The key pollinators of the genus Erica are insects, birds
and wind. Erica sessiliflora is pollinated by sunbirds. The sunbird inserts its
long, curved beak into the long tube-shaped flower and extracts nectar at the
base of the flower, and in turn its beak comes into contact with the pollen on
the anthers positioned in the mouth of the flower tube. The bird then transfers
the pollen to the stigma of another flower. The flowers are pollinated and seed
is produced.
Erica sessiliflora is most unusual among ericas as it is
serotinous, i.e. it retains its seed for several years on the bush. The
fruiting bodies may stay attached to a branch for up to seven years or until
the bush is burnt, whereupon the seed is released. The smoked seeds fall to the
ground and germinate in the autumn. Serotiny is an adaptation to survive fire
by storing the seeds in a fire-safe environment. Many fynbos species also store
their seeds on the bush for many years, but this is the only Erica that does
so.
Uses
Erica sessiliflora is not a medicinal or useful plant, but
is an excellent garden shrub. It attracts birds to the garden. Its flowers are
certainly a joy to admire and are long-lasting in a vase.
Growing Erica sessiliflora
Plant Erica sessiliflora in full sun, where there is free
circulation of air. Soil type should be free-draining, sandy and acidic with
low levels of phosphate. No manure should be used, rather feed with well-rotted
compost or slow-release or low-dose organic fertilizers. To increase acidity of
the soil, decomposed pine needles or pine bark can be mixed into the soil.
Remove weeds and grass before planting. Mulch with well-rotted compost or pine
bark after planting--this helps suppress weeds and prevents soil moisture from
evaporating. If weeds are removed from around the plant, hold the soil down
firmly around the weed first and then remove the weed; this helps prevent
disturbance to the delicate Erica roots. This plant is not a candidate for the
arid water-wise garden as it needs water all year round. The best time for
planting is in late summer to autumn (March to May), when the weather is
cooler. Prune plants regularly as this stimulates branching and removes
diseased material.
Erica sessiliflora growing at Kirstenbosch
Grow Erica sessiliflora in the fynbos garden where it looks
very attractive inter-planted with other fynbos species or planted en masse. It
is well suited to a region with a Mediterranean climate, and does well in
rockeries. E. sessiliflora is also suitable for pot cultivation, which is
recommended for gardens in colder climates, as the pot can be moved to a
protected position during the cold months. Good drainage is essential.
Erica sessiliflora can be propagated from either cuttings or
seed. A larger plant is achieved sooner from cuttings than from seed.
Take cuttings in autumn or spring. Semi-hard wood or heel
cuttings are best. A higher percentage of rooting is achieved if a rooting
hormone is applied. The recommended medium is equal parts of sifted bark and
polystyrene for good aeration. Place the cuttings in a mist unit with bottom
heat.
Sow seed in autumn (April-May) in 100 mm deep seed trays.
Erica sessiliflora seeds take longer to mature than in most other species, and
should be harvested from the fruiting heads that are one or two years old. A
higher percentage germination is achieved if the seeds are first treated with
Instant Smoke Plus Seed Primer or a similar smoke treatment. The soil medium
used should be acidic and well drained (e.g. equal parts of river sand and
sifted bark mixed together). Sow seeds thinly and evenly to prevent damping
off. This can be done by mixing seed with fine, dry sand before sowing and
spreading the sand and seed evenly over the seed tray. Cover with a thin layer
of sand after sowing. Water gently and keep the tray moist but not wet and out
of direct sunlight and rain. Germination occurs within 1-2 months. When the
seedlings are about 10 mm tall, move the tray to a lightly shaded position. Pot
up when they are 15-20 mm tall and keep lightly shaded and well watered until
hardened off (1-3 months). The young, established plants are then moved into
direct sunlight and grown on until large enough to be planted into the garden. Source : SANBI
