Finding a hoard of aphids attacking the leaves and blooms of your prized iris plants is certainly dismaying These sap-sucking insects can quickly damage and deform iris foliage and flowers when infestations get out of control
Luckily, there are several effective organic and chemical treatment options for banishing aphids from iris for good. With the right control methods, you can get rid of aphids and keep your iris garden healthy and thriving.
Identifying Aphids on Iris
The first step is confirming that aphids are indeed the culprits damaging your irises. Aphids are tiny pear-shaped bugs less than 1/4 inch long. Colors range from yellow and green to pink, black, white or mottled. They tend to cluster in large groups on tender new growth, buds, and the undersides of leaves.
Signs of an aphid infestation on iris include:
- Clusters of small bugs on leaves and blooms
- Curling, wilting, or distorted foliage
- Sticky residue on leaves (called honeydew)
- Sooty mold fungus growing on honeydew
- Damage to opening buds and flowers
Aphids pierce plant tissue and suck out fluids, causing the foliage to distort and wilt. Their honeydew secretions also promote mold growth. Left untreated, heavy aphid populations can even kill iris plants.
Organic Aphid Control for Iris
Organic aphid treatments are ideal for gently eliminating aphids while protecting the rest of your garden, Here are some effective organic options
Insecticidal Soap
Insecticidal soap sprays suffocate soft-bodied insects like aphids on contact while being safe for plants when used as directed. Coat all surfaces of the iris foliage, including the undersides of leaves. Reapply every 5-7 days until aphids are gone.
Neem Oil
Derived from the neem tree, this non-toxic oil kills aphids and other insects by disrupting their hormones. Neem oil is also effective against powdery mildew. Follow label directions and reapply weekly.
Water Sprays
Strong blasts of water can physically knock aphids off plants. Focus on the undersides of leaves and new growth. Be careful not to damage tender iris blooms. Repeat daily until aphids are under control.
Diatomaceous Earth
This powder made from crushed fossils cuts into aphids’ bodies, causing dehydration and death. Avoid breathing in the dust by wearing a mask. Reapply after rain or watering. Be sure to get food-grade diatomaceous earth specifically made for gardens.
Horticultural Oils
These lightweight oils smother aphids on contact by coating and suffocating them. Treat irises according to product labels in early morning or evening. Oils also deter additional pests.
Ladybugs
Natural aphid predators, ladybugs and their larvae will feast on large numbers of aphids daily. You can buy live ladybugs to release onto infected plants. They will likely disperse to other areas of your yard once the aphids are under control.
Chemical Aphid Treatments
For severe infestations, you may need the quicker knockdown of chemical insecticides:
Insecticidal Soap Concentrates
More potent than natural soaps, insecticidal soap concentrates contain added chemical ingredients like potassium salts of fatty acids. Treat iris every 5-7 days as needed.
Pyrethrins
Derived from chrysanthemum flowers, pyrethrins attack aphids’ nervous systems on contact. These chemicals break down quickly to limit environmental persistence. Reapply every 7-10 days.
Neonicotinoids
Systemic insecticides like imidacloprid are absorbed into plant tissue and cause paralysis in aphids who ingest it. This provides longer control. However, neonicotinoids can be harmful to bees and other beneficials. Use judiciously.
Horticultural Oils
Lightweight refined petroleum oils smother insects for longer-lasting control than organic oils. Follow all safety and application guidelines carefully when using, as oils can damage plants if overapplied.
No matter which control method you choose, always follow the product instructions carefully to avoid harming iris or other pollinators. Combine treatments with frequent garden cleanup and smart watering and fertilization practices to make conditions less favorable for future aphid infestations.
Preventing Aphids on Iris
Prevention is the best medicine when it comes to avoiding aphid problems on precious iris plants in the future:
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Remove spent foliage and blooms promptly after the growing season to eliminate places where aphid eggs overwinter.
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Wash aphids off plants with a strong spray of water early in the growing season before populations explode.
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Apply row covers over iris in early spring to form a physical barrier against aphids.
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Use reflective mulches like aluminum foil around iris plants to confuse and deter aphids from landing and feeding.
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Interplant iris with aromatic herbs like garlic, chives, and alliums or pungent flowers like lavender and marigolds. The strong scents can help repel aphids.
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Use preventative horticultural oils and neem oil early in the season.
