Using animal manure to grow lettuce (Lactuca sativa L.) in a homemade hydroponics system

Abstract

A Homemade Hydroponics System (HHS) using a continuous solution and air flow system is easy to build, cost saving and eco-friendly when using animal manure as a source of hormones and nutrients in agricultural production. Lettuce (Lactuca sativa L.) was set as a plant model and suspended in a manure solution with a foam platform in a reused foam box, and an air pump was used to provide aeration. Five liquid treatments were investigated on the yield of lettuce: three manures (bat, cattle, pig), commercial chemical fertilizer and groundwater in HHS for 49 days. The pH and temperature did not differ between treatments, but the EC was highest in chemical fertilizer followed by bat manure. Yield was highest (125 gram per plant) with chemical fertilizer closely followed by bat (119 gram per plant), cattle (44 gram per plant) and pig (40 gram per plant) manure. The results confirm that bat liquid manure can use in place of chemical fertilizer for lettuce production in HHS. Moreover, bat manure also has the lowest cost production (0.4 Baht per litre) due to a bat cave being near the experimental area. The usefulness of other animal local manures should be investigated further.