This tree naturally grows in mossy forests of various provinces and localities in Indonesia, Philippines, and Malaysia. It has a calculated extent of occurrence (EOO) of 3,892,008.889 km² which account for its 21 estimated locations based on currently available information. Though its population size is currently not known, a continuous decline is expected due to habitat-threatening effects of urbanization, small-scale and large-scale logging operations, shifting agriculture and other unsustainable farming practices, and the over-exploitation of the species for its vital purposes. However, despite these threats affecting the population and natural habitat quality, it is assessed globally as Least Concern (LC) given its numerous occurrences, very wide distribution, and expected abundance. But still, its conservation both, in situ and ex situ would be an essential initiative in preventing the species from being pushed into any threatened category in the future.

This species is native to Malaysia, Indonesia and the Philippines. It is a tree that grows in mossy forests as well as low to high montane primary and secondary forests (Merrill 1923). With the best available data, it is known to have at least 65 localities distributed over the Philippines (Palawan, Negros Occidental, Camiguin, Misamis Occidental, Bukidnon, Davao del Sur, South Cotabato), Malaysia (Pahang and Sabah), and Indonesia (Aceh, North Sumatra, West Sumatra, Bengkulu, South Sumatra, Jambi, West Kalimantan, Central Kalimantan, East Kalimantan, Banten, West Java, Central Java, East Java). Its extent of occurrence (EOO) is 3,892,008.889 km² (GBIF 2022). The species is primarily threatened by land conversion and habitat degradation due to commodity driven deforestation, forestry related activities, urbanization, and shifting cultivation (GFW 2022).

There is no information on the population size of the species. However, a decline is suspected due to continuous loss of primary forests within its distribution range.

Rhododendron javanicum is an epiphyte, shrub or small tree. It has two known subspecies, palawanense and schadenbergii. The former can be found in Mt. Matalingahan, Palawan, while the latter is more widely distributed over the Philippines and Sumatra to Sulawesi, Indonesia (International Dendrology Society 2022). The species can be generally found in low to high montane primary and secondary mossy forests, also near volcanic craters, narrow ridge crests, steep slopes, in rather dry grounds, between rocks, along streams, etc. It occurs in elevations of about 600–2,900m. It is mostly epiphytic, but on Mt Apo it was also reported as a terrestrial shrub (Merrill 1923, Pelser et al. 2011). It is characterized by its orange to red flowers, oblong-elliptical obtuse leaves, which are but slightly lepidote beneath, and its glabrous ovaries (Copeland 1929).

Rhododendron javanicum is primarily threatened by land conversion and habitat degradation brought by commodity-driven deforestation, shifting cultivation, urbanization, and forestry activities such as logging. A significant loss of natural forests due to land use change was reported in its localities based on the analyzed data from the Global Forest Watch (2022). As of 2020, the forest cover lost in the species localities in the Philippines is approximately 163,000 ha in Palawan, 7,630 ha in Negros Occidental, 217 ha in Camiguin, 5,180 ha in Misamis Occidental, 23,800 ha in Bukidnon, 17,200 ha in Davao del Sur, and 13,800 ha in South Cotabato while in Malaysia, it is about 22,000 ha in Pahang and 21,600 ha in Sabah. In Indonesia, the lost cover is estimated to be 8,730 ha in Aceh, 6,280 ha in North Sumatra, 7,930 ha in West Sumatra, 3,540 ha in Bengkulu, 7,240 ha in South Sumatra, 24,100 ha in Jambi, 32,000 ha in West Kalimantan, 47,600 ha in Central Kalimantan, 38,800 ha in East Kalimantan, 57.4 ha in Banten, 129 ha in West Java, 34.8 ha in Central Java, and 980 ha in East Java. Interventions and conservation actions are highly recommended to prevent further tree cover loss and population decline.

There is no information on the trade and use of the species.

Rhododendron javanicum subsp. palawanense was included in the DAO 2017-11 or the Updated National List of Threatened Species in the Philippines assessed as Critically endangered while the subsp. schadenbergii is endangered (DENR 2017). Through this administrative order pursuant to Republic Act no. 9147 or the Wildlife Resources Conservation and Protection Act of 2001, illegal and excessive tampering of the species from its natural habitats, together with other species specified therein, are inhibited. Its unauthorized utilization, trade, and disturbances made in its natural habitats are punishable by the law. Furthermore, subpopulations of the species are protected in-situ since they are within protected areas (PAs), Northern Negros Natural Park, Palawan Flora, Fauna and Watershed Forest Reserve (Parcel 2), Mt. Malindang Natural Park, Mt. Kitanglad Range Natural Park, Mt. Apo Natural Park, Mt. Matutum Protected Landscape, Allah Valley Watershed Forest Reserve. It can also be found in the following protected areas: Kerinci Seblat National Park, Ujung Kulon National Park, Mount Halimun Salak National Park, Mount Merbabu National Park, Taman Nasional Gunung Merapi, Bromo Tengger Semeru National Park. In addition, it is known in at least 37 botanic gardens globally as ex situ collection (BGCI 2022). Further inventory and research are needed to account for its remaining population size in the wild. This will help in creating a relevant conservation action plan.