'Sky' and 'Lydenburg' are two of the most floriferous and attractive
forms of agapanthus to grace the summer garden. Both were thought
to be forms of Agapanthus inapertus subsp. hollandii,
but recent studies show that 'Lydenburg' may be a hybrid. Like all
other forms of A. inapertus they are deciduous and prefer
inapertus subsp. hollandii has six to eight strap-shaped
leaves per plant, produced on a distinct stem. The plants are deciduous
with the leaves disappearing entirely in winter. The tuberous rhizomes
gradually spread, forming substantial clumps. The flower stalks
are held erect at the bud stage and become droopy as the flowers
open. The flowers are tubular and this subspecies has distinctly
flared, narrower perianth segments which are shorter than the length
of the perianth tube.
The form 'Sky` has pale, sky-blue flowerheads borne on erect, tall
stalks. Flowers occur from January to March and follow after those
of the evergreen species, A. praecox in the garden.. The
attractive greyish upright leaves, coupled with the elegant bearing
of the inflorescence, make this a very suitable plant for the border.
Although it prefers full sun, it will also flourish where it receives
late afternoon shade, and the pale flowers are particularly attractive
in the gentle light.
'Sky' was originally collected in the Lydenburg district and has
grown at Kirstenbosch for many years (Graham Duncan pers.comm.).
Agapanthus 'Lydenburg' has strikingly beautiful, deep blue
flowers which are long lasting and make this one of the most attractive
of all the deciduous agapanthus forms cultivated at Kirstenbosch.
New research (Zonneveld & Duncan 2003) suggests that it is not
a form of A.inapertus subsp hollandii, but a hybrid
between this subspecies and another of the A.inapertus subspecies.
The flowers are complemented by fresh green leaves, which like those
of 'Sky', are neat and not too large.
Apapanthus inapertus subsp. hollandii occurs in Mpumalanga.
This is the summer rainfall region of South Africa and plants are
found growing naturally in the Lydenburg , Graskop and Pilgrim's
Rest areas, on well-drained soils in open grassland. These areas
are at fairly high altitudes and receive plentiful summer rain.
Summers are hot; 28-30°C and winters cold and frosty. Both
'Lydenburg' and 'Sky' respond well to cultivation and do not rot
in winter rainfall regions, provided they have good drainage.
Agapanthus inapertus is
one of ten (new research suggests this might be reduced to six)
species of Agapanthus found in South Africa. They include
the well known A. praecox, A.
caulescens, A. coddii, A. africanus
and A. campanulatus. A. inapertus is one of the
lesser known species, yet its five subspecies include some most
attractive garden plants, including the inky blue A.
inapertus subsp. pendulus
The subspecies hollandii was first discovered in 1929 by
F. H. Holland, hence the specific name.
The pendulous species of agapanthus are pollinated by sunbirds as
well as insects. The seed once released is wind dispersed.
Uses and cultural aspects
The local people boil parts of agapanthus and add it to bathwater
to improve a person's luck.
Growing Agapanthus 'Sky' and 'Lydenburg'
Both `Sky` and 'Lydenburg' are well suited to mass display or
smaller groups in a mixed border. They are also ideal as container
subjects . Being deciduous they can be interplanted with such plants
as Chasmanthe floribunda
is winter growing and dormant in the summer. Lobelia anceps,
treated as an annual, flowers in summer, producing light blue flowers
and is ideal in a mixed border with Agapanthus `Sky`.
Both these agapanthus require a well-drained, fertile soil . They
need to be cut back at the end of the growing season, removing all
of the dried leaves and flower spikes. A generous layer of mature
compost can be scattered over the surface of the dormant agapanthus.
Agapanthus are water wise and do not require excessive watering.
Once a week is quite adequate. Approximately every eight years,
Agapanthus `Sky` and 'Lydenburg' need to be lifted after
flowering and each clump divided Each division should have at least
two growing points. For propagation purposes one growing point is
sufficient. Dividing stimulates flowering and within two growing
seasons the plants will be back to their best, producing an abundance
The other method of propagation is from seed. Unfortunately agapanthus
plants cross pollinate readily and consequently one is never sure
of what the seed will produce. Seed needs to be sown soon after
it is collected, or stored in the fridge (not freezer) until spring.
Seed should be sown in deep trays in semi-shade and kept moist.
Fresh seed should germinate in 6-8 weeks. Seedlings should be thinned,
but not transplanted from their seed trays until the following year.
Plants grown from seed will take about four years to flower.
Generally agapanthus are not bothered with pests, but the leaves
and flower buds can be affected by red spider mite, mealybugs, thrips
and gall midge fly. Apply a full cover spray with a contact insecticide
as soon as pests are observed and repeat every two weeks until the
infestation has been eliminated.
- Duncan, G.D. 1998. Grow agapanthus. Kirstenbosch Gardening
Series. National Botanical Institute, Cape Town.
- Leighton, F.M. 1965. The genus Agapanthus L'Héritier.
Journal of South African Botany, Suppl. vol. 4.
- Zonneveld, B.J.M. & Duncan, G.D. 2003. Taxonomic implications
of genome size and pollen colour and vitality for species of Agapanthus
L'Héritier (Agapanthaceae). Plant Systematics &
Evolution 2141:1 15-123.
John Winter & Yvonne Reynolds
Kirstenbosch National Botanical Garden