So you want to be a durian grower!
A durian orchard
Ok, let's look at what you're getting into.
Did you know that...
- it takes 5-6 years (sometimes longer) before you can harvest your first fruits;
- it is not uncommon to see matured durian trees fail to flower, or to set fruit during fruiting season;
- developing fruits on the tree may drop prematurely, or become misshapened and unmarketable;
- many insect and mammalian pests attack durian and some may cause serious damage to the tree;
- many fungal diseases attack all parts of the tree including ripen fruits on sale, and some diseases are fatal;
- durian fruits may also suffer from physiological disorders such as "uneven fruit ripening", "wet core" and "tip burn" which make them unmarketable;
- "two-legged" thieves can smell your ripening durian fruits miles away and steal them if you are not vigilant
- natural calamities such as drought, fire or too much rain may happen and destroy your trees;
- when you have a bumper harvest, so can other farmers - a glut in the market brings down prices, therefore less profits; and
- marketing the fruits can be a bigger challenge than just producing the fruits.
Success of a durian orchard starts with:
1. Agro-ecological regions
Many countries have maps showing agro-ecological regions where the effects of climate and soils on agricultural production of certain crops are generalized and recommendations for the most suitable crop or crops are given (See Page on Soils, Climate, and Map of Durian Production areas). If your site falls within the boundaries recommended for durian then you can be reasonably sure that your durian trees will produce satisfactory results.
Just take a good look around your site. If there are durian trees growing and producing fruits, then you're okay. However, be aware that small hills or depressions, water bodies and natural vegetation may affect the suitability of an area for a particular crop. Rainfall, for example, may varies strongly from year to year. Sometimes you may have to adapt the crop to prevailing conditions, by changing production methods (planting distance, pruning and training, etc.), selection of new cultivars or improving soils and landforms (fertilization, drainage, irrigation, terracing, etc.) so that climatic disadvantages are neutralized or minimized.
2. Site Location
One important consideration is the location of your site. Access to your farm should be convenient not only for you to visit your farm on a regular basis but for marketing your durian fruits when they come into production. Durian are climacteric fruits, they keep on ripening after harvesting until they spoil in about a week. Harvested fruits must be marketed and consumed within 2 to 3 days. Logistics is very important as durian fruits crack and spoil easily during transportation.
3. Land Title
Different countries have different laws regarding agricultural land and specific crops. In Malaysia, the land title lists the types of crops that can be planted. If your farm is listed as "dusun" (Malay for orchard) then you can plant any fruit trees suited for the tropics.
However, if the specified crop listed is rubber, for example, then this has to be changed to orchard before you can plant durian legally in the site. Before clearing the old rubber trees, don't forget to apply for replanting subsidy from RISDA (Malaysia's Rubber Industry Small-holders Development Authority). This comes in the form of cash and/or in kind such as fertilizers and planting materials.
4. Land Preparation
The most suitable method of preparing your land for durian planting depends very much on your farm size, topography and planting system. Large and fairly flat land uses big machinery to quickly clear big trees and thick undergrowth. The disadvantage is that heavy machinery compacts the soil which need to be ploughed up again before planting the young durian trees.
Small farms and hilly land usually rely on chain saws, axes and slashing knives like machete or parang to clear the unwanted vegetation. Tree trunks or stumps are generally left to rot but if they are diseased or termites-infested, appropriate action must be taken to prevent its spread.
Dried branches and trunks are usually collected into small piles and burnt. Big open fires are illegal and should be avoided as they not only pollute the environment but scorch the soil. Usually some action must be done to prevent soil erosion after clearing the land. Planting cover crops is the best option.
5. Legume Cover Crops
Legume cover crops
Durian farmers often grow cover crops to prevent soil erosion, to improve or maintain the soil structure and fertility especially soil nitrogen, to suppress other noxious weeds, to prevent rapid loss of water from the soil through evaporation, and to keep the soil temperature down during hot weather.
Leguminous plants are usually used as they are easy to establish. They are seldom used as green manure but as a living mulch. Cover crops are usually seeded just after land clearing and at the on-set of the rainy season. They grow rapidly and cover the entire area of the farm within two years. The popular legumes are Pueraria phaseoloides, Calopogonium mucunoides, Centrosema pubescens and Mucuna bracteata (See Page Legume Cover Crops for more information).
