A Cover Rule for Handwoven Shade Cloth: The Widest Tape Spacing That Still Delivers Seventy Percent Shade

Shade cloth for seedlings is specified by the shade it gives, woven by hand at whatever spacing the weaver's eye approves, and the two descriptions meet only by luck. Too open, and the seedlings scorch under a cloth their grower trusted; too dense, and the grower has paid for tape and weaving time to build a still, humid tent that invites the mould the shade was meant to prevent. This paper connects the descriptions arithmetically: cover in each direction from tape width and spacing, shade from the two covers combined, and material used per hundred square metres, and it selects the widest spacing that still delivers a stated seventy percent shade. In the computed results, the chosen pitch mm is 4.5; the chosen shade pct is 74.1; the chosen openness pct is 25.9; the chosen material kg is 24.4; the densest shade pct is 93.3. Weave shade cloth at the widest pitch that meets the shade target, computed from tape widths before the warp is dressed. The study is simulated, not measured; all inputs are stated assumptions, printed in the accompanying computation, which readers may replace with their own values and re-run.