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Release predator insects like ladybugs, lacewing larvae, and syrphid flies to feed on aphids.
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Fertilize iris carefully to avoid excessive tender growth that attracts more pests.
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Prune overcrowded iris plants to improve air circulation and cut down on humidity that benefits aphids.
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Monitor for pest problems frequently and take quick action at the first signs of insects like honeydew or curling leaves.
Be Vigilant Against Aphids
Left uncontrolled, hordes of aphids can spell disaster for your carefully cultivated irises. But with close monitoring and the right organic treatments or judicious use of insecticides, you can knock out an infestation before major damage occurs. Combining control methods with prevention will help ensure your iris garden stays lush and beautiful, free of these destructive sap-feeding pests.
Preventing Aphids on Irises
Weed control around and in the garden is the best way to prevent aphids from invading your irises. Bindweed, pigweed, and lambs quarters are common host plants for green peach aphids in particular. Encourage natural predators such as lady beetles, lacewings, and syrphid flies to inhabit your garden. Planting pollinator-attractant plants and not using toxic pesticides are good first steps to encouraging a healthy garden biome. Remember that predatory insects need food to survive. If you get rid of all the aphids, the good bugs might leave too, looking for another food source. A balanced ecosystem helps keep both the predators and prey in check. Proper air circulation between plants keeps them healthy and discourages aphids from attacking. Keep supplemental fertilizing to a minimum. Overuse of nitrogen on plants encourages rapid foliage growth that is more susceptible to aphid attack.
Earwigs are one of the garden pests that gardeners can have mixed feelings about. These hungry chewing bugs will remove all the petals from a flower in one night. They also eat a lot of other bad bugs, like aphids, mites, fleas, and the eggs of many other pest bugs. Earwigs are pretty big and reddish brown. They like to hide during the day in cool, damp, and dark places. At night, they emerge ready to feed on mainly the flowers and flower stems of iris. Damage can be seen when petals have holes in the middle or ragged edges, or when whole flower buds are eaten away.
Preventing Gastropods on Irises
Preventing slugs and snails in the garden is an ongoing crusade. In some gardening zones, they are part of the local native population and will never fully be eradicated. Larger than that, slugs break down organic matter very well and are an important part of the soil web ring. Ensure that any weedy parts of your garden stay clean and open to the sun. Things like pots and hoses should be kept in a dry place or neatly stacked when not in use. Use iron phosphate slug baits only around plants that need protection. Do not spread it in large areas in hopes of killing all gastropods in your yard.
Aphids are common pests for most landscape plants. The sap-sucking pests often attack fresh new growth on plants that are compromised in some way. The green peach aphids, Myzus persicae, are the ones that are most attracted to irises. They are also known to spread mosaic viruses to irises. Green peach aphids feed on the plant’s sap from the leaves and flower buds, which bends and messes up the plant’s growth. If left uncontrolled, aphids will begin to excrete a sticky substance that is known as honeydew. This sap builds up on the plant’s surface and drips to the ground or other surfaces nearby. Ants are drawn to honeydew and will cover a plant while they try to get honeydew to take back to their nest.
How To Get Rid of Iris Pests | Iris Care | Garden Checkup
FAQ
Does soapy water kill aphids?
Does vinegar kill aphids?
How do you get rid of aphids on iris plants?
Alternatively, you can use an insecticidal soap or neem oil spray to kill the aphids. Remember to thoroughly coat both sides of the leaves for better efficacy. Iris borers are caterpillar-like larvae that tunnel into the rhizomes of iris plants.
How do you get rid of thrips on iris plants?
Applying an appropriate insecticide to the soil around the plants can also help prevent future infestations. Thrips are tiny, slender insects that feed on the leaves and flowers of iris plants. They cause damage by piercing plant cells and sucking out the contents, resulting in silvery streaks or speckles on the leaves and distorted flower buds.
What are the most common iris plant pests?
In this article, we will discuss some of the most common iris plant pests, along with their identification and treatment methods. Aphids are tiny, soft-bodied insects that feed on the sap of plants. They are commonly found on the buds, leaves, and stems of iris plants.
Do aphids eat Iris?
Aphids suck the sap out of plants and can transfer diseases. This may cause your iris to become deformed or die. The first—and often best—option to get rid of aphids is to just leave them alone. Birds love aphids. Also aphids lure in ladybugs, who along with their larvae, can eat several hundred each day.
