Few flowers can match the diversity and distribution of theRainbow Run, which encompasses several distinct groups, each with unique cultural needs. Although all irises share sword-like leaves and flowers with six spreading or drooping lobes, there are groups that grow from creeping rhizomes while others grow from bulbous structures; Some groups of irises are categorized as "bearded", some as "beardless", and still others as "crowned". Japanese,Dutch, AndSiberian irisare among those who fall into the beardless category. But the bearded iris (German rainbow) is arguably the most popular and among the easiest to grow. From the nursery onwards, the bearded iris is usually planted in spring and flowers in the first year. When planted from bare roots, it can be planted in fall or spring; Bare-rooted plants may not bloom profusely for the second year. These plants are poisonous to dogs and cats.
|plant type||Herbaceous, perennial|
|mature size||12-40 inches high, 1-2 feet wide|
|soil type||Average, well draining|
|flower color||Red, orange, yellow, blue, purple, brown, white, pink, many bicolors|
|hardiness zones||3–9 (USDA)|
|home territory||Southern Europe and the Mediterranean|
|toxicity||Toxic to dogs and cats|
Bearded Iris care
The most popular of the irises, bearded irises are easy to grow provided you plant them in a sunny spot with well-drained soil. A big difference for growing irises compared to other perennials is that they don't like mulch. Mulching (as well as deep planting) encourages thisRhizometo develop rot, so leave your soil bare. Space plants at least 12 inches apart to avoid the need for frequent division.
Although irises don't suffer from many problems, routine lifting and dividing is necessary to control iris boreworm and keep plants healthy and productive.
Irises need full sun to thrive. Irises in full shade produce fewer flowers and can suffer from an increase in disease.
Heavy clay soilsdo not do well for growing irises, but sandy or gritty soils are excellent. If your native soil is heavy, consider planting irisesraised bedsto help drainage. You can also improve your soil with plaster of paris or organic matter like compost to brighten the soil.
Although irises like moisture, they also need good drainage to avoid rot problems. Water them when the top 2 inches of soil feels dry. These plants have good drought tolerance.
temperature and humidity
Irises are notorious for their hardiness. They don't mind extreme temperatures as long as the ground allows excess rain or snowmelt to drain. Irises damaged by high winds or hail may be susceptible to iris beetle larvae.
Apply a low-nitrogen 6-10-10 fertilizer around your irises in spring. Too much nitrogen promotes leaf formation at the expense of flowers. Bone meal is also agood fertilizer.
Species of bearded iris
Within the broad category of the popular bearded iris group there are also subcategories: large bearded, medium bearded, short bearded, miniature bearded and border bearded. The main differentiator of these subcategories is their stature, although they also differ somewhat in flowering time. Read plant labels carefully so you understand what type of iris you are buying.
New named species of bearded iris are developed for commercial sale each year, and the ranking of the most popular irises, conducted annually by the American Iris Society, changes frequently. If you are looking for irises to plant,It's a good idea to look for those that have won well-known awards like thatDykes Medal. There are many dozens of fine irises to choose from; Here are some award winners that are widely shared:
- "Party Song"is a pink and lavender large bearded iris that grows to 37 inches.
- "Abiqua Cases"is a true blue large bearded iris that grows to 39 inches.
- "Again and again"is a yellow reblooming large bearded iris that grows to 36 inches.
- "American Classic"is a white with blue-purple irises, a large beard growing to 36 inches.
- "Beatnick"is a dwarf bearded iris that grows up to 14 inches. It has lilac flowers with white highlights.
- "Big Blue Eyes"is a dwarf bearded iris with white and violet flowers. It grows to 14 inches.
- "Dark Challenger"is a very dark purple iris that grows up to 39 inches.
- "Dornvogel"is a beautiful yellow iris that grows up to 37 inches.
- "Queen's Circle"has white flowers fringed with blue-lavender. This iris grows to 32 inches.
- "That's it folks"is a towering 40 inch yellow gold iris.
- "Jesses Lied"is a 35 inch purple and white iris.
Faded, withered flowers should be pinched off immediately. This can encourage additional blooms or even a rebloom later in the season.
Iris clumps should be dug up, divided and replanted every four or five years to weed out diseased roots and iris borer damage. This keeps iris plants vigorous and allows you to propagate new plants as well.
Grow bearded iris
Sharing irisesnot only brings more plants to your garden but also keeps your existing irises healthy and vigorous. That's how it's done:
- In late summer, dig up the rhizomes with a shovel and shake off any loose soil. Any remaining flower stalks can be removed at this point.
- Gently pull or cut the rhizome clumps into sections. Make sure each section has a leaf fan; You can clip the foliage at an angle, leaving 3 to 6 inches of leaves intact.
- Examine the root sections closely and use secateurs to trim away any soft, rotten parts. Make sure you cut back the roots behind any bored tunnels - you might even come across live worms that should be exterminated.
- Replant each root section, just covering the rhizome. Place roots at least 12 inches apart; They will quickly fill in the blanks. Water thoroughly after planting and then weekly until frost sets in. New leaf growth will likely begin in late summer and fall, and the plant will grow vigorously when it returns in spring.
Divide irises every three to five years—or more often if iris borers have infiltrated the plants.
