Golden dewdrops (Duranta erecta) is an ornamental sprawling shrub commonly found in subtropical and tropical gardens all over the world. Its gentle purple blossoms are often visited by butterflies and hummingbirds. Golden dewdrops is considered a weed in Australia, South Africa and certain parts of East Asia.

The castor bean is important for its oil which is used as a lubricant, biodiesel ingredient, and rodent repellent, among other applications. The plants are now commercially planted globally, with India producing nearly 75% of the world's castor oil. Castor beans cannot be eaten because they contain a potent poison that's released if the seed is broken.

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.

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.

All parts of the evergreen spindle are considered toxic if ingested in large quantities. Symptoms can range from mild to life-threatening including vomiting, weakness, diarrhea, chills, convulsions, and coma. Since these plants are commonly used as ornamental hedges, you should be mindful of any children who may encounter the plant, be attracted by its colorful leaves and flowers, and may be tempted to eat them.

Brazilian peppertree (Schinus terebinthifolia) is a flowering plant native to South America that is related to the cashew. Brazilian peppertree is widely cultivated as a houseplant in regions without frost. The plant can cause skin irritation in people with sensitive skin.

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.

As the name infers, the poison hemlock is a highly poisonous plant and has been known to intoxicate a variety of livestock. The leaves are similar to carrots and parsley, fooling most herbivores into consuming it. Poison hemlock can be lethal when ingested.

Fairy crassula (Crassula multicava) is a plant species native to the mountainous region of Natal, South Africa. Fairy crassula blooms in spring. This species is often cultivated for ornamental purposes in pots and planters.

Although its berries look juicy and tempting, the fruits and the root of pokeweed are toxic and should not be eaten. Pokeweed is considered a pest species by farmers but is nevertheless often grown as an ornamental plant. Its berries can be made into pokeberry ink as well.

Oleander is moderately to highly toxic to humans – instances of ingestion, or physical contact with this plant's sap, should be immediately addressed by medical professionals. While fatal cases of oleander poisoning are very rare, they are possible. All parts of this plant are toxic if ingested. Physical contact with the plant's sap, which is found throughout the plant and is more likely to be exposed if the plant is cut or damaged, may cause dermatological symptoms, including redness and itchiness of the skin. Symptoms following ingestion include low blood pressure, lethargy, an irregular heartbeat, blurred vision, confusion, diarrhea, vomiting, dizziness, fainting and, in extreme cases, death. Be mindful of curious children, as oleanders are an extremely common ornamental plant cultivated in gardens and parks around the world.

Many species within the Cycas revoluta genus are highly toxic to dogs - if you suspect your dog has ingested any part of a sago palm plant, you should contact a vet immediately. The Sago palm is a very common ornamental and is the most common culprit. These plants contain high concentrations of the cycasin toxin, which is found throughout their structures but is most concentrated in their seeds. Ingesting even a small amount of cycasin can cause vomiting and diarrhea. Larger amounts can cause damage to the intestines and liver, coma, or death.

Slender false garlic (Nothoscordum gracile) is a herbaceous perennial that will grow to 51 cm tall. It blooms from spring to summer with clusters of small white flowers with purple stripes and colorful green and gold stamens. Flowers bloom at the top of the stem. Considered a weed it is commonly found growing along sandy roadsides and woods. Attracts bees and other pollinators.

Cape gooseberry (Physalis peruviana) is a perennial shrub species native to South America. This species has been cultivated by humans for a very long time, and can be traced to the Incan civilization. Cape gooseberry grows optimally in fertile, slightly acidic soil in full sun.

Spanish broom is a deciduous shrub native to the Mediterranean, West Asia, and North Africa. Fragrant yellow pea-like flowers cover the shoots in late spring and summer. It is cultivated for its ornamental value and is used for flavoring and essential oil extraction.

A garden poppy that can escape as a scrambling weed across open fields, the common fumitory (Fumaria officinalis) produces flowers from early spring to late fall. In the past, it had been used as a folk medicine, but it is now known to be poisonous and should not be used in any home remedies.

Lady of the night (Brunfelsia uniflora) is an evergreen tropical tree that will grow from 2.5 to 7 m tall. It blooms in spring with highly-fragrant, yellowish-white flowers. Perfume is made from the oil of the flowers. Blossoms attract butterflies and moths. Native to the Amazon, it prefers partial shade and moist, well-drained, slightly acidic soil.

Sticky Nightshade has been cultivated for centuries as a trap crop for potato nematodes, but it's becoming a more popular garden plant thanks to its tomato-like fruit, called "litchi tomato." This fleshy fruit has been used as food among indigenous tribes in South America. Many of the Solanum species are toxic, so you should be careful not to confuse the edible Solanum sisymbriifolium with some other species, especially the highly poisonous Solanum carolinense.

Tasmanian blue gum (Eucalyptus globulus) is an evergreen tree that can grow to over 61 m tall. Blooms from fall to spring with yellowish white flowers. Flower buds have a warty cap that falls off to release the numerous brush-like stamens. Attracts bees hummingbirds and other pollinators. Grows in full sun and is a great specimen for parks and city courtyards.

Moth plant (Araujia sericifera) is a perennial vine native to South America. Moth plant has been introduced around the world. This species is used as a food source for monarch butterflies, although it is not their preferred food.