Where do irises grow best?
Irises will bloom best in full sun, meaning at least 6 to 8 hours of sunlight per day. They can tolerate as little as half a day of sun, but it's not ideal. Without enough light, they won't bloom well. Bearded irises must not be shaded out by other plants; many do best in a special bed on their own.
Most iris species (bearded, Siberian, Japanese, etc.) perform best when grown in partial to full sun. However, the crested iris (Iris cristata) prefers partial shade. A native of the eastern United States, crested iris produces 4- to 6-inch-long leaves from woody, spindle-shaped rhizomes.
Some types of irises can also handle partial shade. However other varieties—such as bearded irises—cannot. Irises cannot get too much sun but they can suffer in extreme heat. Be sure to plant irises somewhere with plenty of sun, but be sure to provide heat protection in late summer.
Iris Growing Tips
Follow these tips for the healthiest plants and best blooms: Plant them in a sunny spot in late summer. The plants need well-drained soil and at least six hours of sunlight per day. A full day of sun is even better to keep the rhizomes dry.
Late July through mid August is the best time to plant, move or divide iris. Iris is one of the most popular perennials in the garden and easy to grow.
Bearded iris multiply quickly and the number of fans can triple every year. Clumps that become too dense can start to decline in the middle, and should be dug and divided every 3-4 years.
Water: Once established, they are very drought tolerant but would prefer a deep soaking every so often. Constant moisture in warm humid areas will encourage crown rot. Light: Full sun with a minimum of 6 hours to bloom properly. Afternoon shade in hot areas will benefit bloom.
Such plants also spread by rhizomes, and irises are no exception. While some rhizomatous plants, like bamboo, spread rapidly and even invasively, the iris spreads fairly gradually—one of its main virtues for gardeners. But, as iris rhizomes spread, they become crowded.
Some gardeners prefer to treat them as annuals and plant fresh bulbs every fall but if the iris bulbs are happy in a sunny, well-drained spot, they will bloom for many years. Remove the blooms as they fade and the foliage will continue to grow through the summer, providing nutrition for next year's bloom.
Water generously after planting.
If conditions are dry, water every 7 to 10 days or as needed during the morning or evening. Assuming you planted your irises in the late summer or early fall, you may stop watering your plants as soon as the weather cools and it begins raining or snowing.
Should irises be deadheaded?
Iris Care: Deadheading
After your irises have bloomed, remove the dead blossoms. This prevents the plants from using up their energy in ripening the seed heads. If your irises stop producing blooms, they may have become overcrowded. Dig up the bulbs in early fall and separate them before replanting.
If your iris is overwatered, the leaves will turn yellow and then brown. This usually happens when people are watering their plants too much within a few days or weeks. Overwatering can cause sunburn of the roots, which will eventually kill the plant and make the leaves brown and fall off.

Performance Organics Blooms Plant Nutrition by Miracle-Gro – Best Overall Irises Fertilizer. This is one of the most fast-acting plant food for flowering plants since it starts showing results within the first week of application.
Your irises need more sun.
You'll be able to grow lush iris foliage in the shade, but don't expect too many flowers. In order to bloom, irises should be getting at least six to eight hours of full sunlight. In climates with extreme heat, they'll need some afternoon dappled shade to keep them from getting scorched.
Iris can be successfully grown in containers. A 6" to 8" pot will work for Dwarf Iris; a 12" pot will work for Tall Bearded Iris. Make sure your pot has good drainage. For soil, we recommend 45% fir bark, 20% pumice, and 35% peat moss.
After two to four years, the irises become crowded from new growth and can stop blooming.
Since the eggs overwinter on the foliage, it's critical that you cut back irises in the fall. Trim off the leaves all the way back to the rhizomes, and toss them in the trash or bury them. If you come across a soft, rotten rhizome, dig it out and throw it away.
But how deep do you plant iris bulbs exactly? Plant the bulbs in holes 4” deep and 2” - 4” apart; for larger groups, dig out a trench, position the bulbs, then replace the soil and water them well.
It blooms from May to June, producing intensely white standards overlaid with yellow, and yellow-edged white falls. Grow the plant in full sun and well-draining, medium-moist, humus-rich soil.
