📄️ Anthracnose
Anthracnose is a name for several fungal diseases, not a single species. Depending on the plant, the cause may be a Colletotrichum species or another fungus…
📄️ Aphids
Aphids are small, soft-bodied insects that feed by piercing plants and drawing out sap. The group includes many species, commonly green, black, yellow, or…
📄️ Apple Scab
Apple scab is a fungal disease of apple trees caused by Venturia inaequalis. It also affects crabapples. The fungus survives winter mainly in fallen, infected…
📄️ Bacterial Leaf Spot
Bacterial leaf spot is a name for leaf diseases caused by several bacteria, commonly species of Xanthomonas or Pseudomonas. It affects many garden plants, but…
📄️ Bacterial Wilt
Bacterial wilt is a soilborne disease that blocks water movement through a plant’s vascular tissue. The name commonly refers to disease caused by bacteria in…
📄️ Birds
Birds are a class of animals, not a single pest species. In gardens, their effects depend on the species, season, and available food. Some eat ripe berries…
📄️ Black Spot
Black spot is a fungal disease of roses caused by Diplocarpon rosae. It develops most readily when leaves stay wet for several hours, particularly during…
📄️ Blossom End Rot
Blossom end rot is a noninfectious disorder of developing fruit, especially tomatoes and peppers, but also eggplants, squash, and melons. It occurs when the…
📄️ Bolting
Bolting is the premature switch from leafy or root growth to producing a flower stalk and seeds. It is a normal part of a plant’s life cycle, but it becomes a…
📄️ Borers
Borers are the larvae of various moths, beetles, flies, and other insects that feed inside plant tissue. “Borers” is a general name, not a single species…
📄️ Cabbage Worms
“Cabbage worms” commonly refers to the larvae of the cabbage white butterfly, Pieris rapae, also called the imported cabbageworm. These green caterpillars…
📄️ Canker
Canker is a general name for a localized area of dead bark and underlying tissue on a woody stem or branch, not a single disease with one scientific name…
📄️ Carrot Rust Fly
Carrot rust fly, also called carrot fly, is a small fly whose larvae feed inside the roots of carrots and other members of the carrot family, including…
📄️ Caterpillars
Caterpillars are the larval stage of butterflies and moths, not a single species. Many feed on garden plants, although some species are harmless or valued as…
📄️ Clubroot
Clubroot is a soilborne disease of cabbage-family plants, including cabbage, broccoli, cauliflower, kale, Brussels sprouts, radishes, and turnips. It is…
📄️ Codling Moth
Codling moth is a pest of apples, pears, quince, and walnuts. Its caterpillars feed inside developing fruit or nuts, making tunnels and leaving brown, crumbly…
📄️ Colorado Potato Beetle
The Colorado potato beetle is a leaf-eating beetle that attacks potatoes and other plants in the nightshade family, especially eggplants and sometimes…
📄️ Crown Rot
Crown rot is a general name for decay at a plant’s crown: the junction where stems meet roots, usually at or just below the soil surface. It is not a single…
📄️ Cucumber Beetles
Cucumber beetles are small leaf beetles that feed on cucumbers, melons, squash, pumpkins, and other cucurbits. In North American gardens, the two familiar…
📄️ Cutworms
Cutworms are caterpillars of several noctuid moth species, not a single species. They are named for their habit of cutting through young plant stems at or…
📄️ Damping Off
Damping off is a disease of seeds and young seedlings, not a single organism with one scientific name. It can be caused by several soilborne pathogens…
📄️ Deer
Deer are browsing mammals that feed on many garden plants. “Deer” refers to several species in the family Cervidae, rather than one species with a single…
📄️ Downy Mildew
Downy mildew is a group of plant diseases caused by several species of oomycetes, or water molds, rather than one fungus with a single scientific name…
📄️ Early Blight
Early blight is a fungal disease of tomatoes and potatoes. Despite its name, it can develop at any point in the growing season, though symptoms often become…
📄️ Earwigs
Earwigs are insects in the order Dermaptera. Several species visit gardens; the European earwig (Forficula auricularia) is a common one. They have elongated…
📄️ Fire Blight
Fire blight is a bacterial disease of plants in the rose family, especially apple, pear, quince, and some ornamental relatives. It can kill blossoms and young…
📄️ Flea Beetles
Flea beetles are a group of small leaf beetles named for their ability to jump when disturbed. Most adults are about 1.5–3 mm long, though size varies by…
📄️ Frost Damage
Frost damage is an injury caused when plant tissues become cold enough for ice to form or for cells to lose water to ice forming around them. It is an…
📄️ Fruit Cracking
Fruit cracking is a physiological disorder in which the skin of a developing or ripening fruit splits as the flesh expands faster than the skin can stretch…
📄️ Fungal Leaf Spot
Fungal leaf spot is a general name for diseases caused by many different fungi, not a single species. These fungi infect leaves and produce small areas of…
📄️ Fungus Gnats
Fungus gnats are small, dark flies commonly found around houseplants, seed trays, and damp potting mix. The plant-associated pests are usually dark-winged…
📄️ Fusarium Wilt
Fusarium wilt is a soilborne fungal disease that affects many garden crops and ornamentals, including tomatoes, beans, melons, and flowers. It is most…
📄️ Gray Mold
Gray mold, also called Botrytis blight, is a fungal disease caused most commonly by Botrytis cinerea. It affects many garden plants, including strawberries…
📄️ Iron Chlorosis
