The oleander shrub or tree belongs to the dogbane family Apocynaceae and genus Nerium. Oleander is one of the most poisonous commonly grown garden plants. Caterpillars of the polka-dot wasp moth (Syntomeida epilais), common crow butterfly (Euploea core) and oleander hawk moth (Daphnis nerii) feed oleanders and retain or modify toxins, making them unpalatable to predators such as birds, but not to certain spiders and wasps.
The flowers have an attractive but deceptive corolla that attracts pollinators as the flowers have no nectar. Pollinators are required for the seed set. Oleander leaf scorch – a bacterial disease - has also become a serious threat to the shrub.