- Prune. Grab your best pruning shears, and cut back the spent flower stalks near the plant's base. ...
- Fertilize. Light fertilization in the summer bodes well for your iris plants' health. ...
- Weed.
Do squirrels like irises?
Siberian Iris – Siberian iris offers early season color and intricate, frilly flowers that squirrels will avoid.
Low-nitrogen fertilizers, such as 6-10-10, are ideal for the needs of Iris. When to apply fertilizer to Iris: 1) In the spring, about a month before bloom, apply a light application of fertilizer around the Iris clumps. This goes for dwarf iris, too, which bloom in March.
The reblooming bearded iris (Iris germanica) can bloom twice a year, in spring and autumn. The extended ornamental period makes it more popular and brings additional commercial values.
'You should begin cutting irises back after flowering and the blooms have all begun to fade. The remainder of the plant's foliage should be left until the first signs of frost, however.
After dividing my irises, I called on friends and family to donate for their beds, but my garage was still full of rhizomes. I have a few friends who want starters for future planting, so I have put them to rest until they could be relocated. If stored properly, the rhizomes will last a year.
Irises are susceptible to rot if they get too moist. That sandy, hot patch in your yard is perfect for their cultural needs. They can also take some shade if the soil is well drained. They will thrive in dry shade — under those pine trees, for instance.
Grown in the right spot, irises are easy to grow and long-lived. Most iris flowers bloom in summer, apart from the earliest bulbous types, such as Iris reticulata, which flower in early spring.
Because they're prone to dehydration and can withstand freezing temperatures, they're usually left in the ground for overwintering instead of being lifted.
As blooms die, cut them off. If you trim the leaves, do it in late fall or early winter, but leave them on as long as possible since rhizomes use them to produce food. Once you have trimmed the leaves back, leave the plant alone. If you live in a cold climate, cover the iris bed with mulch or straw for winter.
The flower stalks range in height from 8 to 40 inches, depending on the variety, and are hardy in zones 3 to 9. Cultivars are often divided into groups by height, ranging from dwarf bearded to tall bearded. Blooms come in a range of colors, and the plants have stiff, upright leaves. All make good cut flowers.
Do irises like coffee grounds?
As irises like having extra nitrogen, consider mixing in some of the following: Used coffee grounds. Shredded leaves. Used coffee filter.
These are actually semiaquatic, and although they can live in dry soil, they thrive in saturated, poorly drained conditions. Most will grow far larger in wet ground than in drier soil.
Leaf spot is a common disease of iris, especially rhizomatous species. It is caused by the fungus Didymellina macrospora. The first evidence of the disease is the appearance of small yellow-brown spots on leaves that are surrounded by a water-soaked border. The spots enlarge, turn brown and dry.
For a spring garden full of blooms, use these companion plants for iris: Columbine. Daffodil. Tulips.
Irises are beautiful flowers that are easy to care for in your garden, but they can be easy to forget about once summer ends. To keep your flowers in tip-top shape, get in the habit of trimming back your irises every fall so they grow back once warm weather arrives again.
Iris need to be thinned or divided before they become overcrowded, generally every 3-5 years. If Iris are allowed to become too crowded the bloom will suffer, some varieties may crowd others out and disease problems may be aggravated.
Use bamboo stakes to help keep your dahlias and iris upright. Carefully place the stake next to the plant making sure to avoid the underground tuberous roots and rhizomes. Loosely tie the plant to the stake using twine. Make a figure eight looping the twine around the stake and the other loop around the plant stem.
A. Flopping iris indicate it's time to divide the clump, especially if this has not been done within the past three years. Iris also will fall over if they are growing in too much shade or if they have been over-fertilized with a high-nitrogen mix that will spur foliar growth at the expense of flower development.
Epsom salt is only good for irises if they have a magnesium deficiency. 'Unless magnesium is deficient (shown by inter-veinal yellowing of older leaves) there is no need to add magnesium as Epsom salts.
With the right care, iris should last for 5 to 7 days. Upon arriving home, follow a few simple steps to get the most out of your blooms: When you get home, stand the wrapped flowers in water so they can get a good drink while you're getting the vase ready.
Is mulch good for iris?
