Neelakurinji, a mass flowering plant which blooms once in twelve years, grows in abundance in the Eravikulam Park. The park is a must-visit place during the kurinji flowering season.
Large number of rare varieties of plants, quite endemic to the Western Ghats, grows in the park. Recently the park gave good news for nature lovers when a rare species of orchid named Brachycorythis wightii was discovered there. The variety has almost been driven to the brink of extinction. Another rare orchid variety found in the park is Habenarea flabelliformis. Besides medicinal plants such as Drosera peltata there are wild varieties of cultivated plants like Piper schmidtti and Elateria cardamomum in the park.
There are several temperate species in the park including Mahonia leschnaultti, Rhododendron arboreum, Gaultheria fragrantissima and Berberis tinctoria.
Grasslands, shrub land and forests are the three major types of plant communities in the park. The high plateau and hills are covered by grasslands predominantly. While shrub lands are along the bases of the cliffs, the shola forests are found in the valleys and folds. The park boasts of the largest contiguous and undisturbed Shola grass land ecosystem where orchids and balsams can be spotted in abundance and variety.