Bulb · Iridaceae
Reticulated Iris
Iris reticulata
Plant the little bulbs in fall and they open in icy blues and golds while winter still lingers.
Full sun
Every 7–14 days
USDA 5–9
4–6 in · 10–15 cm
Overview
Reticulated iris is one of the first flowers to break the late-winter gray. It grows from a small bulb wrapped in a netted coat, which is where the name comes from, and the blooms open in early spring before most of the garden has stirred. At just 4 to 6 inches tall, it slips easily into rock gardens, the front of a border, or a pot by the door.
The flowers carry the classic iris shape in miniature, in blues, purples, and pale icy shades, often lit by a streak of orange or gold on the falls. They come up alongside the thin, square leaves and last for a couple of weeks. A planting reads best in a generous drift, since the individual flowers are small.
Care
The short version: plant the bulbs in fall in full sun and sharp-draining soil, water through spring growth, then back off and let them bake dry while they're dormant in summer.
Light
Give this iris full sun for the strongest flowering, though it copes with partial shade. A bright open spot also helps the soil dry out in summer, which is exactly what the dormant bulbs want.
Water
Keep the soil moist through spring while the plant is growing and in bloom, then ease right off. Once the foliage fades and the bulb goes dormant for summer, let the ground stay fairly dry so it can set next year's buds. It shrugs off summer drought without complaint.
Soil
Sharp drainage matters more than anything else here. Plant in average, well-drained soil anywhere from a pH of 6.1 to 7.8, and avoid spots that stay soggy, since wet feet in summer rot the bulbs.
Temperature
The bulbs are tough, hardy from about -20°F to 100°F (-29°C to 38°C), so winter cold is no threat. They actually need that winter chill to flower well come spring.
Humidity
Ordinary outdoor air suits it fine, so there's no level to track. Dry summer soil matters far more to this plant than anything happening in the air.
Feeding
Work a low-nitrogen bulb fertilizer or bone meal into the soil at planting time in fall, with a second light feed in early spring. Go light on nitrogen, which pushes leaf at the expense of flower.
Pruning
Leave the foliage alone after the flowers fade and let it die back on its own, since those green leaves are recharging the bulb for next year. Cut away only the leaves that have fully withered.
Repotting
These bulbs like to be left undisturbed and only need lifting when the flowering drops off, usually every few years. Divide them after the foliage has died back, separating the crowded clumps and the small bulblets.
Size & spacing
Each plant stays small at 4 to 6 inches (10 to 15 cm) tall and 3 to 5 inches (8 to 12 cm) across. Set the bulbs about 3 to 4 inches (8 to 10 cm) apart so a planting reads as a tidy drift.
When to plant
This iris runs on a fall-to-spring clock. Set the bulbs in the ground in autumn so they root before the cold, then watch for flowers in March to early April while the rest of the garden is still waking up.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Plant bulbs in fall, 3-4 inches (8-10 cm) deep and 3-4 inches apart
- Harvest: March to early April (early spring)
Hardiness
USDA hardiness zones: 5–9
Temperature: down to -29°C
Troubleshooting
Most trouble with this iris shows up either underground at the bulb or on the soft spring leaves. Knowing the few things that go wrong makes them easy to head off. Match what you see below and act early.
Soft bulbs rotting from the base up
Wet soil during summer dormancy invites fusarium basal rot, which softens the base of the bulb and creeps upward in brown or pinkish streaks. Cut a suspect bulb open and you'll find the basal plate discolored and mushy. There's no saving an infected bulb, so throw it out, fix the drainage, and replant clean stock in a drier spot.
Fix:
- Discard affected bulbs
- Improve drainage and avoid summer irrigation
- Plant healthy bulbs in a new, well-drained site
Strong bloom the first spring, then nothing the next
This is a bulb going blind, and it's the most common letdown with this iris. The bulb naturally breaks into small offsets after flowering, and each of those bulblets needs several years to reach blooming size. Plant a little deeper at 3 to 4 inches, keep the soil dry through summer, and drop in a few fresh bulbs each fall to hold the display.
Fix:
- Replant supplemental bulbs annually for consistent bloom
- Plant bulbs deeper (3-4 inches) to discourage splitting
- Lift and grow on small bulblets in a nursery bed until they reach flowering size
Ragged holes chewed through the leaves and buds
Slugs and snails go after the soft new growth in spring, leaving torn holes and silvery slime trails behind. Scout after dark or lift any nearby debris to catch them in the act, then pick them off by hand. Clearing damp hiding spots near the planting and improving drainage keeps their numbers down.
