The objective of these experiments was to evaluate the use of tensiometers to monitor substrate moisture tensions for Metro-Mix 500 and 2 pine bark: 1 Canadian peat: 1 sand (PBPS, by volume) used for container-grown azalea Rhododendron indicum L. `Mrs. G.G. Gerbing' and chrysanthemum (Dendranthema grandiflora Tzvelez.) `Coral Charm.' Commercially available ceramic cups of two sizes, small [0.374 inch (0.95 cm) diameter and 1.125 inches (2.86 cm) long] and large [0.874 inch (2.22 cm) diameter and 3.0 inches (7.62 cm) long] were used to construct pressure transducer-equipped tensiometers. Data from these greenhouse experiments, indicate that either the small or large ceramic cup could be used to monitor substrate tensions at which water would be available to container-grown plants.
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