevent bark damage. If site selection allows, choose a location sheltered from the strongest winds to protect its somewhat fragile branching structure.

Landscape Uses

The manageable mature size of Cladrastis kentukea ‘Sweetshade’, reaching up to 45 feet tall with an equal spread, makes it an excellent small tree for residential lawns where space might be limited compared to massive shade species. Its broad, rounded crown provides lovely, dappled shade perfect for siting near patios, terraces, or seating areas, allowing others to enjoy the fragrant spring display up close.

This flowering tree also functions well as a specimen planting to anchor a corner of the landscape or grouped on larger properties where its structure can be admired from multiple angles. Because the roots tend to grow deep rather than aggressively surface-feeding, gardeners often report that other plants can be more easily grown underneath the canopy, an advantage when designing layered garden beds. Consider grouping several Yellowwood trees together for a spectacular mass blooming effect every few years when it hits its peak bloom cycle.

Standout Features

Flower Qualities

• Showy
• Fragrant
• Good Cut

Fruit Qualities

• Showy

Noteworthy Characteristics

Cladrastis kentukea, commonly called American yellowwood, is a medium-sized, deciduous tree of the legume family that typically grows 30-50’ tall with upright branching and a broad, rounded crown. It is noted for its pinnately compound foliage, panicles of fragrant white spring flowers, autumn seed pods and yellow fall color. The species is native to the southeastern U.S. and the cultivar ‘Sweetshade’ maintains this lovely structure, growing 35-45’ tall with a refined, rounded crown that offers fantastic seasonal appeal.

Tolerances

No specific tolerances listed as bullet points in the provided data.

Potential Problems

The Yellowwood tree does have a few vulnerabilities gardeners should be aware of. Verticillium wilt is a potential fungal issue that can affect the tree’s health. As mentioned in the cultural notes, pruning at the wrong time (late winter/spring) causes excessive sap bleeding, which stresses the tree.

Protecting the bark from winter sun and rapid freeze/thaw cycles is important to prevent sun scald, especially on young specimens. Furthermore, due to its somewhat brittle branching structure inherent to Cladrastis kentukea, the tree is vulnerable to breakage during heavy winter snow/ice loads or severe storms. Finally, gardeners should expect that profuse blooming might only occur every two or three years, and late spring frosts can occasionally damage the developing flower buds.

Frequently Asked Questions

What hardiness zones is Yellowwood suitable for?

Cladrastis kentukea ‘Sweetshade’ is reliably hardy in USDA Zones 4 through 8.

How large does Cladrastis kentukea ‘Sweetshade’ grow?

When mature, this tree typically achieves a height between 35 to 45 feet and spreads outward 40 to 50 feet, forming a broad, rounded silhouette.

What sun exposure does Yellowwood need?

For optimal performance and the best display of flowers, this tree requires full sun exposure.

When does Yellowwood bloom?

The Yellowwood produces its signature white, fragrant flowers reliably in late spring, generally from May well into June.

Conclusion

The Yellowwood (Cladrastis kentukea ‘Sweetshade’) offers exceptional ornamental value through its fragrant white flower panicles and clear yellow autumn foliage, all wrapped in a low-maintenance package. Planning to site your Yellowwood away from high winds and using the correct summer pruning schedule will ensure many years of enjoyment from this beautiful specimen tree. Always check your USDA zone compatibility before planting.

Companion Planting

Due to the Yellowwood’s preference for full sun and medium moisture, pair it with understory shrubs or perennials that share similar cultural requirements. Consider pairing it with plants that tolerate the filtered light it casts once leafed out, such as Hostas or certain shade-tolerant ferns, though remember its deep root system requires competition-tolerant companions. In spring, consider planting early-blooming bulbs like Daffodils or Creeping Phlox around the base before the Cladrastis kentukea ‘Sweetshade’ canopy fully develops, as these will finish flowering before the summer heat sets in.

Seasonal Care Calendar

Spring is the crucial time for monitoring Cladrastis kentukea ‘Sweetshade’. Watch for late frosts that could damage the emerging flower buds; if frost occurs, the bloom may be reduced that year. Once the threat of frost has passed, inspect the bark for any signs of winter damage and apply protection if needed. Summer is dedicated to pruning; if structural work is required, summer is the only safe time to make cuts to prevent severe bleeding. Fall is when the tree showcases its handsome yellow foliage before dropping its leaves. In winter, protect young trunks from animals and heavy ice buildup to prevent branch breakage.