Tomato (Kamatis) Cultivation Guide: All You Need to Know in Planting, Growing and Harvesting Tomato

 

Tomato (Solanum lycopersicum) is a widely cultivated fruit crop in the Philippines due to its versatility in culinary applications and high nutritional value. It is a warm-season crop that can be grown in a wide range of soil types and climatic conditions.

Tomatoes are rich in antioxidants, particularly lycopene, which is known to reduce the risk of cancer and cardiovascular diseases. They are also a good source of vitamins A, C, and E, as well as minerals such as potassium and folate.

Tomato, commonly called “kamatis” in the Philippines, is a highly profitable crop in the country. In 2005, the Ilocos region was the top tomato producer, contributing 22% of the nationwide total harvested area of 17,700 hectares (Bureau of Agricultural Statistics). At the provincial level, Ilocos Norte ranked 5th with 1,195 hectares, following Bukidnon, Nueva Ecija, Tarlac, and Pangasinan.

In the Philippines, the most common tomato varieties grown are Roma, Rio Grande, and Cherry. However, there are also many other varieties available, each with their own unique characteristics and adaptations.

Tomatoes are easy to cultivate and require minimal labor and farm inputs. Many farmers are planting off-season to take advantage of the attractive market prices during the lean supply months. The best planting seasons are from August to November for the first planting, and February to April for the second planting. Sandy to sandy loam soils are ideal for tomato production.

Successful tomato cultivation requires careful planning, from choosing the right variety to preparing the soil, irrigation, pest management, and harvesting. This guide provides comprehensive information on the best practices for tomato cultivation in the Philippines.

Varieties

Select varieties that are high-yielding, early-maturing, tolerant to pests and diseases, adapted to local climatic conditions, and are easy to sell. The characteristics of the varieties that were tested in Currimao, Ilocos Norte and Cabugao, Ilocos Sur during the dry season are shown in the table below.

Variety*	1st harvest	Other characteristics/features
Diamante F1	60 DAT	high yielder, tolerant to heat, semi-indeterminate, 14-15 fruits/kg
Harabas F1	60 DAT	high yielder, excellent for transport, 9-10 fruits/kg
Maguilas	55 DAT	popular during dry season, susceptible to late blight, 20-22 fruits/kg
Mexico	60 DAT	high yielder, resistant to late blight and TYLCV, excellent as table tomato, moderate firmness, 8-9 fruits/kg
Rossana	60 DAT	moderate firmness, high yielder, 10-11 fruits/kg
Seminis F1	60 DAT	high yielder, excellent for transport, 9-10 fruits/kg
Super Pope	60 DAT	good for regular season, 10-11 fruits/kg
Ilocos Red F1	60 DAT	high yielder, processing tomato, excellent for transport, 8-9 fruits/kg

For wet season, the varieties recommended for planting are Diamante F1 and the MMSU hybrids.


Land Preparation

Plow the field two to three times, to help eliminate weeds, hibernating insect pests, and soil-borne diseases. The best time to plow the field is when a ball does not form when the soil is squeezed by hand and only a thin film of the soil sticks to the fingers and palm. Plow at a depth of 15-20 cm.

Harrow twice to break the clods and level the field.

A well-pulverized soil promotes good soil aeration and enhances root formation.


Raising Seedlings

Tomato seeds are tiny, hence, seedlings need to be raised in beds before they are transplanted. Seedlings raised in open field seedbeds are exposed to adverse conditions. Seedling trays use less seeds, promotes uniform growth of superior seedlings, minimize transplanting shock, and lessen seedling mortality. They also provide savings on labor for thinning, weeding, watering, and pest management.

Here’s how to raise seedlings in plastic trays.
 

• Preparing the sowing materials:

1. Prepare the sowing medium by mixing thoroughly 2 parts rice straw compost, 4 parts carbonized rice hull (CRH), and 1 part processed chicken manure (PCM).
2. Fill the holes of the tray with the medium and slightly compact it using your palm.
   
   Use a seedling tray with 100 or 104 holes. The volume of medium in each hole contains enough nutrients to sustain the seedlings until transplanting time.

• Sowing:
  
  A 1000 m2 area (tenth of a hectare) requires 8 g of seeds. One gram (g) is approximately 300 seeds.
  

1. Sow one seed per hole of the plastic tray at a depth of 0.5 cm.
2. Cover the seed with the medium.
3. Water the seeds using a sprinkler with fine droplets.
4. Cover the trays with old newspaper, plastic sack, or rice straw to maintain soil moisture and temperature.
   
