Plant dwarf iris bulbs in the garden and look forward to beautiful flowers in early spring. Plus, learn how to grow dwarf irises indoors.
Dwarf Iris Flower Growing Guide
Published on Oct. 30, 2024
On This Page
Care Tips for Dwarf Iris Flowers
- Common name: Dwarf iris
- Scientific name: All dwarf irises are in the Iris genus
- Zones: 3 to 9
- Light needs: Full sun, but some varieties tolerate partial shade
- Preferred soil: Well-draining soil—bulbs do not like soggy feet
- Size: Depends on variety; most top out at 6 to 8 inches
- Attracts: Bees and butterflies
There are more than 300 species of irises and they come in almost as many colors and varieties. Dwarf irises, like miniature irises and bearded irises, are a type of iris, so there isn’t one single dwarf iris species. The good news for gardeners is that with so many different types of dwarf irises, there’s probably one that will readily grow in your garden or backyard.
Are Dwarf Irises Perennials?
They are reliably perennial, so dwarf irises will come back every year as long as you choose a variety that suits your plant hardiness zone.
Allen Pyle, a horticulture expert and outreach specialist at the University of Wisconsin-Madison’s Division of Extension, says, “Hardiness varies among different types. For example, Iris cristata is hardy to Zone 3, Iris reticulata to Zone 5 and Iris verna to Zone 6.”
Do Dwarf Irises Spread?
Allen says, “When located in a suitable site in the garden and properly cared for, dwarf irises will multiply, whether rhizome types or bulbous types.”
When to Plant Dwarf Iris Bulbs
Most gardeners plant dwarf irises in their garden as bulbs and usually around the time the ground freezes (September through November), but Allen says they can be planted in late spring or summer as well. You can expect to see them bloom in very late winter and early spring, around the same time as crocuses and snowdrops.
Dwarf Iris Flowers and Foliage
Named after the Greek goddess of the rainbow, irises come in a wide range of colors. Dwarf irises are no exception. “They add vibrant color to the garden in early spring,” says Allen.
Dwarf irises share the same flower and foliage as their regular-sized counterparts just at a shorter stature. Irises typically have six petals: three that splay outwards and three that stand straight. Bearded irises have lower petals with a fanned, bushy shape and beardless irises don’t. Dwarf irises can be bearded or beardless, but beardless dwarf irises tend to be native to Asia.
Irises not blooming? Here’s what to do.
Growing Dwarf Irises Indoors
Like other early spring bulbs, dwarf irises can be forced to bloom indoors. Allen says that this is usually done with Iris reticulata, an easy-going, low-maintenance dwarf iris sometimes called netted iris, but it can work with other dwarf iris species, too.
“A period of cold temperature is required to induce the plants to flower,” he says. “This can be done by holding bulbs at temperatures between 35 and 40 degrees Fahrenheit for 10 to 14 weeks. An unheated garage, basement or shed work well during the chilling period.” During this time, keep the dwarf irises as loose bulbs or planted in pots.
“After chilling, dwarf irises will flower after a few weeks once brought into warmer conditions,” Allen says. “When blooming is complete, the forced iris plants can be saved to plant in the garden in spring or they can be disposed of.”
Garden Benefits of Dwarf Irises
Many varieties of dwarf irises have a sweet fragrance that attracts early-season pollinators like bees, butterflies and other native insects. They also deter deer. Allen says, “Dwarf irises are mildly poisonous, which is why they are resistant to deer damage.”
Dwarf irises are also generally tolerant of being planted near black walnut trees because they’re resistant to juglone.” (Juglone is a chemical that black walnut trees produce. This prevents other plants from growing beneath them.)
Pitfalls, Pests and Problems
When planting your dwarf iris bulbs, space them a few inches apart to avoid overcrowding. Make sure to plant them with the pointy end up. “Do not plant too deeply,” Allen adds. “Plant the rhizome or bulb with no more than 2 inches of soil above.” After planting, water well to help get the bulbs established.
If you’re worried about chipmunks and squirrels digging up the bulbs, you can try scent repellents like cayenne pepper, garlic or other natural repellents. Some gardeners also place wire mesh or chicken wire over their buried bulbs for protection, too.
About the Expert
Allen Pyle is a horticulture expert and outreach specialist at University of Wisconsin-Madison’s Division of Extension. He earned a bachelor of science in horticulture and a master of science in entomology, both from Michigan State University.
Sources
- U.S. Forest Service – Dwarf Iris
- North Carolina Cooperative Extension – Iris reticulata
- The American Iris Society – Iris Classifications
- National Garden Bureau – Bearded, Beardless or Dutch, there’s an Iris for you!
- Dwarf Iris Society
- Dutch Grown – Growing Guides: How to Grow Dwarf Iris Bulbs
- Nature Hills – The Different Types of Iris
- Longfield Gardens – All About Iris
