Aphids can attack any part of the plant, however they often suck sap from tender new plant growth, tips, flowers, etc. They often appear in small, rapidly reproducing colonies and are normally hidden from plain view, i.e. under the leaves. They are typically green, but can also be black or grey.
Chewing Damage
Beetles, caterpillars, earwigs, or slugs may be to blame if you notice holes or ragged portions of leaves missing and the damage has been happening gradually with a little feeding each night. Look for any remnants of these four to help you identify between them.
Caterpillars deposit their waste under the leaves or close to the damage. Droppings like tiny “pellets.” Certain caterpillars produce webbing. Damage can range from a few small holes in the leaves to the elimination of substantial amounts of the leaf. Cutworm caterpillars consume stems and leaves at night. Look for the curled-up caterpillars among plant stems close below the soil’s surface throughout the day.
Beetles frequently evade detection by falling to the ground and are less likely to leave droppings. As you search for them, they fall in reaction to the shifting of the leaves. Keep a close eye out for signals like egg clusters and small larvae under the leaves. Look for information on the plant that is being chewed to find out what insect pests are frequently linked with it. Caterpillars and beetles of many different varieties and sizes can be found in gardens.
The European earwig, which is common in New England gardens, can harm fragile fruit, corn silk, and young vegetables. The leaves of several varieties of vegetable plants will have numerous holes chewed in them. Older leaves typically have bitten edges, but younger leaves may have holes all over the leaf. Earwigs frequently gnaw on leaves that appear ragged.
As they feed, slugs exude a layer of slime that dries into a glossy trail. The slime aids in preventing their bodies from drying up, and it frequently leaves a deposit where the slug has crawled.
Look for pests at dusk or at night using a flashlight to conduct further research. Numerous earwigs, slugs, and beetles, in particular, feed at night and conceal during the day. In home vegetable gardens, handpicking caterpillars, beetles, and slugs and dumping them into soapy water can be helpful. Use shallow cans baited with fish oil or a dab of bacon grease in vegetable oil to catch earwigs.
Damage Caused by Piercing-sucking Insects
Look closely for tiny, soft-bodied insects in groups along the stems or under the foliage of plants with wilted, drooping leaves or small yellow patches. Squash bugs, whiteflies, and aphids all have mouthparts that resemble miniature straws. They take in nourishing plant liquids by sticking their mouthparts into a leaf or stem. This procedure leaves behind yellow flecks or patches. Whiteflies and aphids don’t get much bigger than 1/8 in length. Seek out a sticky substance known as “honeydew” on plants beneath or nearby where they feed. This residue frequently turns sooty from mold.
Squash bugs hatch from clusters of bronze-colored eggs that are typically placed on the underside of squash leaves. At first just about 1/8 long, grey, and soft, they develop into approximately 3/4-sized, brown, hard-shelled adults. While squash bugs travel around on the plant, frequently under the leaves, aphids and whiteflies feed primarily in one location.
Leaf-mining, Root-feeding and Stem-feeding Damage
Leaf miners are visible as winding, tan-colored spots on the leaves of Swiss chard, beets, and spinach. These minuscule fly larvae burrow between the leaf’s surfaces and form the splotchy tracks known as “mines. If a mine is still active, you can remove the top layer and find the tiny white maggot. The adult fly lays its eggs on a leaf’s surface, and the eggs hatch into larvae that burrow into the leaf’s inner tissue to feed.
Do the cabbage seedlings you have wilt? The cabbage root maggot fly lays its eggs close to the host plant (or seed), and its larvae emerge from the soil and burrow into the roots or seeds. It is closely related to onion and seed corn maggot flies. Broccoli, cabbage, cauliflower, radishes, and other cabbage family members are among the plants that are impacted, along with onions, vine crops (cucumbers, squash, pumpkins, melons, and gourds), and corn, pea, and bean seeds. The adults resemble tiny houseflies in size. The harm is caused by the larvae, or maggots, as they feed and burrow. Damage can result in wilting, poor germination, unattractive radishes, and rotting onions.
When cucumber seedlings wilt, become yellow, and maybe die, they may have Erwinia tracheiphila, a bacterial wilt disease that is spread by cucumber beetles. Look for small, 1/4-long beetles with yellow and black stripes or black spots that are eating the tender leaves of vine crops (cucurbits). Massachusetts is home to both the striped and the spotted cucumber beetle. Their harm includes spreading the wilt illness and feasting on stems, leaves, and roots. Most at risk are seedlings with less than five leaves.
