As a passionate petunia gardener, I know how disheartening it can be to walk outside and see your beautiful flowers covered in tiny little creepy crawlies. Those tiny green bugs munching away on the leaves and flowers are most likely aphids, one of the most common garden pests. While aphids typically don’t pose a huge threat to your petunias’ health, they can certainly gross you out and ruin your enjoyment of your garden. The good news is that with some knowledge and a proactive approach, you can wage battle against those tiny green invaders!
What Exactly Are Aphids?
The tiny green bugs that are eating petunias are probably the green peach aphid (Myzus persicae), which is one of more than 4,000 species in the family Aphididae. Aphids are soft-bodied, pear-shaped bugs that are about 1 to 3 mm long as adults. Nymphs look like adults, but they are smaller and don’t have wings. Aphids get food and water from stems and leaves by sucking on plant sap with their sharp, sucking mouthparts. This can make your petunias grow in strange ways, turn yellow, wilt, and even die if the infestation is bad enough. Black sooty mold can grow on a sticky substance that aphids make called honeydew. Yuck!.
How to Battle the Tiny Green Invaders
Luckily, there are several earth-friendly ways to combat aphids in your petunia patch without resorting to harsh chemical pesticides. Here are some tips and tricks I’ve learned from years of battling these tiny green bugs in my own garden:
-
Spray them with water. An intense stream of water can loosen aphids from plants. Aim the spray at the undersides of leaves and cracks where they like to hide.
-
Introduce beneficial insects: Ladybugs, lacewings, syrphid flies, and tiny parasitic wasps all feed on aphids naturally. You can buy them from garden stores or attract them by planting flowers they like.
-
Apply insecticidal soap Natural soaps disrupt aphids’ cell membranes and dehydrate them, Spray it directly on the bugs and repeat applications may be needed
-
Wear neem oil. The azadirachtin in neem oil keeps aphids from liking plants. It’s not a quick knockout but should discourage their feeding.
-
Use horticultural oil. These refined petroleum oils kill aphids right away by blocking their airways. Be sure to test first for leaf burn.
-
Consider pyrethrins: Derived from chrysanthemum flowers, pyrethrins attack aphids’ nervous systems. Use cautiously to limit harm to beneficial insects.
-
Remove weeds: Eliminate sowthistle, mustard, and other weeds that harbor aphids around your garden. This cuts off an important food source for them.
-
Check for ants: Ants “farm” aphids for their honeydew secretions. Stopping ants around your petunias can help reduce aphid populations.
-
Enlist helpful fungi: Fungal insecticides containing Beauveria bassiana infect aphids with deadly fungi while sparing most beneficials.
-
Tolerate some damage: Aphids rarely kill plants outright, so mild infestations can be tolerated. Focus control efforts on heavily infested areas.
Prevent Aphids from Returning
An ounce of prevention is worth a pound of cure when it comes to aphids. Here are some tips to keep your petunias unattractive to them next season:
-
Remove spent blooms and debris from the garden in fall to eliminate overwintering sites.
-
Cover susceptible plants with floating row cover early in spring before aphids arrive.
-
Use reflective mulches early in the season to confuse aphids when searching for plants.
-
Rotate petunias with unrelated plants from year to year to disrupt aphid cycles.
-
Select petunia varieties bred for aphid resistance when possible.
-
Water and fertilize appropriately to avoid stressed plants that attract aphids.
With vigilance and integrated pest management, you can win the battle against the tiny green bugs invading your petunias. Don’t let them ruin your enjoyment of these beautiful, long-blooming flowers. With a multi-pronged approach, your petunia patch will be back to its former glory in no time!
Preventing Rose Slug on Petunias
Preventing Rose Slugs is easily accomplished by maintaining good gardening hygiene from season to season. Use clean or fresh pots and potting mix every year. If there are no signs of Rose Slugs or sawflies, old potting mix can be used in the garden or broken down into plant food. Dispose of any affected foliage or plant material in the trash. Home compost piles rarely reach the high temperatures needed to kill off pests and diseases. Catching outbreaks early is critical in helping annual plants to recover. Daily or weekly inspections of plants go a long way in catching problems while they are small. Picking off one or two Rose Slugs will keep future generations from being laid.
Western Flower thrips are a pest that occurs more often in a protected setting of the greenhouse, but it can become a problem in the home garden where it acts as a vector, passing viruses from one plant to another. While the adults are easily recognizable by their slender bodies and long narrow leaves, the nymphs are very tiny and almost translucent. Every year, more than one generation is born, and the adults like to lay their eggs in leaves that are bent or damaged.
Nymphs may have caused damage that can be seen as spots on the leaves and big breaks in the color of the flowers. Damage is sometimes mistaken for spider mites, and only a microscope can tell who the real culprit is. Even though most of the visible damage is cosmetic and usually not serious, thrips can pass viruses that are harmful to plants quite easily.
Preventing Aphids on Petunias
Preventing an infestation of aphids is easily achieved by following a few cultural guidelines. The number one rule for growing healthy and strong plants is to make sure they are growing in their preferred location with the correct type of soil, pH, and nutrients. Petunias require full to part sun, good drainage, and a neutral soil pH. Ample air circulation is an important element in keeping aphids at bay. Plants growing too close together will eventually weaken in vigor and are easily attacked by pests and fungal diseases. Growing a happy plant starts with buying the healthiest plant available. Plants that are ‘rescued’ from the bargain bin will need a period of quarantine from other plants until it has regained strength with no sign of pests or disease.
The tobacco budworm, Heliothis virescens, is a caterpillar of the moth by the same name. They are common in the east and southwestern parts of the United States. In colder areas, such as the Mid-Atlantic states, the budworm overwinters in greenhouses and other protected sites. These caterpillars feed on all parts of ornamental plants and are most likely to disfigure flowers in the bud stage, or seed pods in the early green stage. Damaged flower buds will not open, while affected foliage will have a ragged appearance on the edges or whole sections eaten away in random patterns.
The caterpillars are yellow or light green with reddish-brown stripes on the sides of the body. The caterpillars are laid in the soil to overwinter by the moths and appear early in March or April. There are usually one or two generations a year. Newly planted Petunias may be affected by heavy feeding, although more mature plants usually recover well.
Q&A – How do I control small green bugs on my petunias?
FAQ
How to get rid of aphids on petunias?
To get rid of aphids on petunias, you can use a combination of methods, including manual removal, insecticidal soap, neem oil, and encouraging natural predators.
What are the green bugs on my petunias?
Many species of aphids feed on home garden plants; these insects range in color from pale green, pink, or black to red or yellow. Size is typically 1/16″ to 1/4″. Adult aphids are generally wingless, but winged adults will appear when overcrowded. Immature aphids (nymphs) closely resemble adults.
How to get rid of gnats on petunias?
Hydrogen Peroxide A peroxide solution apparently kills larvae and eggs on contact, effectively killing off all infant gnats and disrupting the lifecycle. You should be able to buy hydrogen peroxide from any high street pharmacy or online.
How to get rid of petunia mites?
If you detect spider mites, spray the plant with a strong stream of water early in the day to deter and knock insects off the stems. Spraying also rinses dust off plants. Prune away affected plant parts. Dispose of debris rather than adding it to the compost pile, which can harbor and spread the insects.