Sisal is a species of Agave native to southern Mexico and widely cultivated And naturalised in many other countries. It yields a stiff fibre that is used in making various products. In the past, several species of Agave were used for fiber production, but presently A. sisalana is commercially grown species.
The botanical name of the sisal plant is Agave sisalana and the genus Agave L. of the Agavaceae family, which contains about 300 species.
Sisal was originally grown in southern Mexico but widely cultivated and naturalised in many other countries. It has been widely introduced in the tropics and subtropics, in India between 1885 and 1892, in Tanzania in 1893,
in Brazil at the end of 19th Century, and in Kenya between 1903 and 1908. The first commercial plantings in Brazil were made in the late 1930s and the first sisal fibre exports from there were made in 1948.
HOW TO PRODUCE SISAL?
Cultivars
There are many varieties of the Agave plant throughout the tropical and subtropical world, especially in the Central American region, but the most
important variety for fifi bre production on a commercial basis are A. sisalana and its hybrids, the most common of which i s known as Hybrid no.11648 and A. fourcroydes (known as henequen)
Description
Mature Plant
Sisal is a tall perennial monocotyledon. It is a rela tively smooth, straight and subtly yellow fibre. Sisal is a hardy plant that can grow well fast all year round and attains a height of only 15,2 cm in 9 months after planting and 0.6 m at the end of 2 years. The plant grows for 7 to 12 years producing from 120 to 180 leaves depending on location, altitude, level of rainfall and variety of plant.
STEMS
Two to three years after transplanting, a 20 cm tall stem is formed, which will reach a height of about 1,2 m when flfl owering. White, flfl eshy stems develop from underground buds at the base of the plant, fifi rst growing sideways and then upwards to form new plants. These new plants are known as suckers.
ROOTS
The sisal plant has a shallow, fifi brous root system that is a maximum of 60 cm deep. The 2 to 4 mm thick root arise from leaf scars at the base of the bole beneath the soil surface and extends horizontally up to 5 m away from the mother plant and form suckers, which can be used for propagation.
LEAVES
The plant has stiff, heavy, persistent leaves that are 0,6 to 1,2 m long, 10,2
to 20,3 cm wide, and 2,5 to 10,2 cm thick when matured. The leaves are
spirally arranged around the trunk, greyish-green in colour and covered by a layer of wax. The leaves of the plant contain coarse, cream-coloured or pale yellow fifi bres of 3 %.
FLOWERS
The sisal plant flfl owers only once and that are at an age of about 12 years. Before flowering, a flower stalk of 4,5 to 6,0 m develops from the growth point. The flfl ower stalk subdivides to form branches that bear the flfl owers. The flfl owers do not produce seed, but form bulbils, which are
used for reproduction.
TRUNK
The base of the plant consists of a short trunk of about 30 cm x 150 cm. The leaves are spirally arranged around the trunk. The growth point from where the leaves develop, and eventually the flower stalk, is situated on top of the truck
Essential part
The main components of the plant are the leaf, the trunk and the rhizome.
The leaf yields the sisal fifi bre and a pulpy waste. The fifi bre is by far the most important product of the sisal plant. Pulp waste constitutes about 12% of the sisal leaf. The trunk and rhizome yield various wood and chemical products at the end of their productive life
Climatic requirements
Temperature
Sisal grows best in subtropical climates. The plant grows well in hot climate
with temperatures between 10 to 32 °C. The maximum temperature should
be 30 to 40 °C, with minimum temperatures of 5 °C.
Rainfall Requirements
Rainfall plays an important role as far as fifi bre production is concerned. The plants are not frost tolerant and produce the best in areas with an annual rainfall of 500 mm and higher. An annual rainfall average of between 600 to 1500 mm is required. Sisal can also grow in areas with less or erratic rainfall.
In high-rainfall areas, production may become problematic due to weed
infestation and occurrence of diseases. Waterlogging causes stunted growth.
Soil requirements
The plant is not soil specific, but it grows best in well-drained loamy soil.
Sisal can be cultivated in most soil types except clay and has low tolerance
to very moist and saline soil conditions. Soil pH of between 4.0 and 6.0 is
important.
Propagation
Sisal is propagated vegetatively with bulbils or suckers. Suckers: These are produced close to the parent and develop from axillary buds situated on the bole of the parent plant. Suckers are produced throughout the plant’s life and may be removed and planted directly into the field. Bulbils: When the sisal plant reaches maturity it produces a pole or flower head and then senesces. In the axillary buds on the pole a large number of bulbils are produced. Bulbils are preferred as planting material as they are homogenous and produce vigorous plants. The bulbils are planted out in nurseries and subsequently transplanted into the field. The grower prefers this method because it enables him/her to maintain pure lines.
