Economic evaluation of fruit tree-based multistory cropping systems for marginal lands

Abstract:

Multistory cropping the deliberate arrangement of trees, shrubs and ground-level crops in vertical layers is an old agroforestry practice, yet its economic returns on truly marginal lands have rarely been quantified with the rigour that investors and policy-makers demand. This research evaluated the financial performance of four fruit tree-based multistory systems and a mango monoculture control on degraded Ultisol slopes at the Institut Pertanian Sumatera, Medan, North Sumatra, over six consecutive years (2018–2023). The four systems were: S1, mango + cassava + ginger; S2, rambutan + pineapple + turmeric; S3, durian + coffee + vanilla; and S4, jackfruit + banana + taro. Each system occupied 0.25 ha with three replications in a randomised complete block design. Economic indicators recorded annually included gross revenue, variable and fixed costs, net returns, benefit-cost (B:C) ratio, internal rate of return (IRR) and payback period. By year six, S3 (durian + coffee + vanilla) generated the highest mean net return at 6.21 million IDR ha⁻¹ yr⁻¹ and a B:C ratio of 2.71, driven mainly by rising durian yields and strong vanilla prices. S2 (rambutan + pineapple + turmeric) followed at 5.43 million IDR and a B:C of 2.38. All four multistory systems outperformed the mango monoculture (2.89 million IDR, B:C 1.43) from year three onward, once intercrops began compensating for the immature tree canopy. IRR ranged from 19.7% (S4) to 34.2% (S3), and payback periods fell between 2.8 and 4.1 years. Land equivalent ratios exceeded 1.6 in every multistory system, confirming that mixed planting used marginal land more productively than sole cropping. These findings suggest that fruit-based multistory systems are economically viable rehabilitation options for degraded slopes in humid tropical zones, provided that species combinations are matched to local soil and market conditions.