Handheld Sensors Application for Fertilizer Management in Landscaping Ornamental Justifia brandegeana

The over application of fertilizer is becoming too common in nursery production. Many times it is due to the false assessment made on a plant’s nutrient levels based on simple visual analysis. There are alternatives to  visual diagnostics such as plant tissue testing and non destructive hand held sensors. Plant tissue testing can be time/cost ineffective and simultaneously hinder a plant’s health. We will be using non-destructive handheld sensors to obtain qualitative data that correlates nitrogen levels with a plant’s overall health. Nitrogen is an essential component of chlorophyll in plant leaves as well as numerous proteins. Nitrogen is directly correlated with leaf area, leaf weight, and a plant’s overall size. Deficiencies of nitrogen lead to loss of productivity and overall value of a plant. Too much nitrogen also has adverse affects such as stunted growth and overall degraded plant condition. In this experiment, we have used well known hand held sensors (GreenSeeker, SPAD-502, and Li-Cor ) to obtain quantitative data that will express respectively nutrient levels of Justifia brandegeana at various fertilizer treatments. Justifia brandegeana was picked in this experiment based on its economic importance in South Florida’s landscape garden and its inability to maintain proper floral displays without sustained fertilizer treatments. Various fertilizer treatments (0, 20, 30, 40, and 50 g) of 12N-6P-8K (FLORIKOTE, 2 to 3 month release rate, Sarasota, FL)  were applied to monitor the plants with deficient or excessive N amount. Normalized Difference Vegetation Index (NDVI), Soil Plant Analytical Development (SPAD) and Li-Cor sensor readings date have collected at 1, 2, 3, 4, and 5 months after adding initial fertilizer treatments; MAT). The research showed the promising result on application of NDVI, SPAD, and Li-Cor readings in nursery production.