Since the rhizome likes to be exposed to the sun, we do not use mulch. Mulch can also create moist conditions around the rhizome and not let enough air circulation around the plant, which can cause rotting. If the rhizome gets mushy, that is a condition called rot, which will kill the plant.
When you notice iris plants not flowering, the cause can stem from a variety of issues including weather, soil fertility, overcrowding, unhealthy rhizomes, insect or disease attack, planting depth, and even site conditions.
Most iris plants spread by means of underground stems called rhizomes. Rhizomes become too crowded over time, resulting in reduced flowering. By lifting and dividing the larger clumps, you can rejuvenate the old planting, as well as provide a source of new plants to expand your garden or share with friends.
Shade and overcrowding are the most common culprits when irises won't bloom. If your irises aren't in full sun, move them to a brighter spot. If that's not the problem, you many need to dig up and divide your plants. The best time to do this is 6 to 8 weeks after they've finished flowering (or should have flowered).
Irises will bloom best in full sun, meaning at least 6 to 8 hours of sunlight per day. They can tolerate as little as half a day of sun, but it's not ideal. Without enough light, they won't bloom well. Bearded irises must not be shaded out by other plants; many do best in a special bed on their own.
Distance Apart: Iris are generally planted 12 to 24 inches apart. Close planting gives an immediate effect but closely planted iris will need to be thinned often. Plants spaced further apart will need less frequent thinning.
Irises should be fertilized in early spring about 6 to 8 weeks before bloom, and again after the blooms are gone. Because phosphate is important, we recommend bone meal or super-phosphate and a light balanced fertilizer such as 10-10-10 or 6-10-10 depending on the amount of nitrogen in your soil.
Some gardeners prefer to treat them as annuals and plant fresh bulbs every fall but if the iris bulbs are happy in a sunny, well-drained spot, they will bloom for many years. Remove the blooms as they fade and the foliage will continue to grow through the summer, providing nutrition for next year's bloom.
They can also take some shade if the soil is well drained. They will thrive in dry shade — under those pine trees, for instance.
Where to plant irises. Border and Siberian irises love a sunny spot, although Siberian irises cultivars will tolerate some dappled shade. Both types of iris thrive in any well-drained soil, but Siberian irises tolerate a damp soil as well.
Should iris be deadheaded?
Iris Care: Deadheading
After your irises have bloomed, remove the dead blossoms. This prevents the plants from using up their energy in ripening the seed heads. If your irises stop producing blooms, they may have become overcrowded. Dig up the bulbs in early fall and separate them before replanting.
Such plants also spread by rhizomes, and irises are no exception. While some rhizomatous plants, like bamboo, spread rapidly and even invasively, the iris spreads fairly gradually—one of its main virtues for gardeners.
Iris can be successfully grown in containers. A 6" to 8" pot will work for Dwarf Iris; a 12" pot will work for Tall Bearded Iris. Make sure your pot has good drainage. For soil, we recommend 45% fir bark, 20% pumice, and 35% peat moss.
With the right care, iris should last for 5 to 7 days. Upon arriving home, follow a few simple steps to get the most out of your blooms: When you get home, stand the wrapped flowers in water so they can get a good drink while you're getting the vase ready.
After two to four years, the irises become crowded from new growth and can stop blooming. Dig up the clumps and divide them.
Mulching – whilst we don't advocate heavy mulching around irises all year round, we like to mulch our irises in the summer with some rice hulls. This conserves the moisture in the soil, and has usually dissipated into the soil by winter to allow for those cold snaps that irises seem to like.
Plant them in different places, with either other Tall plants (Alliums, Delphiniums, Lupins, Foxgloves, Phlox). Use them with other smaller plants in front (Columbines, Dianthus, Cranesbill, Violas, Tulips, Lavender (dwarf varieties), or a combination of the two.
Caring for a Growing Iris
If conditions are dry, water every 7 to 10 days or as needed during the morning or evening. Assuming you planted your irises in the late summer or early fall, you may stop watering your plants as soon as the weather cools and it begins raining or snowing.
An amendment of superphosphate, colloidal phosphate, or bone meal applied in early spring can help plants develop blooms. Another reason for iris plants not flowering is overcrowding. The rhizomes will increase over time and plants become too packed in their site.