The leaves of squash plants may start to wilt when they start to bear fruit. Look for excrement, also known as feces, along the stem from the wilted leaf “Frass is the sawdust-like residue that the insect feasting inside the stem left behind. Make a lengthwise slit in the stem close to the frass and look inside to find the huge, cream-colored caterpillar. After removing the caterpillar, add several inches of soil to the damaged area of the stem to promote roots. On squash plants during the day, keep an eye out for the orange and black adult moth, which soars like a little hummingbird. The moth deposits minuscule, rust-colored eggs on leaves and along stems.
Management Options
After determining the source of the damage, think about how you will handle the situation. You can either let natural enemies control the insect population or manually wash or remove the pests off the plants, depending on the extent of the damage. To protect crops from insects like flies, beetles, butterflies, and moths that lay eggs for caterpillars, consider using lightweight row coverings. For vine crops and seedlings of plants in the cabbage family, row coverings used at planting time frequently offer the best protection.
Products derived from natural components that contain Bacillus thuringiensis (Bt), neem (azadarachtin), or spinosad can be used to control some insects and caterpillars in vegetable gardens. Neem, various oil products, and insecticidal soaps may work well as both pesticides and/or deterrents for soft-bodied insects. Insects in their early, immature stages are always more susceptible to treatment than those in their later stages. Choose a product that is labeled for both the insect and the crop after carefully reading the labels.
Dusk is a good time to treat for active pests if you choose to apply a pesticide for three reasons:
- Pollinators and helpful insects are less likely to be active.
- Organic insecticides’ active components deteriorate more slowly in the absence of sunshine.
- At dusk, the wind frequently slows down, reducing spray drift.
Why are my potted plants dying?
Many different kinds of caterpillars might be attracted to your plants. Their feeding can be distinguished by the uneven holes in the leaves. The constructions that some caterpillars develop on trees, like tent caterpillars, make them simple to spot. Pull the tents off of the tree and into a basin of soapy water using a stick, along with all the caterpillars that are inside. To kill them, keep them in there for a day. An pesticide can eliminate a wide variety of different caterpillar species that don’t inhabit buildings.
Sawflies chew partial-throughholes in the leaf, which makes it appear entire but transparent. Leaf miners tunnel across leaves in a twisted fashion. Use horticultural oil or insecticidal soap to treat either condition.
Small holes are pierced in leaves by sucking insects, who then extract the fluids. Aphids, squash bugs, and spider mites are typical sucking insects. Spray insecticide on your plants consistently since sucking insects can reproduce so quickly that a single dose is frequently insufficient. If your plant is robust enough, a vigorous hose blast can effectively knock them away.
Your plants’ leaves will also be devoured by slugs and snails. Usually, you may get rid of them by creating an uncomfortable environment for them, as by scattering crushed eggshells around your plants.
Who or what insects damage houseplants?
Let’s examine some of the most typical pests of indoor plants. Sprays of insecticidal soap or neem oil can be used to get rid of the majority of these pests. Bacillus thuringiensis (Bt)-containing products can assist with worm or caterpillar issues.
Aphids
Aphids, often called greenflies or blackflies, are typically seen on indoor plants, however they can also be pink or slate-blue in color. You can see how simple it is for an aphid colony to grow up as aphids are able to reproduce without fertilization and will begin doing so within a week of birth if the plant is kept in warm circumstances.
Aphids consume food by suckling plant sap. They are drawn to tender, new growth tips. They weaken the plant and carry viral infections from one plant to another when they consume. A fungus known as sooty mold is drawn to the sticky, delicious “honeydew” that aphids exude. On the honeydew, this develops into dark patches that can hinder the plant’s ability to adequately photosynthesize.
Caterpillars
Plants are harmed by caterpillars, which typically eat holes in the leaves. Since the larval stage is when they are feeding, they have enormous appetites and can quickly cause a lot of harm to one plant.
One frequent offender is the carnation tortrix moth. These tiny, greenish-yellow caterpillars are typically seen at the tops of stalks. While they feed, they will create webbing and pull the plant’s leaves together.
Mealy Bugs
Mealy bugs resemble woodlice and are typically seen grouped in the axils of leaves. They have white, waxy fuzz covering them. On cactus, they are a problem. They prefer to hang out towards the spines’ bases. Like aphids, mealy bugs are sap suckers that can swiftly weaken a plant by secreting honeydew and luring sooty mold.
Red Spider Mites
Red spider mites are seldom visible to the human eye, but a hand lens will enable you to view them. They consume the sap, and the yellow speckling of the leaves is the first sign of an infestation. There is typically very fine webbing covering the tips of shoots. On the webs, the mites can occasionally be seen moving back and forth. These mites prefer dry environments, and heat is ideal. As the mites spread, plants may suffer significant harm. The fact that they spend the winter in crevices and gaps close to the plants makes it simple for this issue to return year after year.
