Peat and Bark Media Nutrient Levels in Relation to Geranium Growth and Tissue Analysis

Abstract

The relationship between water extraction (1:1.5) values and nutrient uptake in geranium (Pelargonium × hortorum Bailey) growing in moss peat (peat), bark, or moss peat and soil media was investigated. Nitrogen, P, and K fertilizers were incorporated in increments in the starting media and applied again in solution, about at the crop midpoint. Desirable nutrient N(NH4+-N + NO3--N), P(H2PO4--P) and K(K+) values (DV) from media analysis at the start of the experiments (MDV) and midway to flowering (FDV) also were calculated from regression equations on the basis of maximum growth rates, maximum dry weight production at midharvest, and final harvest. The relationships between plant uptake of N, P, and K and the water extract concentrations were generally very good, except for K in bark for both harvests and in peat at the first harvest, and an underestimated P uptake in peat + soil and in bark. The media DV obtained using growth data were broadly similar to those using plant dry weight data, although somewhat lower for N during the early growing period.

Pretreated Eucalyptus globulus and Pinus radiata Barks: Potential Substrates to Improve Seed Germination for a Sustainable Horticulture

“…The results indicate that it can support plant growth and improve soil structure [25][26][27][28]. It should be noted, however, that some bark substrates are susceptible to N immobilization, which affects the availability of this essential element to plants [29].…”

Estimating the chemical composition of the soil solution of glasshouse soil. 2. Relationships between the compositions of soil solution and aqueous extracts.

“…An aqueous-extract technique which has already been calibrated against the soil solution method is the 1:1.5 by-volume extract introduced by Sonneveld et al (1974). It is meant for determining the availability of nutrients in potting composts and growing substrates, and is in use as such (Arnold Bik & Boertje, 1975;Verdure, 1979;von Allmen & Gysi, 1983;Widmer et al 1986).…”