1. YOHANANTH SIVANANTHAN

2.  Clove, Syzygium aromaticum, is a monoecious (both male and female
flowers on the same plant) evergreen tree in the family Myrtaceae grown
for its aromatic flowers.
 The many branches of the tree are semi-erect with smooth oval shaped
leaves.
 The branches end with a 3–4 flowers near the tip with one terminal
flower and the others opening below it.
 The leaves, flowers and bark all have a distinct smell.
 The clove is the unopened flower buds.
 The tree grows 8–15 m (26–50 ft) tall and can live to be more than 100
years old.
 The clove tree may also be referred to as tropical myrtle and are native
to the Molucca Islands.

3.  Clove is mainly grown in Mid Country wet zone of Sri
Lanka.
 Kandy, Kegalle and Matale districts are major growing
areas
 The clove tree is a small evergreen tree that grows to a
height of 12-20 metres.
Clove Tree

4.  It thrives in coastal regions with temperatures between 15
and 30oC,average rainfall and a distinctive dry season(the
optimum level of rainfall is 1750 to 2500mm a year).
 It is a low altitude plant that grows best at altitudes lower
than 300m above sea level although it will also grow at
altitudes above 900m.
 The young leaves of the clove tree are bright pink and
change to a greenish yellow as they mature.
 The flowers develop in cluster of three to ten groups,each
will three flowers per group.
 These flowers are dried and grinded to use for cooking.
 Euglenol is responsible for that distinct aroma and taste
that the cloves have.
 Eugenol is a phenyl propene,an allyl chain-substituted
guaiacol,
 Eugenol is a member of the phenylpropanoids class of
chemical compounds. It is a clear to pale yellow oily
liquid extracted from certain essential oils especially from
clove oil,nutmeg,cinnomon basil and bay leaf..
 It is slightly soluble in water and soluble in organic
solvents.

5. Clove tree Clove buds
Clove foliage Clove fruit

6. Clove flower
Dried Clove
Clove fruits in tree

9.  Soils and Climatic need
Soil
Clove thrives well in a variety of soils.
Deep and rich loams with high humus content are best suited for the crop.
It also grows satisfactorily on laterite soils.
Pure sandy soil is unsuitable for this crop. Clove does not tolerate water logging and
therefore land selected for this crop should be well drained.
Climate
Clove grows well in a humid tropical climate from sea level up to 1000m elevation.
An average rainfall of 1750- 2500mm,per annum is sufficient. It is however,
necessary that dry periods alternate with moist ones for good flowering.The annual
average temperature should be 20 o - 30o C without much seasonal and diurnal
variation.Persistent strong winds are harmful.
Shade is essential during the first two or three years of growth. Thereafter full
exposure to light is beneficial.
 Crop Establishment
planting material
Clove is propagated through seeds. Tree ripe fruits should be sown immediately
since the viability of seeds is rapidly lost within 48 hours of collection.
Seeds obtained by removing outer pulp show early and uniform sprouting. The seeds
are sown in perforated polythene bags consist of equal parts of well decomposed
farm yard manure, top soil and coarse sand. The size of the polythene bags may
vary from 10 Χ 20cm to 25 Χ 40cm depending on the time kept in nurseries before
field planting. Bigger plants (15-20 months) establish better in the field.

10.  Field planting
Spacing: 20’Χ20’(250 plants/ha)
Temporary shade for 2-3 years is necessary.
Artificial shade for newly established plants may
be required during sunny seasons. Whenever
possible ground cover crops such as leguminous
sps, which do not compete with clove, should be
established as a soil conservation measure.
 Propagation
Clove is commercially propagated from seeds
which are planted soon after harvest.
Seeds should be collected and extracted from
the fruits of healthy mother plants exhibiting
desirable characteristics.
The seeds are extracted by soaking the fruits in
water and peeling the skin from the fruit.
The seeds can be planted in prepared nursery
beds or polyethylene bags containing a mixture
of soil and aged manure and should be planted to
a depth of 2 to 5 cm (0.8-2.0 in) and spaced 12
to 15 cm (4.7-5.9 in) apart.
Germination usually occurs within 1 to 6 weeks.
The seedlings should be shaded to protect them
from harsh sunlight. The seedlings should be kept
moist through regular watering and can be
transplanted when they reach at least 30 cm
(11.8 in) in height. The seedlings should be
hardened off by exposing them to increasing
amounts of sunlight before the are transplanted
to the field.
Clove nursery