Iron chlorosis is a nutrient disorder in which a plant cannot obtain enough usable iron to make chlorophyll. It is not an infectious disease, and the soil may…
📄️ Japanese Beetle
The Japanese beetle is an introduced scarab beetle that feeds on many garden plants, including roses, grapes, beans, and fruit trees. Adults are about 10 mm…
📄️ Late Blight
Late blight is a fast-spreading disease of tomatoes and potatoes caused by Phytophthora infestans, a water mold rather than a true fungus. It thrives in cool…
📄️ Leaf Miners
Leaf miners are the larvae of several kinds of flies, moths, beetles, and sawflies, rather than a single species with one scientific name. They feed between…
📄️ Leaf Scorch
Leaf scorch is a description of leaf damage, not a single disease with a scientific name. It develops when leaves lose water faster than the roots can replace…
📄️ Mealybugs
Mealybugs are small, sap-feeding insects in the family Pseudococcidae. They occur on many houseplants, ornamentals, fruit crops, and greenhouse plants. Most…
📄️ Mosaic Virus
Mosaic virus is a common name for diseases caused by several different plant viruses, not one species with a single scientific name. They affect vegetables…
📄️ Nitrogen Deficiency
Nitrogen deficiency is a shortage of plant-available nitrogen, an essential nutrient used to make chlorophyll, proteins, and new growth. It is a nutritional…
📄️ Onion Fly
Onion fly is a small gray fly whose larvae, often called onion maggots, feed on onions and related alliums, including shallots, garlic, and leeks. Adults lay…
📄️ Overwatering
Overwatering occurs when soil stays wet long enough to limit the oxygen available to plant roots. Roots need oxygen to function; in waterlogged soil, they…
📄️ Peach Leaf Curl
Peach leaf curl is a fungal disease of peach and nectarine trees caused by Taphrina deformans. The fungus survives on bark and bud surfaces, then infects…
📄️ Poor Pollination
Poor pollination occurs when too little viable pollen reaches a flower’s receptive stigma, or when pollen fails to fertilize enough ovules. Flowers may fall…
📄️ Powdery Mildew
Powdery mildew is a group of fungal diseases, not a single species. Different fungi infect different hosts, including roses, squash, cucumbers, grapes, and…
📄️ Rabbits
Rabbits are plant-eating mammals that browse gardens, especially where tender growth is easy to reach. “Rabbits” describes several species rather than one…
📄️ Root-Knot Nematodes
Root-knot nematodes are microscopic roundworms that live in soil and feed inside plant roots. Several species in the genus Meloidogyne attack vegetables…
📄️ Root Rot
Root rot is a general name for the decay of plant roots, not a single disease with one scientific name. It can result from prolonged waterlogging and lack of…
📄️ Rust
Rust is a group of plant diseases caused by fungi in the order Pucciniales, not a single species. Different rust fungi infect different hosts, including…
📄️ Sawfly Larvae
Sawfly larvae are the immature stages of sawflies, a group of insects related to wasps and bees. Most garden species feed on leaves or conifer needles…
📄️ Scale Insects
Scale insects are small, sap-feeding insects that settle on garden and houseplants. Adults often look like bumps on leaves, twigs, or stems rather than…
📄️ Septoria Leaf Spot
Septoria leaf spot is a fungal disease caused by species of Septoria. It affects many garden plants; the species responsible depends on the host. On tomatoes…
📄️ Slugs and Snails
Slugs and snails are soft-bodied mollusks that feed on many garden plants. Snails carry a visible shell; most slugs have no external shell. Both move on a…
📄️ Sooty Mold
Sooty mold is a common name for several dark-colored fungi, not a single species. They grow on sugary honeydew left by sap-feeding insects such as aphids…
📄️ Spider Mites
Spider mites are tiny, plant-feeding arachnids in the family Tetranychidae, not insects. Several species attack garden and houseplants; the two-spotted spider…
📄️ Squash Bugs
Squash bugs are sap-feeding insects that attack squash, pumpkins, and other cucurbits. Adults and nymphs pierce plant tissue and suck out sap, especially from…
📄️ Squash Vine Borer
The squash vine borer is a clearwing moth whose caterpillars tunnel inside squash stems. It primarily attacks summer squash, zucchini, pumpkins, and other…
📄️ Sunscald
Sunscald is noninfectious injury caused when direct sunlight heats plant tissue beyond what it can tolerate. It often follows a sudden increase in exposure…
📄️ Thrips
Thrips are tiny, slender insects in the order Thysanoptera. Many species feed on garden plants, including vegetables, fruit, and ornamentals, although some…
📄️ Tomato Hornworm
The tomato hornworm is the caterpillar of a large sphinx moth. Despite its name, it also feeds on other plants in the nightshade family, including peppers…
📄️ Transplant Shock
Transplant shock is a temporary setback that occurs when a plant is moved and its roots cannot take up enough water to support its leaves and new growth…
📄️ Underwatering
Underwatering is a shortage of water available to a plant’s roots. It occurs when rainfall or irrigation fails to replace water lost from soil and leaves, or…
📄️ Verticillium Wilt
Verticillium wilt is a soilborne disease caused mainly by the fungi Verticillium dahliae and V. albo-atrum. The fungi enter through roots and grow in the…
📄️ Vine Weevil
Vine weevil, also called black vine weevil, is a beetle that damages many garden and container plants, including rhododendrons, heucheras, strawberries and…
📄️ Whiteflies
Whiteflies are a family of tiny, sap-feeding insects that infest vegetables, ornamentals, and greenhouse plants. Despite their name and mothlike appearance…