All parts of the oleander plant are poisonous, including the seeds.
Many common plant species contain poisonous seeds, leaves, stems or other parts. Before letting animals and small children run unsupervised in the yard or garden, check the area for poisonous plants. Many harmful or even deadly plants may appear attractive and harmless. Plant seeds in particular may be appealing to young children, who may eat them unsuspectingly, thinking or pretending that they are berries.
Castor Bean
As noted by the University of Arkansas Division of Agriculture, "everything about the castor bean is bold and a bit audacious," including its poisonous seeds. The castor bean plant, also known as the mole bean, is native to tropical Africa and is a common ornamental plant. Chewing just one of its seeds, which contain a poison called ricin, results in severe symptoms such as diarrhea, vomiting, dehydration and drop in blood pressure. Death can result in less than five days. The plant is especially dangerous for children, who are more susceptible to deadly dehydration.
Larkspur
Larkspur is another common ornamental plant species. Its vibrant purple, red, pink or white flowers are popular in landscapes and in flower bouquets. All of the plant's parts are poisonous, but its seeds contain the highest concentrations of poison. Symptoms of larkspur poisoning include salivation, muscular twitches, nausea and vomiting, bloating, nervousness and anxiety, and an increase in heart rate. In Western states, larkspur is a common cause of death in cattle, although it is not known to be fatal to humans.
Oleander
Oleander plant varieties are toxic in all their parts. The oleander is an attractive plant that is also quite hardy, making it common in gardens and in landscaping. In Sri Lanka, ingestion of yellow oleander seeds is a leading method of suicide. Ingestion of seeds causes a burning sensation in the mouth, nausea and vomiting, anxiety, vision changes, convulsions and comas.
Tags: poisonous seeds, castor bean, common ornamental, common ornamental plant, nausea vomiting, ornamental plant, parts oleander