Kawayan charcoal is efficient bio-organic fertilizer

Batac CITY—A retired agricultural scientist in this town has discovered that crushed bamboo charcoal is a very effective component in the organic fertilizer requirement for eggplant, kangkong and other high value commercial crops.

Dr. Stanley C. Malab who was also the former director of the Ilocos Agriculture, Aquatic and Resources Research and Development Consortium (ILAARRDEC)  calls the bamboo charcoal “Kawayan Biochar” (KBC), because when it is mixed with vermicompost and applied to the soil during land preparation, it enhances the soil’s organic matter contents and helps the plants attain their yield potential.

ILAARRDEC is a consortium of 18 government agencies in Region 1 involved in agricultural research and extension. Its main office is located in the main campus of the Mariano Marcos State University (MMSU) in this town.

Dr. Malab found out that the mixture of KBC and vermicompost had markedly increased the soil’s phosphorus content to 301.8 parts per million (ppm) and its potassium content to 1,141.5 ppm. This means the soil was richer of these elements by 500 percent than when it was not applied with this by-product, or even when it was applied with the right amount of bio-organic fertilizer.

In his experiment, Dr. Malab also found out that ordinary garden soils which were not applied with combined KBC and vermicompost contained only a maximum of 0.74 ppm of phosphorus and 265.8 ppm of potassium. When he only applied vermicompost without the KBC, the soil’s phosphorus and potassium contents reached only to about 182.7 ppm and 591.5 ppm, respectively.

Studies have proven that these soil elements are crucial in the life of vegetables and other high value commercial crops. Phosphorus and potassium are known to help the plants develop strong roots, stems, flowers, and bigger and juicier fruits especially during cool weather. It is necessary that plants have substantial amount of these essential soil elements throughout their life cycles.

MMSU charcoal grinder (right) and charcoals from kawayan and corn cobs

Effects of Kawayan biochar on kangkong roots 

Lack of these two important elements will stunt the growth of plants, and make them produce small and narrow leaves, and weak stems and roots.

Its effects on eggplant and kangkong

In his experiment, Dr. Malab found out that kangkong and eggplants fertilized with KBC and vermicompost were healthier than the control plants which did not receive the treatments, and those with were applied with sole organic fertilizer and KBC.

Also, kangkong plants fertilized with KBC and vermicompost were heavier than the other test plants which did not receive the treatments. The main test plants subjected to this new intervention reached an average of 95.9 grams per plant, while those which received sole organic fertilizers reached only an average of 86.3 grams per plant.

Effects of kawayan biochar on kangkong

The control plants which did not receive any treatment had an average weight of 14.6 grams per plant, while those which received sole KBC treatment had an average weight of 19.3 grams per plant. This means that those kangkong plants which were fertilized with KBC and vermicompost were healthier and throughout their vegetative stage.

The same effect was observed in the kangkong plants which tops became bigger and longer than those produced by the control plants and those that were fertilized with sole organic fertilizer. Tops of test plants which received the new technology intervention reached an average of 15.9 cm, while those which received sole organic fertilizer produced tops with an average measurement of 12.7 cm.

The control plants produced the smallest tops which averaged to only 4.1 cm, while those which received only sole KBC produced tops with an average measurement of 6.34 cm.

Dr. Malab also found out that weeks after applying KBC and vermicompost, the organic content of the soil in the test plots was improved by about 4.92 percent in contrast to the 3.31 percent improvement of the soil in the plots which received vermicompost only. Soil in the control plots had only 0.61 percent improvement in its organic matter content.

Dr. Malab also tried the effects of corn cobs charcoal to test if they have the same effects on the test plants. He tried mixing crushed corn cobs charcoal with vermicompost and applied it to the soil intended for kangkong and eggplants. The effect was not as good as those in the combined KBC and vermicompost.  

To get the maximum potential of the combined products, Dr. Malab recommends a 1:1 ratio of vermicompost and pulverized KBC for a one-hectare farm of eggplant or of any other high value commercial vegetable crops. For instance, if the fertilizer requirement of a one-hectare eggplant farm is 8 tons bio-organic fertilizer, reduce the amount by one-half and supply the remaining one-half with KBC.

During the experiment, Dr. Malab noticed significant effects of the applied inputs on the plants at 60 days after transplanting (DAT). The test plants were taller than the control plants and those which only received sole ordinary organic fertilizer and KBC.

Eggplants fertilized with KBC and vermicompost gave a yield of 10 tons per hectare, while those in the other test plot which was applied with a mixture of ordinary organic fertilizer and pulverized corn cob charcoal gave 7.9 tons per hectare.

Effects of Kawayan biochar   vermicompost on eggplant 

Meanwhile, those eggplants fertilized with a mixture of ordinary organic fertilizer and KBC yielded 9.7 tons per hectare, while those which were applied with sole vermicompost yielded 9 tons per hectare. On the other hand, the control plot which did not receive any of the treatments gave a yield of 8.5 tons of fruit per hectare. That’s not all. Eggplants fertilized with KBC and vermicompost produced broader and healthier leaves than those in the different test plots.