The common practice is to use an equal amount of Pueraria phaseoloides, Calopogonium mucunoides and Centrosema pubescens at the rate of 3 - 5 kg/ha. In Malaysia, Mucuna bracteata has been successfully used by RISDA for oil palm replanting on peaty soil.
Cover crop seeds or planting materials must be of high quality and free from pathogens to avoid failure through low quality seeds. Usually some seed treatment is required to break the seed dormancy
6. Irrigation system.
An efficient irrigation system is a must if you intend to practise intensive management methods such as planting durian trees closer together and establishing smaller size trees for early fruit bearing and to facilitate field practices such as spraying chemicals, pruning, flower and fruit thinning, harvesting etc. Water is very critical during planting in the field as young durian trees are very susceptible to drought and mortality can be as high as 50%. Insufficient water can also weaken the plants and predisposes them to pests and diseases.
Water is also very crucial especially during flowering and fruit development stages to achieve good and quality yields. Many farmers use the irrigation system not only to supply water but to deliver plant nutrients, supplements and chemicals directly to the durian trees. A stream with a regular flow of water even in the dry months or a well with high water table are excellent features for a durian orchard.
Operating a durian orchard without irrigation facilities is a very risky venture. Rainfall can varies greatly from year to year and from month to month. The dry months that occur in-between the monsoons play a critical role in durian production.
A period of 3 to 4 weeks dry weather is needed to stimulate flowering. It takes about one month for a durian flower to develop from first appearance as a tiny bud to an open blossom. Water is important to promote growth and development of the flower buds, blooming, fruit set, fruit growth and maturity.
To rely entirely on available moisture in the soil and rainfall is perilous. If the weather is too dry and hot, the flowers will shriveled, and fruit development hindered. On the other hand, too much rain and high relative humidity cause poor fruit set. The best option is to have an efficient irrigation system to manage water properly during the durian reproductive stage to achieve high yields of good quality fruits.
A durian orchard without irrigation is like growing durian the traditional way. Any improvement in durian production can only come from how well you adapt the durian trees to suit the natural environment and its dynamic conditions. Some of the options that you can use are: plant drought tolerant clones or cultivars, use advanced planting materials, adopt wider planting system, practise harder pruning, ensure proper fertilizers placement and timing, and practise integrated pests, diseases and weeds control. However, the durian trees will be much bigger and taller than their irrigated counter-parts. They will also take a longer period to mature and to start bearing, and the yields much lower.
Setting up a proper irrigation system is expensive but it's a good long-term investment if you are really serious in getting the best from your durian trees. Many successful farmers used second-hand diesel engines from trucks or lorries, some modifications and low cost to run their water-pumps. They can be as powerful and efficient as new ones.
PVC pipes should be buried in the ground to prevent rodents from chewing into them. Unburied pipes are usually hidden from sight by overgrown weeds or other vegetation thus making them easily damaged by moving vehicles or farm machinery especially grass-cutters. Fire can also burn and destroy PVC pipes lying unprotected on the ground.
It's a good practice to set up the irrigation system first as it is very difficult to lay out the heavy and rigid PVC pipes without causing damage to young durian trees which are already planted in the field.
7. A Good Mix of Durian Clones or Cultivars
Growing durian trees from seeds is obsolete. Durian farmers can now choose to grow and manage specific durian clones or cultivars based on their own needs and goals.
The most important rule to remember is that never plant a single durian clone or cultivar in an orchard. Since all plants in a clone have the same genetic make-up, a new disease or disorder that breaks down the genetic defenses will affect the entire clone. This will wipe out your durian orchard and all your efforts will be wasted.
To minimize this risk, the best approach to establish a durian orchard is to plant a good mix of durian clones or cultivars. Planting a few clones together also helps in cross-pollination and fruit set, thus increasing fruit yield and quality. Another advantage is that clones with different maturity indices can stretch the durian fruit season over several weeks.
Let's take clone D197 or Musang King for an example.
D197 or Musang King
Presently, it is the most popular clone in Malaysia and Singapore. D197 fruits fetch the highest price in the market and is in high demand. There are lots of information on the D197 fruit such as shape, colour, taste, size etc.
But, information on the D197 tree characteristics such as tree vigour, productivity, disease tolerance, etc. is generally lacking. Did you know that D197 is very susceptible to Leaf Spot disease caused by Rhizoctonia solani?