Scale
Typically, scale insects are not seen until they have become a stationary gray or brown, limpet-like “scale.” They are fastened to leaves’ undersides and stems. These eat sap as well. They also produce honeydew, therefore sooty mold is typically present in infestations of this kind. With a fingernail, you can sometimes peel these insects off.
Vine Weevil
It is unquestionably the larvae that are the issue with the vine weevil. These larvae consume the plant’s roots while they are living in the compost. The collapse of the shoots and foliage is typically the first indication of the presence of the vine weevil. These critters adore cyclamen and will consume substantial amounts of the tuber until it is unable to support the plant.
The adult weevils will bite notches off of the edges of leaves. They are more active at night. Since they are unable to fly, these pests spend their days in soil-level plant debris.
Whiteflies
The whitefly is a small, white, moth-like insect that can rise in clouds from severely afflicted plants. To attempt to control it might be really difficult. Although these bugs go through a variety of life stages, only the adult pest is vulnerable to insecticides.
The same as other pests, whiteflies feed on plant sap. As a result, honeydew and sooty mold are a problem. Whiteflies make plants appear less vigorous, yet they don’t actually badly harm the entire plant. By decreasing photosynthesis, the mold can cause greater harm.
How can indoor plant pests be avoided?
Pests that affect houseplants are a pain, and it seems like they appear much more frequently in the winter. This is due to the fact that our plants are weaker than they were at the height of summer, growing more slowly, and receiving less light.
Keeping your plants as healthy as you can is the best defense. Here are 9 suggestions for keeping pests away from indoor plants.
1) Avoid overwatering your indoor plants. For fungus gnats, moist soil that persists for a long time is the ideal habitat. These bothersome little insects, which are sometimes mistaken for fruit flies, won’t actually hurt your plants. However, they are unpleasant to look at and exceedingly distracting. Since their eggs and larvae cannot live in dry soil, you should wait to water your plants again until the earth is completely dry on top. Yellow sticky traps can also be used to catch as many adults as you can.
2) Check indoor plants frequently for pest activity. Winter months present a special insect risk for indoor plants, making caution even more crucial. In the winter, you might not need to water every plant once a week, but it’s still a good idea to pay close attention to your plants. Check in particular the areas where limbs meet the main stem and the undersides of leaves. Look for tiny spots on the leaves (various pests), fuzzy white lumps (mealybugs), spider webs (spider mites), or groups of small, firm bumps (scale). If you discover pest activity, you should quarantine the impacted plants right once and start treating the infestation right away. Look for wilting, mold or fungus forming on the soil, and leaves that are yellowing or have spots.
3) Place any fresh plants you bring home in quarantine to stop the spread of any pests. Okay, we get that occasionally you just can’t help but bring home a brand-new houseplant baby from the garden center. We have similar traits! Just remember to exercise caution when introducing new plants. Put them in quarantine for at least two weeks, ideally in a room without any other plants. Every few days, check them for pest activity.
4) Make sure there is adequate airflow for your indoor plants. Numerous bugs find stagnant air that is not moving to be a perfect habitat. In rooms with lots of plants, it’s a good idea to have a fan on to keep the air moving and help ward off bugs and mold.
5) Wash your plants every so often. A good spray down of all the leaves, tops and bottoms, stems, and the pot can help keep pests at bay. Giving your plants a shower with lukewarm water, whether in the sink or the shower itself, accomplishes two goals.
6) Clean and disinfect pots before adding fresh plants to them. When you are repotting, avoid moving plants into unclean containers. Make it a practice to either wash and bleach pots whenever you remove a plant from them or to make sure you have done so before you begin repotting your plant.
7) Increase the humidity, but only slightly. The majority of houseplants require between 40 and 60 percent humidity. The air in your home may become quite dry throughout the winter. If it does, think about placing a humidifier next to your indoor plants.
8) Remove any organic materials that is resting on top of the soil and clean up any fallen leaves. Pests thrive in conditions where damp leaves are lying on the ground.
9) The most crucial advice is to maintain the health of your plants, as robust and healthy plants are less likely to suffer from insect infestations. Look to see if your plants are:
- Having sufficient light
- During the growth season, receiving fertilizer
- in a saucepan of the proper size
- high-quality, draining potting soil was used for the planting
- Watered only when necessary.
Owning indoor plants nearly guarantees that you will experience a pest infestation at some point. However, you should be able to avoid pests on indoor plants if you try to keep your plants happy and healthy.