Eulophia petersii
Zulu. isaha
Note that the sepals and petals are spirally coiled with
the tip innermost
Eulophia petersii is a terrestrial orchid belonging
to the plant family Orchidaceae. It is found in amongst rocks in thickets in hot dry arid to very
arid environments from the Arabian peninsular in the north down the eastern
coast of Africa southwards as far as the Limpopo, Mpumalanga and KwaZulu-Natal
provinces of South Africa.
Eulophia petersii is an unusual member of the orchid
family in that it lives in a harsh environment. Where it has adapted to very
arid environments and is among the few orchids genus’s to have evolved a
truly desert living species
It is often found growing in acidic sandy soils or in
rock outcroppings often in acid soil derived from decaying granite.
Eulophia petersii has many growth forms even within close
proximity to one another.
Below I have shown two specimens that are growing next to
one another in the sale growing medium one with medium length leaves and pseudo
bulbs the other with extremely long leaves and long thin pseudo bulbs.
The leaves of Eulophia petersii are thick, fleshy and
very fibrous and have a sharp serrated edge that vary considerably in length
from short and broad to very long and narrow.
There are usually two to five leaves per pseudo
bulb.
Eulophia petersii from the Weenen area with medium length
leaves
The pseudo bulbs
are green to yellowish with pronounced ribbing being almost smooth when fully
engorged with water and highly ribbed when very dry the vary in length
considerably.
Eulophia petersii from the Mapumulo area with extremely
long leaves and long thin pseudo bulbs
The form that grows in Yemen on the southern tip of
the Arabian peninsular is much smaller and more compact in habit.
The numerous flowers are widely spaced on a branched
inflorescence that can be up to over 2 meters in length. The flowers are green
with reddish brown markings with a wrinkled white lip with pink markings. There
is quite a bit of variability in the colouration of flowers between plants.
Often the sepals and petals are circinate, that is spirally coiled with the tip
innermost as in the photo above.
Eulophia petersii showing an extensive healthy root system
supporting a healthy plant
Eulophia petersii plants consist of clusters of
squat, fat green to yellowish stems called pseudo bulbs connected by short
rhizomes that bear a small number of succulent, sharp-edged leaves. The plants
are evergreen and the leaves can persist for several years, but the actual
growth of the plants is highly seasonal.
New pseudo bulbs and foliage are produced in spring and
summer, and tall racemes of flowers are produced in mid-summer.
In the winter, the plants are dormant and can withstand
long periods without water.
Traditional uses
Eulophia petersii is used as a love charm
Growing Eulophia petersii
Eulophia petersii are very easy and rewarding plants to
grow provided one follows a few simple rules. They are probably best grown
indoors as pot plants in most localities that have high rainfall or very low
temperatures. Eulophia petersii are very hardy and take very little time to
care for and to produce good results making them an idea pot plant.
My own plants are grown in a mixture of coarse gravel
derived from decaying granite, crushed brick, and clean river sand to which I
add a small amount of well rotted leaf mould. They also do well in general
purpose cactus and succulent mixes.
I grow my plants on a hot north facing windowsill indoors where they get
plenty of sun so that I can protect them from the rain and the yellow orchid
beetle Lema pectoralis which is a major pest which can badly damage a plant in
the blink of an eyelid.
I do not over pot my plants but I do ensure they have
enough space to develop a very good extensive root system this essential for
good results.
Yellow orchid beetle Lema pectoralis
In summer I only water my plants when the growing medium
has completely dried out for a week or so and I see that the pseudo bulbs have
wilted a little then I completely soak the plants with water to which I have
added a little liquid fertilizer. Never add more fertilizer per litre than the
manufacturers recommendations, this has produced very good results for me. At
least once a year in the summer I take the plants outdoors and soak them
heavily with a hose pipe to flush any accumulated salts out of the growing
medium. This can also be done indoors in a bathtub or basin.
In winter I keep my Eulophia petersii very dry I only
water them when I see that the pseudo bulbs have shrunk considerably and
the two halves of the leaves have started to fold together and then only enough
to slightly wet the growing medium, after a day or two I add a little more
water until the pseudo bulbs have regained not more than 50% of their full
size. This ensures that the plants develop a very large and healthy root system
as can be see in the accompanying photograph. I do not soak the plants.
In the spring when new growths appear I slowly increase
the amount of water given until the new pseudo bulbs are well developed
Eulophia petersii do not do at all if well if they over
watered in particular in winter and do not develop and maintain a good root
system. The easiest way to check if your plant is being over watered or not is
to gently tip it out of its growing container and to inspect the roots. A
healthy well cared for plant will have and abundance healthy white roots with
white tips while in active growth with no black marks or rot on them.
Eulophia petersii can be grown outside in the garden if
grown in well drained soil and if they can be protected from mole rats and the
yellow orchid beetle. When grown outdoors the must be grown in a hot sunny
position or the new growths will tend to rot in the rainy season in places such
as Durban and the natal coast.
Eulophia petersii has all the attributes of an excellent
green roof plant and will no doubt make a very good green roof plant in areas
with a suitable climate. I an yet to test Eulophia petersii under the
conditions I experience at Mount Moreland but I am confident they will do well
as I already have four species of Eulophia that grow under direr conditions
that are thriving with no care whatsoever on my own roofs.
Eulophia petersii can easily be propagated by
subdivision, which is probably best done at the end of winter when the first
growth is noticed, just be careful not to damage the new growth.
Eulophia petersii plants set seed if pollinated, but as
with most other orchids the seeds can mostly only successful grown in flasks on
a special growing medium under sterile conditions.
I have never tried growing Eulophia petersii seeds in
soil as I have successfully done with Eulophia speciosa but with a little
experimenting under the correct conditions it is no doubt possible.
Michael Hickman
Landscape Design and Rehabilitation Specialist
25.19.14
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So helpful! Do you know what minimum temperature these plants will withstand if grown outside?
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