11.  Crop management
fertilizer application
Recommended mixture - 625 kg / ha at the 10th year
and after (density 250 plants/ha)
 Crop protection
Diseases
No serious diseases and pests have been reported in
Sri Lanka
Pests
No serious pest and diseases have been reported in
Sri Lanka except wilting of nursery plants in large
proportions. The incidence of wilting can be
controlled by controlling shade and water
application. Leaf spotting due to Pestalots sp.
and Collectotrichum sp is fairly common in nurseries
and during wet weather, but do not seem to have any
serious effects.

12.  Dieback (Eucalyptus canker) Cryphonectria cubensis
Symptoms- Once fungus enters a wound on a branch it moves downward until it
reaches the branch junction; all branches above the junction die back
cause – Fungus
Comments - Fungus attacks wounded areas of the plant
Management - Avoid causing damage to trees with machinery and tools; protect
pruning wounds with appropriate fungicide; infected parts of trees should be pruned
out and burned; any resultant wounds should be treated with fungicide paste
 Nematodes (Ring nematode, Reniform nematode, Common spiral nematode)
Criconemoides spp. Rotylenchulus reniformis Helicotylenchus dihystera
Symptoms - Dark lesions on roots; stunted plant growth; yellow leaves; slow
growth and low yield
Cause – Nematode
Commen - Damage from nematodes often promotes root infection by bacteria
and fungi
Management - Solarizing soil can reduce nematode populations in the soil and
levels of inoculum of many other pathogens

13.  Coconut scale Aspidiotus destructor
Symptoms - Pale yellow spots on leaves; entire leaves yellowing; leaves turning brown and
dropping prematurely; adult insect is a flattened oval, resembling a scale, which is red-brown
in color
Cause – Insect
Comments - Insect also attacks other crops such as coconut, tea and mango
Management - May be possible to control coconut scale by pruning infested parts of trees and
destroying by burning; chemical control may be necessary
 Oriental fruit fly Bactrocera dorsalis
Symptoms - Dark brown to black lesions on foliage; adult insect is a small fly with a bright
yellow abdomen with a distinctive dark "T-shape" pattern; larvae are cream-white maggots
which burrow into fruit
Cause – Insect
Comments - Oriental fruit flies are serious pests of many crops including mango, avocado,
guava, pineapple and papaya
Management - One of the most effective methods of controlling the oriental fruit fly on many
crops is to bag the fruit in paper bags or polythene sleeves to prevent oviposition by female
flies; chemical sprays are most effective when combined with a protein bait to attract the
insect
 Soft scale Ceroplastes floridensis
Symptoms - Reduction in plant vigor and viability; wilting leaves with abnormal coloration;
stick residue on leaves; insect is a a rounded scale covered in white or pink-white waxy
substance
Cause – Insect
Comments - Large populations of soft scale promote the development of sooty mold
Management - Natural enemies of the soft scale can generally provide good control of the
pest; application of horticultural oil may be applied if scales become problematic; healthy
plants are less susceptible to scale damage than those which are stressed so adequate
irrigation and fertilization are important in scale management

14.  Sumatra disease Ralstonia syzygii
Symptoms - Dieback of trees which begins in the crown and leads to
tree death within 3 years of initial infection; leaves turn chlorotic and
drop from the tree or may wilt and remain attached; discoloration of
vascular tissues evident as gray-brown streaks in new wood; bacterial
exudate may ooze out of tissue when cut
Cause – Bacterium
Comments - Bacteria are limited to the water-carrying vessels in the
tree (xylem); the disease is thought to be transmitted by Hindola
striata and Hindola fulva, both sucking insect species
Management - An antibiotic - oxytetracycline - can be injected into
the tree to slow the decline of infected trees but there is currently no
known cure for the disease; several insecticides can give control
of Hindola insect species which are believed to spread the disease

