Grapes Production in the Philippines

A grape is the non-climacteric fruit, botanically a true berry, that grows on the perennial and deciduous  woody vines  of the genus  Vitis. Grapes can be eaten raw or used for making jam, juice, jelly, vinegar, drugs, wine, grape seed extracts, raisins, and grape seed oil. Grapes are also used in some kinds of confectionery.

Grapes are small round or oval berries that feature a semi-translucent flesh encased by a smooth skin.  Some contain edible seeds, while others are seedless. Like blueberries, grapes are covered by a protective, whitish bloom. Grapes that are eaten from the vine are called table grapes, as opposed to wine grapes (used in viniculture) or raisin grapes (used to make dried fruit).  Color, size, taste and physical characteristics differ amongst the varieties. Grapes come in a variety of colors including green, amber, red, blue-black, and purple. In general, whole grapes have a slightly crunchy texture and a dry, sweet and tart taste.

Grapes are excellent sources of manganese  and good sources of vitamin B6, thiamin (vitamin B1), potassium, and vitamin C. In addition, grapes contain flavonoids: phytochemicals that are antioxidant compounds.

Today, Grapes can be grown in the Philippines. This has been proven in Arevalo, Iloilo, La Union and Cebu (where they have been growing grapes since 1950). There are many varieties that we can grow here. Grapes like loose, deep soil  with a ph lower than 5, so the application of lime helps. It is also good to put decomposed leaves around the plant to conserve the soil moisture. Grapes like terrain that is somewhat sloping so as not to lodge water and hurt the roots.

Grapes need plenty of sunshine (not shade) and good circulation of air to avoid the onset of disease. Within ten (10) to 12 months after planting, grapes are ready for harvest. Harvest is done three times a year — September, December, and Summer. In the first year, a hectare of land planted to grapes can yield about 1,700 kilos per hectare. In the third and fourth years 10,000 kilos per hectare can be harvested. Grape is most productive from its third to eighth year.

Table grapes is suited to a local climate and has unlimited market. However, one should be financially prepared for its late pay-off period which is three years after initial planting. After five years, a farmer can earn a total of P221,000 per hectare.

Aside form the flesh fruit itself, grapes have various by- product such as raisins, grape wine, grape juice, jams and jellies. during the 1960s and 70s, the country average import of these goods was worth $802,900 every year. In 1985, the value of imports soared to $1.7 million or P34 million at the exchange rate of P20.40 to a dollar. This does not include flesh grapes brought in by air travelers.

Flesh grapes now sell for P50 to P60 per kilo for those locally produced, and P60 to P120 a kilo for imported ones.

Large grape plantation can be found in Cebu, Ilocos Region, South Cotabato, Zamboanga, and other regions in the Visayas and Mindanao.

How to grow Grapes

Adaptation

Grapes grow best in areas with warm and dry climate and where sufficient irrigation is available. Places frequently by typhoon and continuous rain are least suitable. Suitable regions for grape production are western parts of Luzon, Palawan, Mindoro, Panay and Negros Occidental. Growing conditions, however, vary depending on the variety.

Most commercial vineyards are below 1,000 feet in elevation, some almost at sea level. Select a site that is flat or gently rolling so that soil erosion is minimal.

Grapes is adapted to deep, friable, well-drained and fertile loam soil, and grow poorly in the sandy and heavy soil. For high- quality fruits, select areas with soil acidity of 5.5 to 6.5 (slight to medium acid). The choosing planting should have full exposure to sunlight and fresh air. With appropriate condition, one can plant three to four crops a year.

Variety

The Vitis Vinifera variety account for more than 90 percent of the world’s total grape production. It is also known as European or Californian grapes and is acceptable to light soil.

American grapes varieties such as Vitis Labrusca or “Concord” requires high soil fertility, adequate water supply and “shallow” soil. These adapt well to clay and heavy soil.

Varieties used as table grapes and premium quality dry table wines can grow in less fertile soil, while those grown for raisins and common wines need deep fertile soil. Varieties proven to be adapt to local condition are the White Malaga, Ribier, Cardinal and IAC 971-1 or the Brazilian hybrid.

