| Bloom season | Mid-summer through frost |
| Mature height | 8–12 ft |
| Sun | Full sun for best bloom |
| Varieties covered | Diana, Minerva, Blushing Bride, Ardens |
Why Rose of Sharon Is Having a Moment
Rose of Sharon (Hibiscus syriacus, sold under the older name Althea) blooms in mid-to-late summer when most flowering shrubs have finished for the season — which is exactly why it's worth understanding the differences between varieties before you buy. We carry four tree-form Althea varieties, and each solves a slightly different design problem.
Diana: The Pure White Classic
Diana produces large, pure white single blooms and is one of the longest-blooming Althea varieties available, often flowering from early summer through frost. It's also notable for being sterile — unlike many older Rose of Sharon varieties, Diana won't self-seed aggressively around your yard, which is a common complaint with older cultivars.
Minerva: Color Contrast
Minerva features lavender-pink single blooms with a bold dark red eye at the center, giving significantly more visual contrast than the solid-white varieties. It's a strong choice if you want a Rose of Sharon that reads as a focal point rather than a soft backdrop shrub.
Blushing Bride: Double Blooms, Softer Look
Blushing Bride produces large, double soft-pink blooms — more petals per flower than the single-bloom varieties, giving a fuller, almost peony-like appearance. Double-bloom varieties tend to hold their shape a bit longer on the shrub before dropping, though they can be slightly less attractive to pollinators than single-bloom types, which have more accessible nectar.
Ardens: Bold Purple
Ardens offers double purple blooms, the deepest color of the four varieties. Like Blushing Bride, its double-flower form gives a showier, more layered appearance than the single-bloom whites.
Quick Comparison
| Variety | Bloom Type | Color | Best For |
|---|---|---|---|
| Diana | Single | Pure white | Longest bloom season, non-invasive |
| Minerva | Single | Lavender with red eye | High contrast, focal point |
| Blushing Bride | Double | Soft pink | Fuller, romantic look |
| Ardens | Double | Deep purple | Boldest color statement |
Care Basics That Apply to All Four
Rose of Sharon wants full sun for the best bloom count, though it tolerates partial shade with a lighter flower show. It's adaptable to a wide range of soil types and, once established, is fairly drought-tolerant — a genuinely low-maintenance flowering shrub compared to most summer-blooming alternatives.
Frequently Asked Questions
Does Rose of Sharon spread or self-seed?
Older varieties can self-seed aggressively. Diana specifically was bred to be sterile and won't spread this way.
How tall do tree-form Althea varieties get?
Most mature to 8–12 feet, though regular pruning can maintain a smaller size.
When does Rose of Sharon bloom?
Typically from mid-summer through the first frost.