15.  Clove must be dried before they are stored and
sold for market.This brief outlines the important
steps that should be taken pre-harvest and post-
harvest to ensure that the dried cloves are of
top quality for the market.
 Harvesting
 Pretreatment
 Winnowing
 Grinding
 Packaging
 Storage

17.  Cloves trees are first harvested when the tree is
6-8 years old.
 The timing of harvest of the clove buds is
critical.
 The buds should be harvested before the purple
or crimson flowers start to develop.
 The correct time of harvest is when the outer
green leaves of the flower bud change from olive
green to yellow pink and before the petals fall
to expose the stamens.
 Clusters of flower buds are hand picked from the
branches.It is important that the branches are
not removed or damaged as this will reduce the
yield of future crops. .
 The harvesting season commences usually in
December and extends up to the end of April
depending upon the locality.
 The average yield of dry cloves in Sri Lanka is
about 250kg/ha.Under good management
conditions a yield of abut 850kg/ha can be
obtained

18.  harvest the buds are detached from the stalks by holding a
cluster in one hand,pressing it against the palm of the other hand
and slowly twisting so that the buds fall off.
 The hands of the processor and the room in which the buds are
separated must be very clean to prevent contamination of the
cloves.
 The stems and buds are separated and dried separately.The
stems can be used for oil distillation.

19.  The buds have to be dried quickly or
they will start to ferment.
They are usually dried in the sun,spread
on clean mats.The cloves should be
raked and turned frequently to ensure
they develop an even brown colour.
The colour of buds changes from pale
russet to a darker brown as the clove
dries.The drying process takes about
four or five days.It cannot be speeded up
or the cloves will become dry,brittle and
withered rather than plump.
 The final moisture content of the dried
cloves should be 8-10%.Experienced
clove dries will know when the cloves
are fully dry as the buds will snap
easily.during the rainy season,cloves
should be dried using a mechanical drier
such as a tray drier.
badly dried cloves are pale brown and
classified as khuker.

20.  Winnowing
The dried buds are winnowed using a
traditional winnowing basket to remove
dust and other foreign matter.Small
cleaning machines are available that use
a blower to remove the dirt and dust.
 Grinding
Grinding can be a method of adding
value to a product.
However,it is not advisable to grind
spices.
After grinding,spices are more
vulnerable to spoilage.The flavor and
aroma compounds are not stable and will
quickly disappear from ground
products.The storage life of ground
spices is much less than for the whole
spices.It is very difficult for the
consumer to judge the quality of a
ground spice.It is also very easy for
unscrupulous processors to contaminate
the ground spice by adding other
material.Therefore most consumers,from
wholesalers to individual
customers,prefer to buy whole
spices.Dried cloves are usually sold
whole.

21.  Cloves can be packaged in
polythene bags of various sizes
according to the market demand.
 The bags should be sealed to
prevent moisture entering.
 Sealing machines can be used to
seal the bags.Attractive labels
should be applied to the products.
 The label needs to contain all
relevant product and legal
information the name of the
product,brand name,details of the
manufacturer,date of the
manufacture,expiry date,weight of
the contents,added ingredients
plus any other information that the
country of origin and of import may
require

22.  Dried cloves must be stored in moisture proof
containers away from direct sunlight.
 It is essential that the cloves are fully dry before they
are stored.Any moisture within the bags will cause
the cloves to rot.
 The stored cloves should be inspected regularly for
signs of spoilage or moisture.
 If they have absorbed moisture,they should be re
dried to a moisture content of 10%
 The storage room should be clean,dry,cool and free
from pests.
 Mosquito netting should be fitted on the windows to
prevent pests and insects from entering the room.
 Storing smelling foods,detergents and paints should
not be stored in the same room as they will spoil the
aroma and flavor of the cloves.

23.  Seed propagation is commercially practiced in
clove.
 Seeds are collected from selected ripe fruits of
the ‘mother tree’ and then they are soaked
overnight before sowing them in the nursery
beds.
 Seed pericarp is removed before sowing.
 It is advisable to sow the seeds immediately
after harvesting.
 Another propagation method adopted for
commercial cultivation of cloves is ‘approach
grafting’.
 Approach grafting of clove on its own rootstock
is successful