Work out mulch film requirement instantly with clear inputs, formula shown and shareable results.
Plastic mulch is sold by weight, so the covered area must be converted through thickness and polythene density of about 920 kg/m3: weight = area x thickness in metres x 920. A 5% allowance covers tucking film into the trench at bed edges and ends.
Film weight
Area = bed length x film width x 1.05; weight (kg) = area x thickness (micron) / 1,000,000 x 920
Used agricultural plastic film must be collected and disposed of through an authorised recycler. Burning it in the field releases toxic emissions and is illegal in most jurisdictions.
25-30 micron for a single short crop, 50 micron where the film must survive a long-duration crop or two seasons. Thinner film is cheaper per square metre but tears during laying and weeding.
Silver-black reflects light and repels aphids and thrips, useful in vegetables. Plain black warms soil more and suppresses weeds at lower cost.