Fix:
- Hand-pick slugs and snails
- Remove garden debris and mulch near plants
- Use iron-phosphate slug baits if needed
Toxicity
Treat the whole plant as off-limits to pets and people alike. Every part holds irritant compounds called irisin and terpenoids, and the bulb is the worst of all, so a chewed bulb brings on drooling, vomiting, and diarrhea. Wear gloves when you handle them and store spare bulbs where pets and children can't reach.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Mild
A cat that chews the bulbs or leaves usually drools and brings up its food, then turns dull and off its appetite. Loose stools often follow. The bulb is the part to watch, since that's where the irisin and terpenoids sit thickest.
Dogs Mild
Dogs that dig up and gnaw a bulb tend to drool heavily and vomit, with diarrhea and a flat, tired mood close behind. Diggers are the ones at risk, so stored and planted bulbs both belong out of reach.
Horses Mild
Grazing horses can salivate, scour, and lose their spark after eating any part of the plant. As with the smaller animals, the worst of the trouble comes from the bulb.
Rabbits Mild
The same irritant compounds upset a rabbit's gut, so keep the plant and its bulbs off the menu. A rabbit's digestion stalls easily, which makes any drooling or sloppy stools worth a quick call to the vet.
Livestock Mild
Cattle, goats, and sheep mostly leave the bitter foliage alone, but a hungry animal that nibbles it can drool and scour. Fence stock away from beds and never toss lifted bulbs onto pasture.
Birds Caution
There's little hard data on iris and birds, so treat it as a hazard rather than a safe nibble. Keep curious pet birds away from cut stems and stored bulbs to be safe.
People Caution
No part of this iris is food, and the bulb is the most toxic piece, so eating it brings stomach pain, nausea, and vomiting. Handling bulbs can also redden sensitive skin, so wear gloves and keep children from putting any part in their mouths.
Wear gloves when handling bulbs; sap can cause skin irritation/contact dermatitis in sensitive people. Store bulbs out of reach of pets.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
A handful of named selections cover most of what you'll find for sale, each leaning toward a different shade of blue. These are the ones worth knowing.
Harmony
Carries sky-blue to royal-blue flowers marked with a bright yellow-orange ridge down the falls.
Clairette
Pairs pale blue standards with darker blue falls that are flecked with white.
Gordon
Shows light blue flowers set off by a bold orange blotch on each fall.
Katharine Hodgkin
A much-loved hybrid in icy pale blue and soft yellow, laced all over with fine dark veining.
Companions
This iris looks best beside other early bulbs that flower at the same time and want the same sun and sharp drainage.
Plant near
Galanthus (snowdrops): Blooms at the same early-spring time and shares full sun, well-drained conditions for layered early color.
Crocus: Early-spring bulb with matching light and drainage needs; combines for naturalized rock-garden displays.
Chionodoxa (glory-of-the-snow): Early-blooming companion bulb that thrives in the same sunny, well-drained sites.
How to propagate
The easiest way to get more is to let the bulbs do the work, though you can also divide crowded clumps or take the slow route from seed.
Offsets & pupsEasy
After foliage dies back in late spring or early summer · Several years for bulblets to reach flowering size
This is how the plant multiplies on its own. Once the leaves have died back in late spring or early summer, lift the clump and you'll find the parent bulb has split into small offsets, more so where it was planted shallow. Separate those bulblets and replant them, but be patient, since each one can take several years to size up and bloom and most stay blind that first spring.
DivisionEasy
After foliage dies back, when flowering declines · 1-3 seasons
When an old clump grows crowded and flowering drops off, divide it. Wait until the leaves have withered, then lift the bulbs, pull them apart, and reset them at the right depth and spacing. They settle back in over the next one to three seasons.
SeedModerate
Sow ripe seed in fall; requires cold stratification · Several years to flowering
Growing from seed is the slow road. Sow ripe seed in fall and let the cold of winter break its dormancy, then settle in for a long wait, because seedlings need several years to reach blooming size.
Myths
Reticulated iris bulbs come back strong every spring on their own.
Most plantings put on a fine show the first year and then fade as the bulbs split into small bulblets that need several seasons to mature. Tucking in a few fresh bulbs each fall is what keeps the bloom dependable, rather than trusting the original planting to repeat itself.
A small ornamental iris is harmless to pets.
Size has nothing to do with it. Every iris is toxic to cats, dogs, and horses, and the bulb holds the most irritant compounds of all, bringing on drooling, vomiting, and diarrhea if an animal chews it.