Production Guide on Squash

(Cucurbita moschata Duch)

Squash or “kalabasa” is a viny, creeping and trailing crop producing fruits and considered to be one of the most delicious vegetables.  It is the most commonly and regularly grown among the cucurbits due to its rich source of Vitamin A, phosphorous and calcium .  The young and tender shoots make good vegetable salad.  The fruit is excellent for “ginataan”  especially in the Bicol region.

Though this crop has long been known in the country, its cultivation is mostly confined in the backyard scale.  Most of the areas devoted to squash production are generally the Ilocoas region, Cagayan Valley, Southern Tagalog and Bicol.  However, the premier provinces producing this crop fro semi-commercial scale are Batangas, Laguna, Nueva Ecija, Leyte and Davao.

BOTANICAL DESCRIPTION

Squash is a tender tendril-bearing and viny-like plant belonging to the family Cucurbitaceae of Gourd Family.  It has a very course, prostrate or climbing annual, herbaceous vine, reaching a length of 4 meters or more and flowering throughout the year.  Adventitious roots are also commonly formed at its nodes.  The leaves are broadly rounded and heart shaped. Adventitious roots are also commonly formed at its nodes.    Flowers are erect, lemon yellow to deep orange in color, about 12 cm long, the male flowers with longer peduncles than the female ones 15 to 30 cm in diameter.  The fruits are large and variable in shape, size, color and markings with peduncle that is large, soft and corky on the surface at maturity. Numerous seeds are embedded in the tissue of the placenta which lies at the center of the fruit.

USES AND NUTRITIVE VALUE

Squash is a rich of vitamin A in amount comparable to the degree of yellow color.  The young shoots, flowers and fruits are used as vegetables, it is palatable when cooked alone or in combination with other vegetables, fish and meat.  Matured can be made into pies and other delicacies.  In addition, seeds of mature fruits can be boiled in slated water, dried like watermelon seeds, roasted and used as snack food.

The nutrient values per 100 g edible portion of the fruit contains:

CLIMATIC AND SOIL REQUIREMENTS

Squash can be grown in both wet and dry season.  It has been reported that environment can have a marked effort development and quality of the fruit.  The optimum monthly average temperature for good growth is from about 18⁰C to 27⁰C.  Likewise, warm temperature and low relative humidity favor good fruit-setting development and quality of the fruit.

It thrives on many types of soil but it grows well on organic-rich medium often found on compost or refuse heaps.  A soil pH range of 5.6 to 6.5 is recommended.

RECOMMENDED VARIETIES

1. BPI Sq 1 (Golden squash) – creeping with small, round, golden color fruit.  Tolerant to powdery mildew.  Matures in 778-80 days from planting.  Potential yield is 70-80 tons/ha.  It has higher Vitamin A content. Its vine is short thus, more plants can be planted in the given area.  Skin is smooth and very easy to peel and contains more sugar as compared to other variety.

2. BPI Sq 2 – creeping with oblong fruit with cream stripe and green streak.  The thin flesh is yellow to orange in color.  It is tolerant to powdery mildew and   matures in 95-100 days from planting.  Potential yield is 60-70 tons per hectare.

3. Sampuso – it is a medium early maturing cultivar adapted to both dry  and wet seasons.  The fruit is large, deeply ridged, heart shaped and has an average weight of 2.0 kg.  It has smooth skin which is dark green in color with white speaks.  The yellow orange flesh is thick and of good eating quality.

4. Batac - –a medium size variety and performs well both dry and wet seasons.  The fruit is large, deeply ridged, flat rounded, smoothed-skined and has an average weight of 2.0 kg.  It is dark green brownish orange speaks.  Batac has  yellow orange flesh is thick and of good eating quality.

5. Rizalina – It is an OP variety, extremely vigorous with four to five fruits per plant;  well adapted to both dry and wet seasons;  highly tolerant to squash virus complex and downy mildew.  Fruit is deeply rigged and flat round.  Yellow orange flesh is suitable for baking and cooking purposes.  Maturity days ranges from 102 days to 125 days from planting.

CULTURAL PRACTICES

Land Preparation

Squash can be grown with minimum tillage.  Clear area and dig holes at appropriate distances.  In open field, distance of 2-3 meters between hills is recommended.

Field preparation for squash should be done by twice plowing and harrowing then furrow the field at 2 meters apart.  Furrows are made with a native plow or machine tractor to a depth of 15 cm.

Planting and Spacing 

To plant a hectare it needs about 2-4 kilos of good seeds.  Squash are directly planted at the rate of  2-5 seeds per hill, spaced of 2-3 m between rows and 1 m between hills.  One week after emergence, weak seedlings are thinned out and allow only 2 healthy seedlings to grow. 

Transplanting is also recommended especially for F₁ varieties to saved seeds and insured seedlings establishment.  Sown the seeds in the seedbed and prick individually in the potlet.  Transplanting is done 3 weeks after sowing.

Incorporate animal manure and other compost materials to the soil to improve soil structure.

