Plant Calculator
Enter the approximate length and width of the area you will be planting and click 'Calculate' to determine how many Galphimia glauca 'Rain of Gold' you will need.
*Correct and successful spacing is complex and depends on project conditions.
Galphimia glauca 'Rain of Gold'
Golden Thryallis
- Long bloom season
- Drought & deer tolerant
- Sun-loving shrub
- Category: Seasonal, Tropical, and Perennial Color
- Hardiness Zone: 8b
- Height: 3-6 ft
- Spread: 3-6 ft
- Spacing: 3-5 ft
- Bloom Color: Yellow
Golden Thryallis is a semi-evergreen to deciduous shrub prized for its bright yellow, star-shaped flowers that appear from late spring through fall. Though not a Texas native, it is well-adapted to Central and South Texas thanks to its heat tolerance, drought resistance, and long bloom season. The fine-textured foliage and upright growth habit make it an excellent choice for foundation plantings, low hedges, or accent borders in full sun landscapes.
It prefers well-drained soils and grows best in full sun, where it will flower most profusely. Golden Thryallis tolerates both acidic and alkaline soils, as long as they are well draining. Once established, it is highly drought-tolerant and deer-resistant, and rarely troubled by pests or disease. It typically reaches 3 to 6 feet tall and wide, depending on climate and pruning. When planting in groups, space plants 3 to 5 feet apart.
In USDA Zones 8b–11, it is root hardy and may die back in hard freezes but will resprout in spring. In colder parts of Central to north Texas, it's often treated as a deciduous perennial. Prune lightly in early spring to shape and remove freeze damage. Mulching at the base before a hard freeze can help protect the crown.