Landscape and Garden Plant Finder
Sulphur Queen Flag Iris
Iris pseudacorus 'Sulphur Queen'
Sulphur Queen Flag Iris flowers
(Photo courtesy of NetPS Plant Finder)
Plant Height: 3 feet
Flower Height: 4 feet
Spacing: 18 inches
Hardiness Zone: 4
Other Names: Yellow Flag, Yellow Water Iris
Bright sulphur-yellow flowers emerge from lush, sword-like foliage; perfect for water gardens as they require consistent moisture; hardy and easy to grow; cut back in the fall to reduce pests
Sulphur Queen Flag Iris has masses of beautiful lemon yellow flag-like flowers with yellow falls at the ends of the stems in mid spring, which are most effective when planted in groupings. The flowers are excellent for cutting. Its sword-like leaves remain green in colour throughout the season. The fruit is not ornamentally significant.
Sulphur Queen Flag Iris is an herbaceous perennial with tall flower stalks held atop a low mound of foliage. Its medium texture blends into the garden, but can always be balanced by a couple of finer or coarser plants for an effective composition.
This plant will require occasional maintenance and upkeep, and should be cut back in late fall in preparation for winter. Deer don't particularly care for this plant and will usually leave it alone in favor of tastier treats. Gardeners should be aware of the following characteristic(s) that may warrant special consideration;
Sulphur Queen Flag Iris is recommended for the following landscape applications;
- Mass Planting
- General Garden Use
- Bog Gardens
Planting & Growing
Sulphur Queen Flag Iris will grow to be about 3 feet tall at maturity extending to 4 feet tall with the flowers, with a spread of 24 inches. When grown in masses or used as a bedding plant, individual plants should be spaced approximately 18 inches apart. The flower stalks can be weak and so it may require staking in exposed sites or excessively rich soils. It grows at a medium rate, and under ideal conditions can be expected to live for approximately 10 years.
This plant does best in full sun to partial shade. It is quite adaptable, prefering to grow in average to wet conditions, and will even tolerate some standing water. It is not particular as to soil type or pH. It is somewhat tolerant of urban pollution. This is a selected variety of a species not originally from North America. It can be propagated by division; however, as a cultivated variety, be aware that it may be subject to certain restrictions or prohibitions on propagation.