Hot and high humidity favors high incidence of leaf spot disease
Though Leaf Spot or Rhizoctonia disease is relatively easy to control with the proper management practices, there are a host of diseases such as Phytophthora and many others to be wary of.
Therefore, it is very risky to plant only D197 in an orchard unless you have total information on that particular clone or cultivar. The local growing conditions, such as climate and soils, as well as management practices can greatly influence the tree characteristics and its performance. D197 may do very well in a certain area but can be a total failure in others.
D197 is NOT in the list of durian clones recommended for commercial planting by the Department of Agriculture.
The best approach is to gather as much information as you can, not on just one clone or cultivar but also on other clones or cultivars as well, and talk to as many local people as you can. You can get information from the local agricultural officers, other durian growers in your area, the nurserymen, fertilizers and agricultural chemical suppliers, farm tools suppliers, the fruit buyers etc. Do not forget your immediate farm neighbours for they may have lots of good and/or bad experiences with durian planting.
In Malaysia, the Department of Agriculture recommended 3 clones for commercial planting in specific agroclimatic zones. They are D24, D99 (Gob kecil) and D123 (Chanee).
Another 4 clones; D145 (Beserah), D158 (Gan Yau), D159 (Monthong), and D169 (Tok Litok) have interim recommendations for very specific areas.
MARDI has 3 durian hybrids - D188 (MDUR78), D189 (MDUR79) and D190 (MDUR88) which are high yielding and of good quality and be considered as good commercial clones.
Recommended durian clones of Malaysia
In Penang, popular clones planted are D163 (Hor Lor), D164 (Ang Bak), and D175 (Ang Hea).
In Selangor, D160 (Buluh Bawah), D162 (Tawa) and Penu (MDUR 505).
In Johore, D168 (Mas Hajah Hasnah).
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This recommendation had undergone extensive testing by MARDI.
Like many durian clones, D24 is self-incompatible, and when planted as the only clone in an orchard, will produce low yields and uneven fruit shape. D24 requires cross-pollination from other durian clones for better fruit set.
D24
Research shows that when D24 is planted in a clonal mix with clones such as D99 (Gob kecil), D98 and D114, the performance of D24 increases significantly in terms of yield and fruit quality. D24 has the best fruit quality, follow closely by D99 while D98 and D114 have acceptable quality.
D99 (Kop Kecil)
Another advantage of this clonal mix is that D99 can bear fruits during the off-season and thus is able to produce two crops a year. It is also an early-season clone with fruits ripening in 90-100 days from anthesis. D24 is classified as mid-season clone. Fruits drop from the tree 105-115 days after anthesis.
D98 and D114 are late-season clones with maturity index 120-130 days. This stretches the durian season to more than 3 weeks. Market prices are not affected as early and late-season fruits usually fetch higher prices because of the low production. Even though D24 matures during the peak in the durian fruit season where fruits are plentiful, it always fetches a good price because of its high quality.
Besides D24, three new hybid clones D188 (MDUR78), D189 (MDUR79) and D190 (MDUR88) have been recommended for clonal mix planting. They are all high-yielding mid-season clones with good quality fruits almost at par to D24.
MDUR hybrid durian clones
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Thailand uses a similar strategy where 4 major clones are planted according to maturity index; Gra-doom-tawng matures early to get the high market price, Chanee and Kanyao mature in mid-season and Monthong late season. This lenghtens the durian season, thus avoiding the risk of over-production to meet consumers demand, and maintaining good market prices throughout the season.
Artificial cross-pollination using Gra-doom-tawng as a pollinizer is strongly recommended for commercial durian cultivation in Thailand. Research has shown that when Gra-doom-tawng was used as pollen parent, fruit set percentage was significantly high in Monthong (27.2%), which is a leading cultivar in Thailand. High fruit set was also achieved in Chanee (16.3%) by Gra-doom-tawng pollen.
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In summary, the use of recommended durian clones or cultivars can help you intensify your orchard management to get higher yields, fewer unproductive years, more trees per hectare, higher maximum yield per hectare, much higher mean yield over the orchard's lifespan, more efficient management and lower cost of production.
However, some disadvantages are that the mother tree from where the cuttings or grafted materials are obtained may harbour diseases and pests that are then transferred to the new plants. Ensure planting materials are free from diseases and pests.
A cloned tree generally has a weaker root system than a seedling tree and therefore requires intensive management in keeping with its intensity of cropping.
Clonal trees are expensive and more plants are required for planting.
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