   Remove the cover as soon as 1 or 2 seeds have sprouted.
   

• Caring for and maintaining the seedlings:

1. Place the trays on the platforms of a simple nursery. The nursery minimizes exposure of the seedlings to extreme weather and protects them from stray animals.
2. Tomato seeds germinate in 3-4 days under 25 C to 30 C temperature. During colder days, however, germination could take 6 days or more. Remove the cover as soon as 1 or 2 seeds have sprouted.
3. Roof the nursery with transparent plastic sheets during the rainy season; plastic nets or chicken wire during the dry season for the seedlings to take full advantage of the sunlight. Seedlings elongate abnormally when put under the shade.
4. Water early in the morning and afternoon. Apply less water during rainy and cloudy days. The seedlings weaken and elongate with over-watering.

Construction of Planting Beds and Furrows

• When using plastic mulch, construct 1.0 m wide beds raised at 20 cm height. Space the beds 0.8 m apart (refer to Fig.1) to serve as path for manual watering and furrow irrigation.
  
  
  
• For the conventional method, construct furrows (dry months) or ridges (rainy months) of alternating 1.0 m and 0.8 m distances (refer to Fig. 2 & 3). The use of furrows eases irrigation; ridges minimize water-logging.
  
  
  
  
  
  
  

Fertilizer Application

Collect soil samples for analysis at the nearest soils laboratory. Apply fertilizers based on the results of the analysis. Otherwise, use the following recommended rates.

• With plastic mulch

Basal

Make a small furrow on each side of the constructed beds. Apply the following fertilizers every 10 linear meters of a planting row:

• 0.5 kg PCM or any commercial organic fertilizer
• 0.4 kg ammonium phosphate (16-20-0) 0.4 kg ammonium sulfate (21-0-0)
• 0.1 kg muriate of potash (0-0-60)

Cover the fertilizers with soil, or mix them thoroughly with the soil.

Side dress

Drench 170 ml (1 small can of sardines) of fertilizer solution per hill. Follow this recommended schedule, and source and amount of fertilizer to apply.

• Conventional method (unmulched)

Basal

Apply 0.5 kg PCM or any commercial organic fertilizer and 0.4 kg ammonium phosphate (16-20-0) per 10 linear meters planting furrows or ridges. Cover the fertilizers with soil, or mix them thoroughly with the soil.

Side dress

Either dibble the fertilizer at the midpoint (25 cm) between plants along the rows; or distribute it evenly in a shallow furrow 20 cm away from each planting row. For every 2 adjacent beds, the fertilizer furrow must be located at their inner side. Cover the fertilizer with soil.  When irrigating, direct water only at the space between each pair of beds, skipping those on the farther side of the fertilizer furrows. Follow this recommended schedule, and source and amount of fertilizers to apply.

Time of Application                           Amount of Fertilizer
3 weeks after transplanting (WAT)	6 g (0.4 tbsp) urea (46-0-0)/hill; or   120 g (8 tbsp) urea/10 linear meters planting row
6 WAT	6 g (0.4 tbsp) urea/hill and 6 g (0.52 tbsp) muriate of potash (0-0-60)/hill; or   120 g (8 tbsp) urea and 120 g (10.4 tbsp) muriate of potash/10 linear meters planting row

Mulching

The use of plastic mulch is an improved technology for tomato production. It controls weeds, preserves soil moisture, prevents soil erosion and leaching of fertilizers, and reflects sunlight to repel insect pests hiding under the leaves.

Setting up the plastic mulch:

1. Stretch the plastic mulch over the planting bed, with the silver color on top.
2. Fasten the edges of the plastic mulch to the soil with bamboo slats spaced 1.0 m apart. If bamboo slats are not available, cover its edges with soil using a rake, or by passing a moldboard plow near the edges.
   

Making the planting holes:

1. Measure 0.5 m planting distance 10 cm from the edge on both sides of the plastic mulch and mark the spots.
2. Make the holes following any of these three ways:
   
   Using a serrated-lipped tin can: cut the lip of a 7-10 cm diameter tin can with metal scissors to form 1-cm long saw-like edges. Push the can on the marked planting spots of the plastic sheet, serrated side down.
   
   Using a hot tin can: punch small holes using a nail at the sides and bottom of a 7-10 cm diameter tin can. Attach a wooden or bamboo handle. Fill the can with burning charcoal. The small holes ventilate the charcoal to keep it burning.
   
