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Fishlegs: "They're very beautiful, very soft, perennial. And... Poisonous to reptiles!"
Hiccup: "Which means poisonous to dragons!"[src]
  — Fishlegs and Hiccup on Blue Oleanders  

The Blue Oleander is a type of flowering plant first seen in the Dragons: Riders of Berk television series.


In the DreamWorks Dragons Franchise, Blue Oleander is a short bushy plant with stunning blue flowers. Each flower is complete with five separated petals of equal size. The leaves are ovate and end in an acute tip. In the center, there is a short yellow stem for the purpose of pollination. They are usually seen planted in large clusters, sometimes stretching for field upon end, suggestive of a high pollination rate when in close proximity to one another.


Blue Oleander flowers seem to prefer full sun to grow, just like Dragon Root and Dragon Nip.

It is not clearly known why it is poisonous to reptiles. In the Franchise, Blue Oleander is fatally poisonous to reptiles (according to Chapter 8 of a botany book belonging to Fishlegs). However, Dragons are also noted as being allergic to these flowers. It is unknown if only the flowers are toxic or the entire plant. The ill effects on Dragons is not instantaneous. In "Dragon Flower", the plant's mere presence on Berk affects them, indicating that perhaps pollen is the culprit of illness and the first symptom is sneezing. However in "When Darkness Falls" and "Defenders of the Wing, Part 1", Dragons appear to be alright while in the vicinity of Blue Oleander. Despite being affected by the flower. Terrible Terrors even appear to be attracted to them.

Scauldrons are the only dragon species that suffer no ill effects from Blue Oleander and appear to love eating them. After eating Blue Oleander, Scauldron venom can cure other Dragons being afflicted with Blue Oleander. However, it was later discovered that the Blue Oleander also has an effect on Scauldrons. When Scauldrons eat too much Blue Oleander at one time, they can change its green color to blue color. Though this effect has been confirmed, it is unknown if the effect is only temporary or permanent. The most likely explanation is that the effect wears off as time goes by and the dragon has no exposure.

In actuality, a plant called "Oleander" (Nerium oleander) belonging to the Dogbane Family does exist. It has been used as an ornamental plant for over a thousand years. There is no blue variant, however; flowers are various shades of pinks and also white. They are small shrubs with lance-shaped leaves.

All parts of Nerium oleander are toxic to humans and most other animals, though its effects on reptiles are not described. Birds and rodents are somewhat tolerant of its effects. Nerium oleander toxicity can affect skin, nervous system, heart, and gastrointestinal tract.


Dragons: Riders of Berk

In the episode, "Dragon Flower", the villagers board Trader Johann's ship and start trading with him. Even Mildew is seen receiving a mysterious item in exchange for some cabbage. Later on, when the dragons begin falling mysteriously ill, the gang discover a bush of flowers, that was never seen before. Recalling from his botany book, Fishlegs identifies them as the Blue Oleander, a flower that is poisonous to reptiles, including dragons. Hiccup orders Fishlegs to retrieve the buried botany book from the pit to find an antidote. Later, it is found out that the dragons can be cured by the venom of a Scauldron.

Scauldrons are the known dragons that eat Blue Oleander flower.

When a Scauldron eats the Blue Oleander, the venom that it produces can be used as an antidote to cure the sick dragons. After a few events, the dragons are cured and they become their usual self.

Dragons: Race to the Edge

Season 1

In "When Darkness Falls", Blue Oleander reappears on one of the islands the Dragon Riders search for a base camp. They quickly leave before the flower takes effect on the dragons, though Barf & Belch sneeze once.

Season 3

The island, Botany Blight, had the Blue Oleander growing abundantly, which was why Viggo chose the location to discuss a truce with Hiccup without Toothless right by his side, in the episode, "Defenders of the Wing, Part 1" The quantity of Oleander prevented Toothless from getting too close, should the toxins from the oleanders poison him. It is unknown at what proximity a dragon must be to be affected by the oleander, as it differs per dragon and season.

Season 6

They are mentioned in the episode "Triple Cross" when Viggo Grimborn tricks Hiccup into feeding Toothless Red Oleander, which he says is even more deadly than Blue Oleander. In the end, Viggo admits that the Red Oleander is harmless, and he only said that to trick Hiccup into joining forces with him.


Dragons: Rise of Berk

Blue Oleander is mentioned only very briefly in this game and does not appear as a regular feature. An image of blue oleander, as well as other colored flowers, appear on the official Facebook page of the game as a quiz for players.

School of Dragons

Blue Oleander is only mentioned briefly in this game and is not seen. In a Stable Quest called "Why So Blue?" the player is asked to send a dragon with "venom that can heal others" because a number of other dragons have eaten blue oleander and gotten sick.

Sometimes the Stable Quests' travel log indicates that the dragons are "Flying over Scauldrons grazing on Blue Oleander ...".


  • The Blue Oleander shares a resemblance to the Rock Blossom needed for the Eel Pox cure from "The Eel Effect".
  • The Blue Oleander's cousin, the Purple Oleander, is not poisonous to reptiles, and in fact, can be used as a cure for concentrated dragon root poisoning.
  • Another of Blue Oleander's cousins, the Red Oleander, is also harmless to dragons, as Viggo Grimborn states in "Triple Cross".
  • The first Blue Oleander flowers were delivered by Johann to Mildew, but where Johann got the flowers may have been foreshadowing of his true villainous character that was revealed in Dragons: Race to the Edge, Season 5.
  • The Blue Oleander is the first plant in the series to be weaponized.


Wikipedia-logo-v2.svg.png Nerium on Wikipedia

Blue Oleander uses Creative Commons Licensed content from the Dreamworks School of Dragons Wiki page Stable Missions. The list of authors can be found on the page revision history (view authors). SODWikiLogo.png

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