TABLE GRAPE VARIETIES

Variety Maturity period Color Shape:

• White medium late green/yel- ellipsoid low-green
• Ribier medium late black round
• Cardinal early cherry red round
• Brazilian medium late green/yel- round hydrid low green
• These are seedy varieties but are excellent in flavor.

Planting

Grapes are propagated mainly through cuttings. Carefully inspect plant materials be sure they are free from virus-caused diseases. Select cuttings from mother vines that produced large quantities of high quality barriers. Avoid cutting from newly vines and choose cutting the size of an ordinary lead pencil with three or four well-develop buds.

Plant them in well-drained medium such as fine or coarse river sand and hollow them to grow roots. After a month, transfer to pots or to plastic bags.

In the absence of the mother vines, young rooted ones can be bought in plant nurseries. Estimate the number of vines needed for plantation by using the following formula:

A = Number of vines
d * d

Where:
A= area in square meters of plantation
d= Distance between plants in meters (2.5 * 3.5)

For small backyard gardens, simply dig out individuals holes for each vine, about one cubic meter, then fill it up with top soil mixed with animal manure.

For large-scale production, prepare land of the flowing and harrowing 2 to 3 times. Dig holes for each vines arranged in lines or distances of 3.5 meters between rows and 2.5 meters within rows. Mix 2 kg of 16-20-0 (nitrogen – phosphorus) and 500 g of 0-00-60 (potassium) with one cubic meter of soil to fill up each hole. Chicken manure can be also be used.

Remove the rooted vines from the potting containers making sure that the soil holding the vines are intact. Gently set the plant into each hole and cover with the fertilizer-soil mixture. Water them after planting and regularly thereafter. Fifty grams of 45-0-0 (nitrogen) can be dissolved in 2.3 liters of water and used to water the newly planted vines.

Vineyard Management

Provide the plants with trellises or any type of plant support such as the overhead arbor or balag. They should be shoulder-high from the ground and wide enough to allow the grower to prune, spray or harvest efficiently. Five strands of wire one foot apart should be strong across a main horizontal bar made from the basal section of bamboo. Construct them in such a way that they will be able to stand wind pressure and the weight of the vines and its fruits. Growing branches should have sufficient space in which to expand.

Trained the vines to grow straight up the trellis by trying them loosely to stakes or guide posts. Remove all site shoots or regularly until the main vine has reached the top of the trellis. In case the unwanted shoots have grown and toughened considerably, remove them with a sharp knife or pruning shears.

When the main vine has reached the top of the trellis, pinch off its growing tip. Allow two to four lateral (side) branches to grow while cutting off other side shoots. The lateral branches should be the topmost ones, trained or guided to grow and extend opposite one another. Tie these loosely to the trellis wires and never allow them to overlap with adjacent vines. Cut off the growing tips of these lateral branches when they grow to 1 1/2 cm to encourage the growth of sub-lateral shoots. Do this regularly until the sufficient number of fruiting canes have grown from the lateral branches .

Pruning, which involves cutting under-wanted section of branch including leaves, should be done to encourage flowering and fruiting. Determine the normal position, location and size the flower buds of the variety being used to estimate the appropriate spots for pruning. Do this when the vine has grown a full year and the canes (fruiting twigs) are brownish in color. Canes should have distinct normal buds and mature leaves. Prune only mature and slow-growing branches and using a sharp pruning shear about an inch above a bud.

For best results, fertilizer and irrigate the vines regularly two weeks before pruning. Pruning should be timed such that fruiting will not occur during the rainy season which could result in damaged fruits.

The kind of pruning done depends on the location of the fruit buds. Varieties with fruit buds near the base and those with thin canes are pruned after its fourth bud, while those with large-size canes and with fruit buds after the fifth node (bud) are pruned beyond its fifth bud.

New buds will sprout about two weeks after pruning. Table grape varieties grow flower cluster between the third and the seventh node of the new shoot. If flower cluster fails to appear beyond the seventh node, the shoots is unproductive.

