If either ingested or touched, dieffenbachia can cause negative reactions. The symptoms range from moderate to severe and can be dangerous if airways are blocked. Due to the calcium oxalate contained in this plant, its leaves and sap have toxic properties. When ingested, they can induce symptoms such as lip and tongue swelling, drooling, speech loss, and difficulty breathing; when touched, they can cause a painful skin rash or eye irritation. Since these plants are often found indoors as decorative plants, be careful when keeping them around small children. Always wear gloves when handling this plant.

As a plant with beautiful flowers, tobacco should be planted with caution due to its high toxicity to both humans and animals through ingestion.

Eastern Pasqueflower is a small, clumping perennial with blue-violet bell-shaped flowers. The attractive blooms are followed by fluffy, striking seed heads. These pretty flowers are easy to grow in dry, sunny areas.

Striped barbados lily is perennial herbs with showy flowers but it contains toxic compounds, most notably alkaloids lycorine and tazetine, as well as calcium oxalate crystals.

The heart of jesus plant has a name that implies purity, but it is actually toxic. Like other Caladiums, its sap is extremely irritating when eaten or even just applied to the skin. A painful, itchy rash breaks out on contact. That rash is essentially what a person who ingests it will experience as well, except inside of their mouths and all the way down their digestive tracts. Besides a great deal of pain and irritation, this causes severe nausea, excessive salivation, vomiting and diarrhea, and also significant swelling in many cases. Keep this plant away from children.

Durian (Durio zibethinus) is a tropical plant from Southeast Asia. It bears large, spiny, edible fruit which has become a major export crop of the region. The fruit is best known for its pungent smell, which provokes opposing reactions, ranging from near-addiction to revulsion. In some areas, it has even been banned from public transport and hotels.

Poisoning symptoms from sierra Larkspur (genus Delphinium glaucum) could become a medical emergency, as these plants are incredibly toxic to dogs. All parts contain toxic alkaloids, though these are usually most concentrated in the new, green growth of younger plants. Symptoms following ingestion are many and varied, ranging from excessive drooling, vomiting, diarrhea, lethargy, and stiffness to irregular heartbeat, seizures, respiratory difficulty or failure, paralysis or even death. Seek medical treatment for your dog if it has consumed sierra Larkspur, even if no symptoms are immediately present.

Bird of paradise is generally considered non-toxic but can be poisonous when ingested in large quantities. Cases of poisoning are typically mild to moderate with symptoms including abdominal cramps, nausea, vomiting, and diarrhea. Cases of poisoning may be more serious in children. The fruit and seeds are considered to be the most toxic parts of the plant. The frequent use of this plant as a houseplant could be a factor in poisoning frequency. This plant can be mistaken for another more toxic species, Poinciana gilliesii, as they share the same common name, bird of paradise.

Honeyberry is a plant native to the Northern Hemisphere, and bears long, waxy fruits. These blue-colored fruits are edible, and their taste is described as a combination of blueberries and raspberries. This Lonicera caerulea produces fruits within the first year of planting, and thrives in colder climates.

Cutleaf anemone (Anemone multifida) is a flowering plant species native to North America and related to the buttercup. The cutleaf anemone is poisonous and contains ranunculin. This species comes in four subspecies variations.

Resin spurge (Euphorbia resinifera) can be found living in the densely forested regions of Morocco. This species is incredibly easy to grow and can tolerate many soils, even if they're dry and nutrient-deficient. This makes it a prime choice for use as a houseplant. However, it can cause a rash if mishandled.

Lily of the valley is highly poisonous and originates in Eurasia. Although it is toxic, it is popular in gardens and the perfume industry for its charming flowers and fragrance. Lily of the valley is the national flower of Finland and was the national flower of former Yugoslavia.

Sweet pea is a staple of flowering climbers and has been since the Victorian era. The sweet pea, which uses tendrils to climb when correct supports are available, grows to a height of 1.02 m – 2 m. The highly fragrant flowers are purple when found in the wild, but domesticated cultivars can be found in nearly every color.

True to this plant's reputation, consumption of potato can be extremely toxic to dogs, and warrants immediate veterinary attention. All parts of these plants contain several toxic substances which can cause loss of appetite, excessive drooling, vomiting, diarrhea, dilated pupils, confusion, behavioral changes, and weakness. In more severe cases, difficulty breathing, a lowered heart rate, coma, or even death may occur, so treat it as a medical emergency if your pet has come into contact with this plant.

Opium poppy (*Papaver somniferum*) was first cultivated approximately 5,400 years ago by the lower Mesopotamians. The Sumerians called it “Hul Gil,” which means the “joy plant.” It is used in the production of medical painkillers. The tiny seeds are commonly added as a topping on bread buns, but most portions of the plant are toxic if eaten.

Evergreen azalea are members of the Rhododendron genus, all of which contain varying levels of a toxin known as Grayanotoxin in all tissues. Physical contact can cause a rash in sensitive people, the pollen can irritate mucus membranes, and ingesting it can cause nausea, vomiting, arrhythmia, low blood pressure, and hallucinations in humans. Grayanotoxin is so strong that even the amounts contained in honey made from Rhododendron pollen can have negative effects.

Poisoning symptoms from candle larkspur (genus Delphinium elatum) could become a medical emergency, as these plants are incredibly toxic to dogs. All parts contain toxic alkaloids, though these are usually most concentrated in the new, green growth of younger plants. Symptoms following ingestion are many and varied, ranging from excessive drooling, vomiting, diarrhea, lethargy, and stiffness to irregular heartbeat, seizures, respiratory difficulty or failure, paralysis or even death. Seek medical treatment for your dog if it has consumed candle larkspur, even if no symptoms are immediately present.

Viper's bugloss (Echium vulgare) is a member of the borage family and attracts honeybees. Once established, this pretty blue wildflower is easy to grow. However, it can become invasive. This species has a deep taproot which makes it difficult to transplant and difficult to eradicate.

Plants of genus Buxus are widely present around the world as а hedge or garden ornamental plants, but they contain alkaloids, most notably buxin, which are toxic to animals.

All parts of common foxglove are severely toxic to humans when ingested, including the flowers, leaves, roots, and stem. Symptoms of poisoning may include nausea, vomiting, diarrhea, stomach pain, headache, irregular or slow heart rate, tremors, color hallucinations, and convulsions. Consumption of can be fatal. Common foxglove is sometimes cultivated as an ornamental plant in gardens, and poisoning is most likely to occur from accidental consumption by children.