ARS | Publication request: Boston Fern Prodcution in Whole Pine Tree Substrates

Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: February 2, 2008
Publication Date: June 15, 2009
Citation: Witcher, A.L., Fain, G.B., Spiers, J.M. 2009. Boston Fern Prodcution in Whole Pine Tree Substrates. HortScience 44(3):578.

Technical Abstract: An experiment was conducted to evaluate processed whole pine trees as an alternative container substrate for Boston fern production. Three whole pine tree (WPT) substrates and a commercial peat-lite mix (PL) were each amended per cubic meter with 0.59 kg micromax, 2.37 kg Harrell’s 16-6-12 Plus (4-5 month formulation) and 4.75 kg Harrell’s 18-6-12 (9-10 month formulation). The pH of each substrate was modified with the addition of dolomitic lime (100% WPT = 0.59 kg / m3, 3:1 WPT:Peat = 1.19 kg / m3, 1:1 WPT:Peat = 1.78 kg / m3, and PL = 2.37 kg / m3), each ranging from 4.5-5.0 pH at the beginning of the experiment. On September 21, 2007, liners (10 cm) of true Boston fern (Nephrolepis exaltata ‘Massii’) and dwarf Boston fern (Nephrolepis exaltata ‘Bostoniensis Compacta’) were planted in hanging baskets (25 cm) filled with substrate. Containers were placed on the ground in a shaded greenhouse and drip irrigated twice daily with a low or high irrigation volume. The WPT substrates had a significantly lower pH at 32 DAP and project termination compared to the PL substrate. At project termination, pH ranged from 3.17 in 100% WPT to 5.13 in the PL substrate. Substrate EC was significantly lower under high irrigation (compared to low irrigation) in the PL substrate at project termination for each cultivar. Plants under high irrigation had consistently greater plant growth index (PGI), regardless of substrate. Shoot dry weight (SDW) was consistently greater for plants subjected to the high irrigation treatments, regardless of substrate. No significant differences in PGI or SDW occurred between substrates within irrigation treatments. Differences in substrate physical properties were observed. The PL substrate had 50% less air space and 25% higher water holding capacity compared to the WPT substrate. The air space for 100% WPT was slightly above the recommended range, although all other physical characteristics for each substrate were within acceptable ranges.