Location: Application Technology Research
Project Number: 5082-30500-001-076-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 18, 2025
End Date: Sep 17, 2029
Objective:
Objective 1: Identify the optimal irrigation frequency and nutrient concentration for tomato seedling production in recirculating sub irrigation systems.
Objective 2: Selection of suitable cherry and grape tomato cultivars for Florida greenhouse conditions.
Objective 3: Determine the best locally available substrate and nutrient concentration for maximizing tomato yield, quality, and flavor.
Objective 4: Evaluate the feasibility of growing tomatoes as a 9-month crop (September to May) under Florida greenhouse conditions.
Approach:
Objective 1: Identify the optimal irrigation frequency and nutrient concentration for tomato seedling production in recirculating sub irrigation systems. Previous research by the PIs identified organic substrates that can replace imported mineral wool for high-wire crop propagation. Recirculating propagation units reduced waste of nutrients and provide protection from water shortages as compared to overhead irrigation. In this experiment, tomato seeds will be grown under three irrigation frequencies and two nutrient concentrations. Seedling quality, transplant success, and production time will be evaluated.
Objective 2: Selection of suitable cherry and grape tomato cultivars for Florida greenhouse conditions. This experiment will use buckets in a polycarbonate-covered greenhouse. Cherry and grape tomato cultivars from U.S. companies will be propagated as described in Objective 1. Following propagation, seedlings will be transplanted into buckets filled with wood fiber and coir substrates. A standard nutrient solution will be applied using commercially available hydroponic fertilizer. Fertigation will be delivered via two drip emitters per plant, operating hourly from 6 a.m. to 6 p.m. daily. Weekly measurements will include leaf count, flower count, and fruit count. Nutrient deficiency symptoms and common disorders will be recorded. Mature fruits will be harvested twice weekly, and fresh and dry weights of fruits and biomass will be measured. Mid-season and final fruit samples will be analyzed for total anthocyanins, phenolic compounds, lycopene, and vitamin C. Leaf tissue nutrient analyses will be conducted at an analytical laboratory.
Objective 3: Determine the best locally available substrate and nutrient concentration for maximizing tomato yield, quality, and flavor. Tomatoes will be grown in previously identified locally available substrates under greenhouse conditions. Six treatment combinations will be tested, consisting of two fertilizer concentrations and three substrate types. Plants will be grown for nine months. In addition to growth parameters mentioned above, flavor analysis will be conducted. Common physiological disorders such as blossom-end rot and edema will also be evaluated.
Objective 4: Evaluate the feasibility of growing tomatoes as a 9-month crop (September to May) under Florida greenhouse conditions. This experiment will integrate findings from Objectives 1–3 to develop a comprehensive production protocol for greenhouse tomatoes in Florida. Tomatoes will be grown under greenhouse conditions with and without supplemental lighting to reflect the variability among small- to medium-scale growers. Plants will be cultivated for nine months, and a cost-benefit analysis will be conducted. Data will be analyzed.