Transplant fertilizer solution and early season plastic mulch increase tomato yield in adequate fertility clay loam soil

It is commonly recommended to apply phosphorus- or nitrogen- and phosphorus-containing water-soluble fertilizers to annual vegetables at transplant to improve establishment and enhance yield. Plastic mulches are also recommended to increase soil temperature and enhance yield through similar root growthpromoting mechanisms early in the season. Our aim was to determine if the recommendations for transplant fertilizer solutions and plastic mulch are justified, and if the effects are interactive in a clay loam soil with moderate or high levels of existing phosphorus fertility and organic matter. We transplanted ‘Plum Dandy’ tomato (Solanum lycopersicum) in 2014 and 2015 into a field with high fertility using black polyethylene mulch or no mulch, and transplant solution containing water, 320 mg/plant nitrogen, or 320 mg/plant nitrogen + 475 mg/plant phosphorus. Mulch was removed 26 to 28 days after transplanting to eliminate midseason and late season mulch effects. We found yield-promoting and maturityhastening effects in both years from transplant solutions containing both nitrogen and phosphorus (18% greater total ripe fruit weight than water control), and similar benefits of early season black plastic mulch (24% greater total ripe fruit weight than no mulch), indicating usefulness of either treatment in tomato production. We found no interactive effects of mulch and transplant solution.