Work on providing growers with another tool to manage plant growth continues at Ohio State. Photoselective plastics are being evaluated for their potential to filter out far-red light in a greenhouse. Far-red is the portion of the light spectrum closely associated with undesirable stem elongation or "stretch". Many plants respond to an absence of far-red by staying compact and dark green even when they become crowded as they grow.

Tomatoes grown under a plastic film shade material in a polyhouse were 20% shorter and had 15% greater chlorophyll when grown under a far-red absorbing plastic shade cloth than when grown in the same house without the additional shade. The reduction in height and darker green leaves occurred even though light was reduced approximately 50% and temperatures were increased approximately 10F in the shaded portion of the house. (Figure 1). (Figure 2).