How to grow bearded iris from seed
Propagation by seed is typically only practiced by nurseries when attempting to breed new cultivars through careful cross-pollination. But it's certainly possible to grow irises from the tiny seeds found in the green oval pods that remain after the flowers have faded. If you collect the seeds and plant them about 1/4 inch deep in the garden, they will often sprout and mature into flowering plants within three years.
Note, however, that most garden irises are hybrids and plants that reproduce from their seeds do not usually "come true". The iris plants that you propagate by collecting seeds can look very different from the mother plant.
Propagation is almost always done by dividing root clumps - a faster and more reliable method.
Repot bearded irises
Although not a common method, you can grow irises in pots that are at least 12 inches wide. Use a loose, soil-free potting mix, leaving the tops of the rhizomes exposed or just covered. Be careful not to overwater the plants.
In colder climates, you may need to move the containers to sheltered locations for the winter to ensure plant survival. Irises in containers may be requiredDivide and Transplantmore common than those that grow in the ground - about every two years or so.
Cutting back foliage fans to about 6 inches in fall keeps the garden looking tidy, reduces leaf surface area that could harbor fungal diseases, and removes caterpillar eggs. Destroy any leaves you remove and do not add them to the compost bin.
If plants show signs of rot or borer damage, the roots should be dug up and examined in early fall. Cut off any diseased or worm-damaged sections and replant the remaining root sections. Ideally, this should be done several weeks before the onset of freezing weather to allow the roots to re-establish before the frost.
Common pests and diseases
Theiris drillis the most serious insect pest of irises. In spring the caterpillars hatch and tunnel through the leaves until they reach the rhizome in summer. Feeding tunnels allow the rhizome to become infected with bacterial rot, making the damage worse. Remove any iris leaves after the frost to remove caterpillar eggs as well. Where rhizomes have been invaded by worms, dig them up, cut off soft, infested parts and replant the pieces. This is also a good time to propagate your irises by division.
Major disease problems include bacterial soft rot, crown rot fungus, and fungal leaf spot. Mottled leaves and flowers indicate the presence of mosaic viruses. Affected plant material should be removed and destroyed (not composted). Good hygiene is usually enough to control these diseases; Fungicides are not usually required.
How to get bearded irises to flower
When an iris does not bloom, it can usually be attributed to one of four reasons:
- The rhizomes are planted too deep. If you replant divisions, make sure that the crown of the rhizomes is just covered with soil.
- Plants get too little sun. Make sure the iris gets at least six hours of direct sunlight each day.
- Plants were overfed. Too much fertilizer will cause the iris to put energy into leaf growth at the expense of the flowers. Iris only needs a single feeding in spring.
- Plants are too full. If the root clumps become too dense, the flower will fall off radically. Dig up your irises every few years to divide and replant.
Common problems with bearded irises
Unique among spectacular flowering plants, irises are largely trouble free. But watch out for these issues:
Leaves turn yellow or brown, fall over
This is usually a sign of root rot caused by excessively wet soil. It can also be the result of extensive damage from iris borers. It's best to lift affected root clumps immediately to cut away any soft, rotting areas and transplant into porous and well-drained soil.
Flower stalks tip over
Some irises grow up to 40 inches and may require staking to support the huge blooms. Irises grown in shady conditions can become even more leggy, necessitating staking.
Leaves have yellow and brown spots
Spotted leaves are the result of bacterial or fungal infections. Bacterial leaf spot usually starts at the edges of the leaves and gradually grows larger. Agaric spots usually appear on the inner part of the leaves and do not enlarge. Affected plant parts should be removed and destroyed. Keep the soil around iris free of mulch and debris. Good garden hygiene usually controls leaf spot diseases. Severe fungal infections can be controlled with fungicides.
How can I use irises in a landscape?
Bearded iris is a mainstay of the sunny border garden. They show themselves best when allowed to naturalize in large clumps. In general, it's best to position irises behind other plants that will obscure the yellowing, fading foliage that follows flowering.(Video) Iris Fall Cleanup for Bearded Iris Plants - do this before Winter
What is the difference between bearded iris and Siberian iris?
Both types of iris are hardy in zones 3 through 9, and both types bloom in spring. But irises have the larger flowers, with the eponymous fluffy "beards" on the downward-facing fall leaves. Siberian irises have smaller flowers with no beards and usually flower slightly later than bearded irises. The foliage of the Siberian iris is grassy and remains attractive in the garden even after the flowering period. The Siberian iris is more shade tolerant and the tough fibrous root clumps do not need to be divided as frequently as the bearded iris.
What is the difference between bearded iris and gladioli?
As members ofirisesFamily, both irises andgladiolus flowershave strap-like foliage and large, showy flowers in a variety of colors. However, gladiolus is a tender perennial that grows from a bulb and is not hardy in zones colder than 7. Gladiolus flowers grow in clusters that are staggered along a single stem, making them valuablecut flowers.
How long does an iris live?
If the roots are removed and divided every three to five years, your iris will live on almost indefinitely.
How do I prune irises for display in a vase?
Cut off the stems when the flower buds are just beginning to open. Early morning cutting is best. Dip the trimmed ends in a bucket of lukewarm water and snip the stems up at about a 1-inch angle. Expose cut irises in a cool place, protected from direct sunlight and drafts. Withered flowers should be pinched off immediately. Check the water level every other day and refill the vase as needed.(Video) How to Divide and Plant Bearded Iris
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Dykes Medal. American Iris Society.(Video) Planting Iris In Pots | Container Gardening