The plant is only known to occur at two sites (considered as one location due to the threat of habitat destruction associated with tourism) covering a very small area in the island of Elafonisos. The species was first assessed in The Red Data Book of Greece as Endangered (Phitos and Kamari 1995) due to its limited distribution and the rapid touristic development of the island, that was thought to result to its extinction at the time. Later, Saponaria jagelii was assessed as Critically Endangered in 2006, based on criteria B1ab(i,ii,iii,v)+2ab(i,ii,iii,v) (Iatroú 2013). Due to the situation that human activities are still causing a lot of damage and continued decline to the species' area, extent and quality of habitat (touristic development could possibly cause a population decline of up to 80% in the next 10 years), there are no laws to protect the species, no management plans have been designed so far by the state and a decline in the population has been observed in the last four years, this species is assessed as Critically Endangered under B1ab(i,ii,iii,v)+2ab(i,ii,iii,v).

Saponaria jagelii is a very rare Greek endemic, that grows in the western part of the Greek island of Elafonisos, which is a small island covering about 25 km², located 600 m off the southern coast of the Peloponnese. It grows on sand dunes exclusively (Phitos and Greuter 1993, Phitos and Kamari 1995, Montmollin and Strahm 2005, Iatroú 2013).

According to the report of the project "Species on the brink of extinction - SoBEx" (Kougioumoutzis 2019), the population of Saponaria jagelii consisted of 1,815 individuals in total, 1,651 of them being mature. The population exists in two sites. The first hosted 1,567 individuals in 2019, 1,407 of them mature and 160 young plants. The second site hosted 248 individuals, 244 of them mature. A second survey (Stefi and Thanos 2023) was carried out for two consecutive years (2022 and 2023) and did not detect a single individual of the smaller population at the second site (248 individuals in 2019), located at a beach highly accessible by visitors and tourists etc, and it is possible that the plant may have been lost from that site for good. On the other hand, the largest population of S. jagelii, was found thriving during their recent visit (April 1-3, 2023). In fact an individual plant census returned a somewhat (by 5%) higher value (ca 1,520 individuals), compared to that of 2022 (ca 1,440) and almost equal to the 2019 size (1,567 individuals). Furthermore, it is noteworthy that the population has expanded to some extent towards the sea, where a large number of individuals - not just clusters - were detected, although lots of litter (mostly dead, semi-decomposed aquatic plants and animals as well human garbage) washed ashore by the south winds, often cover part of the beach where S. jagelii occurs. Additionally, data from previous years indicate that 10-20% of the entire subpopulation was growing within a private property, while during the 2023 visit only 4-5 individuals were counted.

This annual is only known to occur on this island where it grows in two scattered, very restricted localities directly on the sandy sea-shore. It is part of the characteristic plant community growing in disturbed conditions along sandy beaches, together with Ammophila arenaria, Euphorbia paralias, Medicago marina and Silene sedoides. It is related to Saponaria calabrica, but differs from the latter in a number of characters.

Tourism is rapidly developing on the island and human activities on the beach, such as driving motor vehicles and trampling, represent a major threat, especially during S. jagelii's flowering period. This increase in tourism could result in a decline of the population or even its extinction within a short time. However, the species should be able to tolerate a moderate number of tourists during the main vacation season after the end of May, when its seed capsules are already ripe. At that time, some exposure to trampling could even be beneficial for seed dispersal (Iatroú 2013). During 2023, Stefi and Thanos observed that the plants showed that they were being grazed and they counted 48 individuals, partially grazed. Climate change could also affect the tiny species' habitat in Elafonisos, especially if the sea level rises in the future.

This species is not included in any international conventions or national legislation, although it is in the list of the Top 50 Mediterranean island plants, at the brink of extinction (Montmollin and Strahm 2005). The plant is included in Natura 2000 site GR 2540002 (Periochi Neapolis kai Nisos Elafonisos), which gives it indirect protection. However, no measures for the habitat protection have been taken yet. Since it is probably not feasible to prevent tourists from accessing the beach, cars at least should be forbidden. Ideally, its habitat should not be accessible during the plant's germination from seeds to the completion of the fruit set, which is from early May to early June (Iatroú 2013). Stefi and Thanos (2023) collected 100 subcylindrical capsules with ripening seeds (around 10 seeds per capsule), for both research and long-term storage in Seed Banks (NKUA and MSB Kew), in the framework of a satellite assignment to the “Conserving the Flora of the Balkans: Native Plants of Greece” Project. Successful germination has also been achieved. This is crucial for the species' recovery. Continuing the monitoring of the population for several years along with planning its recovery and management of the area it occupies, are extremely urgent. Citizens' awareness and communication of the significance of this plant for the country's environment will also play a huge role for its survival. The state has to protect Saponaria jagelii under national and international laws.