ASHS 2025 Conference

Plugs of various Philodendron cultivars, such as ‘Moonlight’, ‘Green Princess’, ‘Birkin’ and ‘Imperial Green’ are readily available to Florida commercial foliage growers. Although older generalized recommendations for producing philodendrons exist, specific production guidelines are not available for many newer cultivars. Growing a crop of foliage plants like philodendrons to completion not only provides for development of grower guidelines but also provides excellent research method learning experiences for undergraduate students. Each year, in September, tissue-cultured plugs of various philodendrons are potted up in 15.24cm standard pots using conventional peat/perlite soilless mixes amended with dolomite, STEM, and several different rates of various controlled-release fertilizers (CRF). The pots are placed on greenhouse benches in randomized blocks within a split-plot design under two different shade levels. The controlled-release fertilizers (CRF) should release evenly at soilless medium temperatures up to 30°C. Throughout the production schedule (usually September to March), medium temperatures are measured using Onset HOBO MX2202 Bluetooth data loggers buried in several pots; light level, temperature and humidity at plant height are also measured. All pots receive the same irrigation treatment. Non-destructive plant growth parameters, such as plant height and number of leaves, are collected frequently. Leaf chlorophyll content is measured several times using various different chlorophyll meters. Leaf color is measured with various color meters. Electrical conductivity (EC) and pH for all pots are measured using the standard pour-through method to evaluate the overall fertilizer levels available; these leachate sample solutions are collected and evaluated in the lab for nitrate, phosphate, potassium, calcium, and magnesium concentrations in the leachate solutions using different types of meters. At the end of the six-month growing period, plants are moved to another location, randomized, and then evaluated by student buyers not involved in the production of the crop. This marketing survey allows us to check for differences between treatments that might impact consumer acceptance. Destructive measurements, such as leaf chlorophyll content and/or leaf chemical content can also be measured after the marketing survey. Statistical analysis is also performed on the collected data. Since the data types are varied, students are introduced to several different statistical techniques from standard deviation to variance to correlation to regression. After completion of the production study, student participants often publish manuscripts and give presentations at conferences. Grower production recommendations are also offered.