Stop Those Tiny Black Bugs from Ruining Your Beautiful Dahlias
As a dahlia enthusiast, I know how disheartening it can be to nurture these stunning flowers all season only to have them ravaged by tiny black bugs Dahlias are truly one of the jewels of the summer garden with their showy, brightly colored blooms that come in a dazzling range of sizes, forms and colors However, dahlias seem to be susceptible to some pesky insects that can quickly turn your prized plants into an unsightly mess.
The two main culprits that leave those annoying little black specks all over dahlias are aphids and thrips. If you notice clusters of tiny black dots on the leaves, stems or flowers of your dahlias, it’s likely one of these annoying pests. The good news is that with prompt action, you can get rid of them and save your dahlias.
What are Aphids?
Aphids are soft-bodied insects that feed by sucking sap from the stems and leaves of plants. The most common species that attack dahlias is the black bean aphid. These tiny pests are typically greenish-black in color. They tend to congregate in large groups on stems, leaves and flower buds.
Aphids secrete a clear, sticky substance known as honeydew. A black fungus called sooty mold will often grow on the honeydew. This black mold can quickly spread and coat leaves and flowers, making your plants look dreadful. Aphids also spread viral diseases. Left unchecked, aphids can weaken and even kill dahlia plants.
Getting Rid of Aphids
The best way to control aphids on dahlias is to take action as soon as you spot them. Here are some effective methods:
-Blast plants with water – Use a strong jet of water from your hose to knock aphids off plants. Focus on the undersides of leaves and stem joints where they tend to gather. Follow up with an insecticidal soap spray to kill any remaining aphids.
-Use neem oil – Neem oil is extracted from the seeds of the neem tree. It kills sucking insects like aphids on contact. It’s also a natural fungicide that helps prevent sooty mold.
-Apply insecticidal soap – Insecticidal soaps containing potassium salts of fatty acids quickly break down the protective coating on soft-bodied insects, causing them to dehydrate and die.
-Spray plants with a dilute solution of hydrogen peroxide – The bubbling action kills the aphids on contact. Dilute 1 part 3% hydrogen peroxide with 4 parts water and spray liberally on infested plants.
-Attract beneficial insects like ladybugs and lacewings that feed on aphids.
-Remove and destroy severely infested stems and leaves.
What are Thrips?
Thrips are tiny, slender insects that have fringed wings. They rasp plant tissues and suck the sap. This causes white or silvery scars on leaves, damaged flowers and stunted plant growth. Thrips also spread disease.
Thrips are especially fond of dahlia flowers. They are very small – just 1/25 of an inch long. You’ll need to inspect plants closely to spot them. You may see black dots of excrement on flowers and leaves before you actually see the insects themselves.
Controlling Thrips on Dahlias
Thrips are challenging to control because they reproduce rapidly, have multiple generations per year, and are mobile. Here are some tactics to reduce damage:
-Keep dahlia beds weed-free – weeds harbor thrips.
-Use reflective mulch like aluminum foil to deter thrips from plants.
-Hose down plants to dislodge thrips.
-Apply neem oil or insecticidal soap weekly to kill thrips and disrupt their lifecycle. Get good coverage on the undersides of leaves.
-Use sticky traps near plants to capture thrips.
-Spray plants with a dilute solution of hydrogen peroxide to kill thrips on contact.
-Apply beneficial nematodes to soil to kill thrips larvae.
-Remove and destroy badly damaged flowers and leaves.
By taking action as soon as you detect an infestation, you can get rid of these destructive little bugs and keep your dahlias looking their best. Be vigilant and don’t let aphids or thrips ruin your dahlia garden! With persistence and using organic control methods, you can protect your plants and enjoy their vibrant blooms all season long.
Black Bean Aphids and Control
You might not see black bean aphids (Aphis fabae) until they make a big group on the new stems and leaves of your dahlias. But they have been there for months. This generation’s eggs or females without wings spent the winter and spring on spindletrees, snowball bushes, or fake orange bushes. Then, a generation of females with wings moved to dahlias and other summer hosts.
Black bean aphids drink sap and then leave behind gooey, clear honeydew. This honeydew often attracts sooty mold fungus, which turns leaves black. The females can have five babies a day, and most of them are also pregnant. They can have more babies in a week. Even worse, the pests can transmit several viruses, including leaf-mottling dahlia mosaic and cucumber mosaic virus. More Like This.
If you see aphids on a plant, set your hose spray attachment to jet or strong spray and spray it until all the aphids are gone. Do this in the early morning so the leaves dry quickly and have less risk of fungal infection. Repeat daily until the aphids are gone. Use insecticidal soap to get rid of a lot of aphids. Follow the directions on the package and make sure to cover all of the infested areas.
What Are The Black Bugs on a Dahlia?
FAQ
How to get rid of tiny black bugs on dahlias?
How to treat mites on dahlias?
How do I get rid of little black bugs on my flowers?
What is the black stuff on my dahlias?
Do bugs eat dahlias?
Bugs Eating My Dahlias! Below are the most common insect pests affecting dahlia plants in the garden: Thrips – Slender pests with fringed wings, Thrips damage plants by puncturing the leaves and sucking out the juices. Although thrips rarely kill dahlias, they can affect the appearance by causing stippled leaves, leaf drop and stunted growth.
Are dahlias a pest?
Dahlias, with their stunning blooms and lush foliage, are a magnet for various garden pests. These beautiful plants, while resilient, can be susceptible to infestations that threaten their health and vitality. Common pests like aphids, spider mites, slugs, and earwigs are attracted to dahlias, drawn by their vibrant flowers and tender leaves.
Do thrips kill dahlias?
Thrips – Slender pests with fringed wings, Thrips damage plants by puncturing the leaves and sucking out the juices. Although thrips rarely kill dahlias, they can affect the appearance by causing stippled leaves, leaf drop and stunted growth. Pesticides aren’t usually helpful because the pests move from plant to plant so quickly.
How do you get rid of Dahlia insect pests?
Using nosema locustae is a safe way to get rid of these insects. Proper plant care is the best line of defense against dahlia insect pests, as healthy dahlia plants are more pest-resistant. Water properly and apply fertilizer carefully according to label directions.