Wednesday, January 15, 2014

Grow Pechay without Soil (Hydroponics)

 Dr Abe V Rotor 

NOTE: Hydroponics solutions are specific to specific crops, unlike foliar fertilizers, fertilizer sticks and "magic fertilizers" claimed for general use.  The rule is, formulate your own in a laboratory.  It is a chemist's work, and the setup is designed for a particular crop.  The Bureau of Plant Industry, UPLB and other agricultural institutions can be of assistance regarding this soiless culture technology. (Commercial ready made hydroponics solutions are rare to find. AVR August 3, 2016)

 Among Filipinos, perhaps the most popular leafy vegetable next to kangkong is pechay (Brassica chinensis).  No beef or pork stew (nilagang baka or baboy) is without pechay, so with “kari-kari,” a specialty originally made from ox tail topped with bagoong 
alamang (shrimp paste). Pesang dalag (mudfish stew) is without pechay.  Fried meat with pechay is common in carinderia. Pechay salad, anyone?  

     What do we get out of pechay?  What nutritional value does it have which contributes to health?

     According to nutritionists, pechay is rich in vitamins, iron, phosphorous and calcium. Vitamins and minerals constitute the so-called “glow” food group, which together with “go” food (carbohydrates) and “grow” or protein-rich food, completes the balanced diet pyramid.  Vitamins and mineral are keepers of good grooming, and protect the body from the attack of harmful bacteria and fungi.  They also make our bones and muscles strong, and make us active and attractive, adding zest to life.
Laboratory Analysis Report

     Nutrient analysis was conducted on pechay grown on two mediums by the Central Analytical Services Laboratory of the National Institute of Molecular Biology and Biotechnology (BIOTECH) of UPLB.  Organically grown pechay (cultured in conventional plots fertilized with organic matter such as compost), was compared with pechay grown on hydroponics solution (soiless medium). Here is the result of the comparative analysis.

Table 1 – Food Nutrients
Medium Used    % Ash   %Crude Protein   % Crude Fiber   % Crude Fat

1. Org Fertilizer    1.06                 1.19                   0.38             0.09
2. Hydroponics     1.23                 1.32                   0.51             0.11

     Other than minerals and vitamins, we get from pechay digestible fiber which helps in the elimination of wastes and toxins from the body.  Regular elimination of toxins protects us from diseases such as colon cancer, kidney and liver ailments. It makes us more active and resistant. Although low in crude protein and crude fat, the amount is nonetheless important in supplementing poor diet.

     The advantage of hydroponics grown pechay over organic fertilizer grown pechay is in the amount of calcium, while the difference in iron is not significantly different as shown in this table.

Table 2 – Mineral Nutrients
Medium Used            Total P (ppm)  Total Ca (ppm)  Total Fe (ppm)

1. Org Fertilizer                 381.33                 918                   25.81
2. Hydroponics                  322.33               1400                   28.17

     Higher calcium content in hydroponically grown pechay is traced to the volcanic cinder used as substrate to keep the plant upright and its roots well spread in the solution. 

     These findings were derived from a group thesis conducted by   Anthony Pantaleon, Ian Sampelo, and Jason Javier, entitled Comparative Nutritive Value of Pechay Grown Organically and in Hydroponics in Tagaytay.  It is a collaborative work between this research group from the College of Pharmacy of the University of Santo Tomas and the University of the Philippines at Los Banos. (Author served as thesis adviser to the UST group.) The samples were procured from commercial farms in Tagaytay that grow vegetables using both mediums. The increasing popularity of organically grown food on one hand, and the commercialization of hydroponics grown vegetables in the Philippines, on the other, has opened a new interest on the subject of nutrition.

Mineral Nutrients
     Iron (Fe) aids in the oxygenation of the body through the lungs and blood.  Since oxygen is essential to life, people who lack iron are anemic, docile and sickly.  The most practical source of iron is leafy vegetables.  Aside from pechay and other members of Family Brassicaceae (formerly Cruciferae), sweet potato or kamote tops (Ipomea batatas) is an excellent source of iron.

     Phosphorous (P) is important in the proper functioning of the brain and nerves, for which it is also referred, “brain element”. Iodine and phosphorous are very important in brain development of young people. Adequate phosphorous is also derived from other vegetables, meat and fish, grains, seeds and nuts. 
 Calcium (Ca) is important to long life because it does not only build but rebuild tissues in the bones and muscles - and all cells of the body for that matter.  Since women deplete calcium faster than men, higher calcium intake is recommended specially toward the menopausal stage. Other sources of calcium are milk, other vegetables, specially onion, cereals, poultry and fish. Calcium maintains balanced pH (acidity-alkalinity level) in our body, and promotes the production of hormones.

     People who are well provided with calcium have large and heavy bones. They are active workers and athletes and are sexually active.