The Thompson Seedless, White Malaga and Concord varieties responds well to cane pruning , while the Cardinal, Ribier, Flame Tokay and the British Hybrid respond well to spur-pruning.

When the fruits have emerged, remove flower or fruit clusters that hinder the growth of the large fruits. This is done on flower cluster before they have bloomed.

For additional revenue, one can intercrop grapes with crops that mature early, do not deplete soil nutrients, and can not be inflected with disease harmful to the vines. Mungbean is an excellent intercrop if planted beneath the trellis.

Hormones or growth regulators may be used to increase fruit size and growth. For table grape varieties, gibberellic acid can be applied on flowers before blooming. This, however, must be used with caution.

Fertilizer Application

Determine the nutrient status of the soil with the help of the soil analyst and apply the necessary kind of the fertilizer. Nitrogen, potassium and phosphorus are essential to the growth of the grapes, as well as the small quantities of zinc, magnesium, iron and manganese. Apply these in regular intervals and in small doses.

A more specific method of applying these would be as follows:

Two weeks after planting, dissolve 12 grams of 45-0-0 (nitrogen) in 1 1/2 liters of water and pour into the soil around the plant base. Apply the same amount every 15 days until the third month.

From the forth to the ninth month, apply 40 grams of 45-0-0 (nitrogen) fertilizer and 30 grams of 14-14-14 complete (nitrogen-phosphorus-potassium) fertilizer every month. Mix these with the soil 15 cm away from the plant base.

Ten to eleven months after planting, apply 100 grams of 45- 0-0 (nitrogen) fertilizer plus 80 grams of 14-14-14 complete fertilizer once a month, around the plant base. After 12 months apply 135 grams of 45-0-0 plus 135 grams of complete fertilizer in the same manner.

During the fruit-bearing stage, steps in applying fertilizer are as follows:

Growth Stage / Fertilizer / Manner of Application:

1. Pruning time / 100-125 grams of 16-0-0 +100 -125 grams of complete fertilizer/ Mix with the soil 30-60 cm away from the plant base
2. Fruiting /100-125 grams of 45-0-0 + 100-125 grams of base complete fertilizer / Mix with the soil 30-60 cm away from the plant
3. Change in fruit color / 200-250 grams of 0-0-60 / Mix with the soil 30-60 cm away from the plant base
4. After harvest / 250-300 grams of 14-14-14 / Mix with the soil 30-60 cm away from the plant base
5. Rest period of one to two months / 250-300 grams of 14-14-14 / Mix with the soil 30-60 cm away from the plant base
6. 1-2 weeks after second pruning / 100-125 grams of 16-20-0 + 100-125 grams of complete fertilizer / Mix with the soil 30-60 cm away from the plant base
7. Second fruiting 100-125 grams of 45-0-0 + 100 -125 grams of complete fertilizer/ Mix with the soil 30-60 cm away from the plant base
8. Change in fruit color / 300-500 grams of 0-0-60 / Mix with the soil 30-60 cm away from the plant base
9. After harvest / 250-300 grams of 14-14-14 / Mix with the soil 30-60 cm away from the plant base
10. Rest period of one to two months / 250-300 grams of 14-14-14 / Mix with the soil 30-60 cm away from the plant base

Pest and Disease Control

The downy mildew disease is characterized by yellow and brown spots on the leaves and fruits causing the leaves to wilt and fall. Spray infected vines with Grape fun fungicide, Dithane M-45 or Manzate D before and after flower blooming stage. Repeat application after 7 to 10 days, following the manufacturer’s recommendation.

The anthracnose or bird’s eye rot disease will cause leaves to have dark color margins. Treat the vines with the following fungicides: Grapefun, Dithane, M-45, Manzate D, Orthocide 50 or Phaltan as a control measure before infection start. Repeat application after 7 to 10 days.

When fruits are infected with light-colored spots, spray the vines after fruits have emerged with Orthocide 50, Captan or Captex. Spray again after 7 to 10 days.

