What planting material and spacing should I use for a longan orchard?

Plant longan from grafted or air layered (gootee) material of a known variety rather than seedlings, because vegetatively propagated plants come true to type and bear earlier, while seedlings are slow and variable. Buy from a reliable horticulture nursery, research station, or a litchi or longan growing belt nursery, inspect for healthy roots and a good union, and keep the bill. Spacing is similar to litchi and other medium to large fruit trees, commonly in a moderate to wide range each way that gives a modest number of trees per acre, with the exact figure depending on variety, soil and whether you will manage canopy size, so confirm locally. Use the wide early gaps for short term intercrops to earn while the trees establish. Plant at the start of the rainy season in well prepared pits with organic matter and good drainage, and protect young plants from frost and strong sun. Get final spacing and a nutrient schedule from your KVK.