Fertilization through Wastewater of Croton (Codiaeum variegatum Blume) in Zeolite-Containing Substrates

Petra croton (Codiaeum variegatum Blume) was grown in peatmoss-perlite (PP), singly or with zeolitic tuff (PPZ). When the substrates reached 80% of available water, the plants were irrigated with tap water or wastewater alone or containing (ppm) 100N-44P-83K or 200N-88P-166K. The results indicate that zeolite increased plant width, fertilization increased node and leaf number and wastewater supplemented with 200N-88P-166K increased shoot weight. Tissue N was maximal for PP receiving wastewater or 200N-88P-166K and for both substrates receiving 100N-44P-83K through wastewater or 200N-88P-166K through tap water. Tissue P was maximal for 200N-88P-166K applied through wastewater to PP or through tap water to PPZ. Addition of 100N-44P-83K through wastewater or 200N-88P-166K through either water quality to PP resulted in the highest tissue K. Substrate pH decreased to 4.5 in PP receiving 200N-88P-166K, but increased to 8.3 in non-fertilized PPZ. Values of EC, N, P and Cl were maximal in PP receiving wastewater and minimal in PPZ. Electrical conductivity, N and P were the highest in PP receiving 200N-88P- 166K and lowest in non-fertilized PPZ, whereas K was the highest in PPZ receiving 200N-88P-166K and lowest in non-fertilized PP. The substrate PPZ had higher K and Na than PP. Wastewater increased K in PP and Na in both substrates