     Hydroponics is not new in the country.  Way back in the 1950’s, the former Araneta Institute of Agriculture (now De La Salle University (Araneta) had been growing tomatoes and other vegetables in soilless medium or hydroponics. I had a chance to study and work on  hydroponics in its modern greenhouses. The professors of the institute were some of the country’s foremost scientists like Dr. Nemesio Mendiola, Dr. Eduardo Quisumbing, Dr. Deogracias Villadolid, Dr. Juan Aquino and Dr. Fernando de Peralta, who were then professors in this first private agricultural college in the country.

     These scientists saw the need for a scientific approach in agriculture even as Mindanao then was newly opened to agriculture.  It was the first time I realized that if we want to have food that is nutritious and safe, we must be able to control both the physiology of the plant and the environment in which it is cultivated.  These scientists were talking of agriculture very much ahead of their time.  

     Today the best tomatoes are grown in hydroponics.  In Japan I saw large-scale hydroponics in sprawling greenhouses covering several hectares of floor area.  Plants grow on continuously flowing solution without soil, systematic and fully computerized.

     In Taiwan, off-season melons are grown in hydroponics in greenhouses. They command premium price locally and abroad.  In Israel,  hydroponics is practiced virtually in the middle of the desert, a modern version of the biblical saying, “the land flowing with milk and honey.” 

     To give an idea what the solution contains, the formula is one that is based on specific nutrient requirement of a particular crop in its various stages of growth and development. Dr. Fernando de Peralta based his formula on University of Nebraska hydroponics and modified it according to local conditions for common crops, like tomato.

      For a hydroponics project, here is the procedure and the materials required.

1.         With 20 liters water, mix potassium nitrate, 20.1 gm; calcium nitrate, 6.7 gm; double superphosphate, 5 gm; and magnesium sulfate, 5.0 gm. 
2.         Separately mix in 1 liter the following: iron sulfate, 26 gm; manganese sulfate, 2.0 gm; basic lead, 1.6; zinc sulfate, 0.8; copper sulfate, 0.5. 
3.         After pre-mixing each group, add the second solution to the first and measure at least 18 liters. Together with tap water the remaining balance will be used to replace evaporation as may be needed. 
4.         Start with seedlings, of say, tomato.  Be sure they are sturdy and uninjured.  Keep them in place with string and mesh wire, care being undertaken to keep the roots undisturbed while the shoot is held upright towards the source of light.  

     Organic farming on the other hand follows the conventional method of cultivating crops on plots.  The big difference is to use organic fertilizer prepared from compost and farm residues, instead of chemical fertilizer.  Generally, organically grown plants are healthier and sturdier than those applied with chemicals. Chicken droppings are effective in controlling soil pest like nematodes, crickets, grubs, damping-off fungi and bacterial wilt.  Because of this there is little need to protect the plants by spraying chemicals.  If spraying cannot be avoided, use botanical pesticides such as nicotine, garlic extract, derris, and the like, which are safe to health and the environment. 

     Here is an insecticide solution against common pest of pechay.  In 5 liters of water, mix garlic extract from a whole bulb, and a little  Perla soap. (This brand uses coconut oil in saponification, most commercial brands used fossil-based oil.) Filter and use this solution as spray, or with the use of sprinkler. It is best to apply after watering the plants, so that the pesticide effect remains longer or until the next watering. Repeat application until the plants are two weeks old.   

     Repellants like garlic, lantana, chrysanthemum, ginger, and the like, have been found to keep off many insect pests, thus eliminating the need to spray with chemicals. Do not hesitate to consult your local agriculturist.

The Hydro Garden, Talisay City, Cebu, of Ms Ulyssa Marie. Practical hydroponic gardening - passion and hobby. 

Grow Pechay  at Home
First, sow the seeds in seed trays made from discarded carton egg trays, one to two seeds per “hole” or socket.  At transplanting time, scoop each seedling from the tray without damaging the roots, and transfer it to a one-liter plastic pot filled with soil and compost.  This substrate is prepared by scraping the topsoil of a garbage pile.  Include the ash.  Sieve to remove other materials. 

     Old tires can be used in place of pots.  It can accommodate up to twenty plants.  In 30 days you can start harvesting pechay, leaving the smaller ones to allow them to grow further.  You may harvest only the mature leaves so that you can have a continuous supply of this vegetable until it flowers and produces seeds, in which case you can start a seed nursery for a second or third crop. 

     Why buy pechay when you can raise it at home, either through organic farming, or hydroponics -  or by simply growing them in pots or old tires.  Think of both economics and ecology: nutritious food, good health, outdoor exercise, source of income, and a beautiful and clean surrounding.

Organic Pechay: Corazon showing her organically-grown pechay
500 model farmers will be trained on organic farming to increase their production at the same time mitigate climate change. They will establish model farms and teach the technologies to other farmers.

Acknowledgement: Internet


Imy Barrientos said...

nakakatuwa ang galing :D this blog will really help me in my project thankss :) Godbless

Imy Barrientos said...

ang galing thank ypou po Godbless :)

Roy Galang said...

This blog will really inspires me so much ...hoping that i can grow pechay too...thanks:)

Anonymous said...

Hi doc. Where can I buy those chemicals used for the hydroponics solution? Thanks!