2017 ASHS Annual Conference

Mulches have positive benefits for the production of container-grown plants. A novel method of using plastic film mulch for container-grown plants was evaluated. Blocks of 25 Japanese privet (Ligustrum japonicum) in 2.37-L containers that were touching were wrapped with 1.25-mil white or black plastic mulch over the top and sides of the containers. Small plants were planted through the plastic and grown for 22 weeks with overhead irrigation. Water application amount was determined by moisture sensors placed in substrate of each treatment. Plant growth, dry weights, weed fresh weights, weeding time, substrate EC, substrate temperature, total water applied, and mulch costs were determined. Black plastic (BP) and white plastic (WP) mulch reduced water applied by 82 and 91%, respectively, compared to the nontreated control (NT). NT plants grew faster and had more dry weight at the end of the experiment. Mulched containers had fewer weeds and required less labor to remove weeds than NT. Substrate EC was greater in BP and WP than NT after 20 weeks and plastic mulch did not influence substrate temperatures. Plastic mulch added $4.94 per 1000 containers ($2.24 input cost and $2.70 removal cost), not including disposal costs. This novel method of mulching plants could save irrigation pumping, herbicide applications, labor, and potentially fertilizer inputs if production techniques can be refined.