Use of a synthetic polymer in potting soils to improve water holding capacity

Three rates of the synthetic, hydrophylic substance Permabsorb (1.6, 3.2, and 6.4 gm/1) were tested by growing ryegrass, azalea, and impatiens in a greenhouse mix, consisting of 1 part Spagnum peat moss, 1 part vermiculite and 1 part perlite by volume. The increased water holding capacity furnished by the Permabsorb at 6.4 gm/1 significantly decreased the watering frequency of rye‐grass without affecting yield. All Permabsorb treatments reduced azalea yield because of decreased aeration or toxicity. Impatiens grew poorly in treatments and control. As the Permabsorb treatments and the control were put through wetting and drying cycles, all held less water unless saturated for long periods of time. Nevertheless, the treatments generally held more water and had lower watering frequencies than the control throughout the 5 to 6 month duration of the experiment.