Soil preparation
In preparing the land, soil samples should be taken and analyzed. Land
should be well prepared before planting by ploughing to a depth of not less
than 30 cm; a ripper should preferably be used first, followed by an ordinary ploughing to a depth of 23 cm. The existing vegetation must be destroyed and the sisal plants are then planted in the hole in the ground.
Field layout and design
The recommended planting patterns are a series of double rows of 60 cm
apart with a 2.5 m alley between a pair of rows.
Planting
For planting sisal, the bulbils must be established in a nursery first. They are planted in beds at 10 cm x 10 cm apart where they g r o w f o r s i x m o n t h s . Application of sisal waste in the nursery is beneficial to plant growth. After that they go to secondary beds where they are placed 30 cm x 30 cm apart. After 12 to 18 months the plants are ready to be planted out into the field. Distance between rows should be 1,0 to 1,5 m and 4,0 m. The planting depth should be 3 cm. At transplanting the fibrous roots around the base of the plantlets are usually cut off and the lower leaves may be pulled off. Transplanting of sisal into the field can be done any time of the year as it is a succulent with good drought resistance. Usually it is done before the
beginning of the rainy season when the land is still dry because this will limit disease infection and weevil attacks. Transplanting is done by hand. Planting holes are made by hoe and soil insecticide is applied into the soil. Although roots can be removed during transplanting, care should be taken not to damage the boles. Suckers may be established directly. Before planting in the field, the soil is cleared mechanically or by hand and it may be ploughed shallowly. If the rainfall is above 700 mm, plant at 1 m by 750 mm, between 500 and 700 mm at a square metre and 300 to 500 mm or alternately 1,5 m and 1 m by 1 m. The planting depth should be 5 to 8 cm.
Fertilization
Sisal is an environmentally friendly fibre and almost no fertilisers are used in its cultivation. Where sisal is established on new land fertilisation is generally unnecessary, but where it is established on an old land, fertiliser is usually needed. It also recommended that, after the leaf has been decorticated, the waste material should be ploughed back. Where pH is below 6,0 lime should be applied. Urea, lime-ammonium nitrate (LAN) and superphosphate are some of the chemical nutrients that are used for sisal fertilisation
Irrigation
Growing sisal does not require irrigation, as the sisal plant is drought
resistant and cultivated as a rainfed crop. However, the processing of sisal
leaves is very water intensive and on average 100 m3 of water is used to
produce one ton of fibre.
Weed control
Weed control is of primary importance during the first two years. Weeds
should be controlled in the first 2 to 3 years after transplanting: by hand, or by mechanical or chemical means. Common weeds in sisal plantations
include: couch grass (Cynodon dactylon (L.) Pers.), nut grass (Cyperus
spp.), African couch (Digitaria abyssinica (Hochst. ex A. Rich.) Stapf),
Lalang (Imperata cylindrica (L.) P.Beauv.), cow-itch (Mucuna pruriens (L.)
DC.) and Guinea grass (Panicum maximum Jacq.). After 2 to 3 years, weeds
may be allowed to grow during the rains and cut down at the beginning of the dry season to conserve moisture and provide mulch. It is recommended that cover crops should be grown between the rows during the fifi rst three years after establishment in order to keep the land free
from weeds. Once sisal is mature a medium weed cover is not harmful.
Weed control is normally carried out by hand-hoeing when the crop is young and mowing or slashing when the crop is large enough to cut. Under highrainfall conditions, more cultivation should be done annually.
Pest control
Sisal is relatively free from pests and diseases, though the only serious
insect pest of sisal is the agave weevil or Mexican sisal weevil (Scyphophorus acupunctatus. Synonym: Scyphophorus interstitialis). Sisal is an
environmentally friendly fibre and almost no pesticides are used in its
cultivation, because it is resilient to disease. Some common pests and
diseases are:
Sisal weevil (Scyphophorus interstitialis)
DAMAGE
Weevil damage to sisal plants is either done by the adult or the larva. The
larvae damage the subterranean parts of young plants and may cause
substantial losses.
SYMPTOMS
The presence of brownish-grey speckled patches, usually elliptical or rounded and infested plant grows slowly. The grub (larva stage) bores into the young plant’s bole, making a tunnel. Rotting follows and the plant dies.
The adult weevil feeds at the axils of the upper most leaves, adjacent to the
growing spike leading to staining of the fifi bre.
CONTROL
• Cultural control: use of non-infected planting materials, removal of dead
boles and avoiding contaminated fifi elds (sanitation measures).
• Use of guard rows supported by placing split boles whose cut surfaces
are dusted with insecticides to reduce infestation.
• Chemical control: The application of registered insecticides.
• Biological control by sisal weevil’s natural enemies, e.g. predators such
as Placodes ebeninus Lewis; the beetle that feeds on the living larvae in
rotten sisal boles.
• Planting before or in the early rains and the application of registered/
recommended pesticides in the soil around young plants can control the
pest.
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