True blue flowers are always special. Worldwide they are sought
after, a rare colour to find in a flower. The colour is striking
by itself, breathtaking in mass and always a wonderful contrast
to most other colours. Lobelia valida has deep blue flowers
throughout summer, a superb perennial for the garden.
The best time to find them in the wild is after fires when they
flower most conspicuously on the coastal dunes and limestone hills
from Bredasdorp to Riversdale in the Southern Cape. Here the locals
maintain that the flowering time coincides with the galjoen fishing
season (Nov to April), hence the common name, Galjoenblom.
Branching from the base, the long branches stand proud with their
blue flowers densely packed at the top of the stems. The plants
grow to about 40 to 60 cm. in height. The light green leaves, scattered
along the branches, are flat and soft with coarsely toothed edges.
blue flowers, crowded at the tops of the branches, are typical of
lobelia. Looking closely, one will see the flowers are two-lipped.
The upper lip has two small petals split to the base at the back,
and the lower lip has three larger petals. The lower petals are
marked with white and a blotch of bright yellow at the centre, clearly
guiding the nectar-feeding fly, which pollinates the flowers. These
long tongued flies are specially adapted with long sucking mouthparts
to collect nectar hidden at the base of a deep tube.
Growing Lobelia Valida
Lobelia valida grows easily in the garden given a sunny
position with light well- drained soil, enriched with compost. It
is ideal for coastal gardens. Flowering abundantly throughout summer
it is best to replace plants regularly, as the stems tend to get
untidy and woody at the base after a year's vigorous growth. Plants
live for about 3-4 years, but one might wish to replace them sooner
in the garden. For the best display, the plants should be planted
15cm apart. Lobelia also looks beautiful mixed with other summer
flowering perennials such as Pelargonium peltatum ( Ivy leave
geranium), Geranium incanum and Diascia integerrima.
Lobelia valida can be propagated by seed or cuttings. The
plants set seed freely, producing small little black seeds. The
seed can be sown any time of the year into seedtrays filled with
a well-drained medium. Sow the seeds thinly as the germination is
usually good and cover lightly with sifted soil or white sand. Place
the trays in the shade and keep moist. Germination takes about a
month, with the young seedlings grow very slowly in the beginning.
Prick out the seedlings as soon as they are large enough to handle
and grown on in bags until they are big and strong before planting
out into the garden.
Strong tip cuttings are best taken in spring ans summer when they
are less inclined to rot. The young plants respond well to fertilizer
feeding and by pinching the tips, the plants are encouraged to grow
bushier. Lobelia valida prefers a slightly alkaline soil.
Author: Liesl van der Walt