Irrigation

Vine crops like squash requires an abundant supply of moisture for their maximum plant and fruit development.  Although it is tolerant to drought, but regular irrigation during dry season is highly recommended to obtain higher yield. Irrigate the field by furrow every 7-10 days interval especially during the critical stages such as at planting, vegetative, flowering and early productive stages.    Do not irrigate when the fruits are already mature.

Mulching 

Mulching can be made from rice straw, grass clippings and plastic to minimize weeds and to maintain adequate soil moisture.  It is spread on surface of the ground around the plants.

Fertilization 

The rate of fertilizer depends on soil analysis.  For general recommendation, fertilized at planting time, early vegetative growth, flowering and fruiting stages.  Apply four (4) bags of complete fertilizer at planting time by band placement together with animal manure, it must be mixed will the soil at the rate of 1-2 kg per hill, respectively. 

As the runners are about 30 cms (approximately 2-3 weeks after planting), sidedress  with 3 bags urea (45-0-0) at the rate of 1-2 tbsp/plant.  When the vine of the plant  reaches  90 cms   (one  month after  planting),  sidedress  1 bag  muriate  of  potash (0-0-60) in 1-2 tbsp/plant.  Additional urea and potash may be applied every 15 days whenever necessary.

Weeding and Cultivation 

The most common method of weeding and cultivation are hand pulling and hoeing.  Cultivation starts when the plants are two weeks in order to control weed growth.  Use an animal-drawn plow to lessen cost of weeding.  Shallow cultivation is necessary before the vines cover the ground to keep the soil in good tilth, moist and free from weeds. 

Pest and Disease Management 

Pests

1. Yellow Squash Beetle (Ceratia similes Oliver).  The beetle  eat the leaves resulting in defoliation of young plants.  Severely infested young plants often die while older plants are seriously affected. 

 Control:  Spray any insecticides as soon as the pests damage appear.  Repeat at 7-14 days interval depending on the intensity of infestation.  Spray directly to the leavers, flowers and fruits.  Strict sanitation is recommended.

2.  Aphids (Aphis gossypii Clover).  Adults and young are tiny, green to black and soft bodied.  The leaves become curled and distorted and tend to dwarfing of the plants.

Control:  Spray any insecticides as soon as small colonies appear and repeat at 7-14 days interval. Spray directly to the leavers, flowers and fruits.

3. Red Spider Mites (Tetronychides spp.).  Adults and young are tiny, red or greenish red.  If is found on the underside of the leaves.  Yellow specks and web on the leaves is observe, plants become stunted which result to deformity of the fruits.

Control:  Spray any insecticides as soon as the pests damage appear.  Repeat at 7-14 days interval depending on the intensity of infestation.  Spray directly to the leavers, flowers and fruits.  Strict sanitation is recommended.

4. Squash vine borer (Apomecyna neglecta Pasc).  Larvae is white in color, up 2.5 cms in length.  The larva borer infest the vine, makes hole in stem near the base of runner resulting to runner wilts

 Control:  To effectively control the pests, start application when runners develop and/or before the pest borne into the stem.  Repeat application once a week interval.

Diseases

1. Downy mildew – Pseudoperonospora cubensis Rostow – fungus.  Appearance of yellow spots on the upper surface of the leaves and purplish mildew on the lower side.  The affected plant will not to continue to flower and the develop fruits will be reach maturity.

Control:  Spray with  appropriate  chemicals in  controlling these diseases by following the manufacturer recommendation. 

2.  Powdery mildew – Erysiphe cichoracearun D.C. , fungus.  The presence of talcum-like growth on the leaves surface and young stem is  the first evidence of infection.  Infected tissues may appear normal but later the spots will turn yellow and then dried up.  The infected plants become stunted and the immature fruits force to ripen .

 Control:  When the disease starts to develop, spraying will be at 7-14 days interval.  Use  appropriate  chemicals in controlling these disease by following the manufacturer recommendation.

3. Mosaic virus – Leaves on the older plants are mottled, distorted, wrinkled and the edges curled downward.  The fruit has irregular pale green or white areas scattered with dark green spots.  The younger internodes of the vines become stunted. Thus the young tip leaves form into rosette.

Control:  Rogue the infected plants.  Bury them or burn in an isolated place.  Spraying with insecticides to control the insect vectors will minimize the spread of the disease.

Harvesting 

Pre-mature harvest of the crop reduces its fruit quality, hence, harvesting should be done at the right stage.  Harvest before fruits are fully ripe or when the peduncle starts to dry up.  It is best to harvest the fruits with a portion of the peduncle attached to prolong storage life.

Fruits for vegetables are harvested before the rind begins to harden or approximately 40-100 days after planting while for seed purposes, harvesting should be done when the rind becomes hard and tough or about 120-130 days from planting.

REFERENCES

Tecson, A.M. Squash Production Guide, Bureau of Plant Industry, Horticulture Section. Crop Research Division, Manila

Squash Production Guide, PCARRD. Information Bulletin No.156/2000

Estimated Cost and Return of Production of Fresh Vegetable for 2001. Bureau of Plant Industry. Crop Production Division.

Siemonsma, J.S. and Piluek, K. 1994. (Editors) PROSEA Handbook No. 8 Vegetables. Bogor Indonesia. pp 160-164.

Cost and Return Analysis Per Hectare