The Green Heath, Erica sessiliflora, is one of the unmistakable heathers of the fynbos. With over 600 species of Erica in the fynbos of the Cape Floristic Region it is not surprising to find that each species will share at least some characters in common with other species. Erica sessiliflora though is the only species of Erica that retains its seeds on the plant for several seasons until a fire comes through. The seeds are retained in congested cone-like structures and this character is known as serotiny. While serotiny is common in members of the Proteaceae such as Leucadendron, it is unknown in Erica except for Erica sessiliflora.
Erica sessiliflora is also one of the most beautiful of the Cape heaths. It has long-tubed lime green flowers. And while green flowers may not sound attractive, these are almost luminescent within the fynbos. The flowers appear at the top of the stems in congested racemes. The base of the flowers, the calyx is tight to the stem, without a distinct flowerstalk. A term known as sessile and for which it has received its scientific name. It is this basal part of the flower that swells and hardens, the individual seed capsules merging into a tight cone around the stem. These capsules are often reddish but fade over the years they are retained. The growing point continues above the cone and so subsequent years’ cones appear some distance above.
Erica sessiliflora likes to grow where there is a bit of moisture in the soil but not too wet. At Phillipskop it particularly likes the slopes alongside the Saddle Hiking Trail and Panorama Path, where it produces quite a show when in flower. One or two plants can sometimes be found in flower at any time of the year but it has two peak flowering times, one in July and August and the other in February-March. It is unusual for fynbos plants to have this dual flowering. It can be easily mistaken for another greenish flowered Erica at Phillipskop, Erica viscaria. This species too has long tubed flowers in dense spikes but they are more yellowish white and often sticky to the touch. Erica viscaria flowers between January and April, so you can find both species in flower at the same time. But most significantly, it does not form the cone structures that are diagnostic for Erica sessiliflora.