HARDINESS: Zones 4 to 9
PREFERRED SOIL pH: Slightly alkaline to neutral
PREFERRED SOIL TYPE: Well-drained loam
PREFERRED LIGHT: Sun to filtered shade
ATTRIBUTES: Colorful flowers; green or variegated fan-shaped foliage; for beds, ground-cover, water gardens
SEASON OF INTEREST: Early summer to tall
FAVORITES: Re-blooming 'Immortality'; dwarf 'Baby Blessed'; Siberian iris for shade; nag iris for wet soil
QUIRKS: Irises grow poorly in hot, humid environments
GOOD NEIGHBORS: Lamb's ears, peonies, roses, clematis
WHERE IT GROWS BEST: Moist, well-drained soil; wet soil for Hag iris; sun, filtered shade
POTENTIAL PROBLEMS: Iris borer; fungal leaf diseases
RENEWING PLANTS: Lives years; divide clumps 3-5 years
CRITTER RESISTANCE: Excellent
SOURCE: Bedding plants, division
DIMENSIONS: 8 in-6 ft (20.3 cm-1.8 m) tall, 4-8 in (10.2-20.3 cm) wide
Iris in the Landscape
Irises are care-free survivors par excellence. You can find them lingering in abandoned gardens long after other plants have disappeared. Named for the ancient Greek goddess of the rainbow, irises are available in every color and combination of colors except true red. In early summer, they send up their famous fleur-de-lis blossoms. Each lingers for several days, then another opens to continue the show for 3-4 weeks. Out of flower, the fans of green or variegated leaves enhance beds. No pruning is necessary, and they're non-aggressive companions.
Tall Bearded Irises
The best known irises are the tall bearded types, named for the fuzzy, caterpillar-like "beard" at the center of each outer petal.or "fall." Traditional tall bearded irises send their flower spikes up 3 ft (1 m) or more. But beardeds now come in several variations, including miniature dwarfs, at 8 in (20.3 cm); medians up to 27 in (68.5 cm); and large-flowered "tetraploid" varieties. However, old hybrids tend to be tougher and are
often more fragrant. The wonderful bubble gum scent is something you'll never forget.
An important innovation is the development of re-blooming irises. White-blooming 'Immortality' and yellow-flowering, dwarf 'Baby Blessed' are superior examples.
Bearded irises are prone to two problems, fungal leaf spot and iris borers. Leaf spots, which are encouraged by damp, stagnant air, can be controlled by disposing of yellowing leaves. For prevention, divide and replant to promote good air circulation. To control borers, which tunnel in leaves and rhizomes, remove and dispose of infested tissue.
Elegant Siberians have flowers held on slender spikes above grasslike leaves. Colors include purple, blue, wine, pink, and yellow. There are also re-blooming varieties. Although tolerant of shade, Siberians thrive where they have sun, abundant moisture, and good drainage.Best of all, they are not prone to borers or leaf spots.
There are several durable and adaptable species. These include Louisiana irises, with showy 6 in (15.2 cm) flowers; miniature reticulata irises that sprout from bulbs early in spring, even in snow; and 6 ft (1.8 m) tall, water-loving flag iris (Iris pseudacorus).
Planting and Dividing Iris
Most irises grow from rhizomes that wander horizontally just below the soil's surface. Divide plants a month or so after blooming. Unearth die rhizomes and cut off 2-3 in (5.1-7.6 cm) long segments with a fan of leaves and some roots attached. Dry rhizomes in an airy, shaded place for several days. Replant them just below the soil surface. However, in damp locations leave the rhizomes slightly exposed. Siberian iris rhizomes should be soaked overnight if you can't transplant them immediately.