The powdery mildew disease which is prevalent during the dry season results in cobweb-like white patches on the vines, which later become dark brown in color. Spray the vines with Karothane 25 (wp) 2 to 3 times before the flowering stage and a week after. Some cultivars, however sensitive to this fungicide.

Mature plants susceptible to rust which are small, yellow and rust-coloredspots on the leaves. Remove all infected leaves and spray the underside of the rest of the leaves with Grapefun, Dithane M-45 or Manzate D. Repeat application 7 to 10 days later.

During the rainy season when plants are more susceptible to disease, it is best to spray fungicides regularly as a preventive measure.

For pest control, follow this procedure:

Pest Description / Pesticide:

• Mites Extract plant sap causing the vines to grow stunded / Spray with Azodrin 168 EC, Kethane 18.5 EC, Endosulfan 35 EC, or Dursban EC every 7 days. Stop application 7 days before harvest. Follow manufacturer’s dosage.
• Scale Cause vines to insects become scaly or flaky white / Azodrin 168 EC, Endosulfan, Malathion, or Diazinon. Application same as above.
• Meanly Results in sooty folance of leaves, shoots and canes; bugs and sticky appear shriveling /
• Azodrin 168 EC, Thiodan, low above dosage – Malathion or Diazinon.
• Vinegar fly Thrives on the fruit / Malathion or Diazinon
• Cutworms Caterpillars feeds on the leaves and fruits / Dursban EC, Sevin 85
• Grape flea Feed on the leaves or beetles buds / Azodrin 168 EC, Thiodan, Dursban EC (manufacturer’s dosage)
• Leafhoppers Cause white specks and yellow blotches / Azodrin 168 EC, Thiodan, Endosulfan, or Dursban EC. Application according to manufacturer’s recommendation
• Prevent birds and bats from feeding on fruit by covering fruit cluster with perforated materials paper bags. Do this before fruits have change color.
• Inspect the vineyard regularly for pest and diseases. Cultivate regularly to control weeds.

Harvest

After barriers and fruit stalks have change color, taste the fruit near the tip of each bunch to determine whether it is ready for harvest. If it tastes sweet, the whole cluster is ready for picking. Harvest by hand with the aid of the sharp shear early in the morning. Include the length of the fruit stalk to facilitate handling.

Keep harvested fruits from being exposed to the sun. Trim, grade and pack them immediately. Sort them according to size and handle carefully to avoid bruising.

Planting Tips and Maintenance

1. Plow and clean the field for planting.
2. Remove the plant from the nursery pot and place in the prepared holes for planting about 3-4 meters apart, row by row.
3. If the seedling comes from a (rooted) branch, do not let this branch touch the soil so that it will not grow roots.
4. At first, cover the new plant with coconut leaves or banana leaves.
5. Prepare the trellis.
6. Apply fertilizer — animal manure: (pig, chicken), decomposed leaves etc.
7. When the stem becomes brown and a new shoot grows and the leaves become mature, it is good to prune the branch.  It is good to do this at the onset of Summer so that the flowers will become fruits and ripen, if sunshine is abundant. Harvest can be had in 3-4 months after pruning. Prune again 4-6 weeks after harvesting. Pruning is done 2-3 times a year, depending on the rain and variety of the grape plant. Reducing of branches is done to make the fruits grow well and large — January, April and June.
8. Remove the growing shoots at the base of the plant or under soil. Do this in the first 4-5 years of the plant.
9. Counteract the insect pests or worms by spraying Brodan or Planters Malathion.
10. Drive away the birds that feed on the grapes by using a scarecrow.
11. Control molds with fungicide about 2 times a week if the weather is humid.

For longer shelf life of the harvested grapes:

1. Harvest only when the sun (day) is cool.
2. Take care not to hurt the fruits when handling.
3. Do not expose them to the heat of the sun.
4. If possible, smoke first the fruits before transporting.

Sources: www.elgu2.ncc.gov.ph, www.region10.dost.gov.ph; Photo: monsterrebellion.wordpress.com