   Using a cutter:  cut intersecting lines 7-10 cm long to form “+” or “x” at the marked planting spots. During transplanting, fold up the 4 flaps to form square planting holes.
   

Transplanting

1. For beds with plastic mulch, flood the beds two days before transplanting to cool down the soil under the plastic mulch and dissolve the fertilizers applied.
   
   For the conventional method, irrigate the furrows to dissolve the fertilizers applied and minimize direct contact of the seedling roots with the fertilizers.
2. Transplant 21 to 30-day-old seedlings, which should now have 3-4 true leaves.
   
   
3. Transplant only one seedling per hole preferably in the afternoon.
   
   A 1000 m2 area (10th of a hectare) requires 2222 seedlings, when using plastic mulch or conventional method. Plant seedlings at 0.5 m distance between hills.
   
   
4. Water the transplants immediately with a sprinkler.

Trellising

During the wet season, raise tomatoes in trellises to avoid vines and fruits from touching the soil. Contact with wet soil results to rotting and disease infection, especially when the plant tissues are injured.

Construct a 1.0-1.5 m high trellis 3 weeks after transplanting.


Irrigation

During the dry season, irrigate once a week until fruit setting. When fruits have set, irrigate unmulched tomato at 10-14 days interval; mulched tomato at 14 days interval until the crop is productive.

During the rainy season, irrigate as the need arises.

Irrigate after every fertilizer application.


Weeding

In unmulched fields, manage weeds by off-barring at 14 DAT and by hilling-up at 21 DAT.


Insect Pests and Diseases, and their Management

1. Leaf feeding 28-spotted lady beetle, Epilachna sp., is more abundant and destructive during the rainy than the dry season. Eggs are laid in mass. The larvae are yellowish but turn white as they approach the pupal stage. They stay in clusters underneath the leaves where they hatch and chew the leaf tissues. The injured tissues turn brown and the leaves eventually die. If the population is high, the whole plant dies.
   
   Manage the pest by handpicking and crushing the eggs or larvae, removing the whole leaf, or uprooting the whole plants and decomposing them in sealed plastic bags.
   
   
2. Common cutworm, Spodoptera litura (Fabr.) is abundant at the vegetative stage of tomato during the rainy season. The pest is also abundant and destructive during the dry season when the plants are fertilized with too much nitrogen.
   
   Manage the pest by collecting egg masses underneath the leaves. Do not apply excessive nitrogen.
   
   
3. Tomato fruitworm, Helicoverpa spp., infests tomato from flower setting to fruiting stage. The larva bores and feeds inside the fruit. At pre-pupal stage, the insect drops to the soil to pupate.
   
   Pathogens enter the fruits through the holes, making the fruits rot.
   
   Manage the pest by not applying nitrogenous fertilizer. Spray green-label insecticide if extremely necessary.
   
   
4. Whitefly, Bemisia tabaci (Gennadius), carries the tomato yellow leaf curl virus (TYLCV). The insect need not colonize the crop to transmit the virus. Even a few whiteflies can cause 100% infection especially in susceptible varieties.
   
   TYLCV infection is highest in susceptible tomato varieties planted from January onwards when the temperature is high, a condition favorable for whitefly infestation.
   
   The pest can be avoided by using resistant varieties. Do not plant late (January onwards) in the season.  Do not spray too much insecticides because natural enemies are killed first.
   
   TYLCV causes stunted growth, yellowing and curling of leaves, and reduced yield. Uproot and burn or bury infected plants.
   
   
5. Late blight is a fungal disease that starts as small yellow spots on the leaves which later turn brown. Eventually, the whole plant dries up. Poor drainage and too much irrigation water aggravate the disease.
   
   Manage the pest by maintaining good drainage and not flooding the field. Plant late blight-resistant varieties.

Harvest and Post Harvest Technology

Harvesting starts 55-60 DAT, depending on variety and intended use of the fruits. Table tomatoes are harvested both mature green and ripe. Green fruits are for transport; ripe fruits for immediate consumption. Harvest glossy green fruits only.

In general, harvest fruits twice a week.

Harvest processing tomatoes when they are ripe. Consult the color chart provided by the processing company.

Separate ripe from unripe fruits to slow down ripening. Ripe fruits emit ethylene that enhances fruit ripening.

To protect tomatoes from transport injuries, pack them in bamboo baskets, plastic crates or plastic sacks.

Checklist and Calendar for Cultivating Tomato (Kamatis)