Vertical farming: A potential farming practice for lettuce production

Land for agriculture is becoming limited in urban areas and the concept of vertical farming could help increase land productivity. Therefore, this study was conducted to investigate potential on sunlight availability lettuce (Lactuca sativa L.) production greenhouse system. The experimental design completely randomized with two different systems: Horizontal systems. Ten planting shelves including five horizontal (HS) (VS) three levels as upper (VS_U), middle (VS_M) lower (VS_L) were constructed. Two varieties, ‘Green Oak’ (L. var. crispa) Cos’ longifolia), selected comparative measurement. Lettuce planted both HS VS Photosynthetically photon flux density (PPFD) continuously monitored throughout growing period. height canopy width measured weekly. Leaf fresh weight (FW) dry (DW) also evaluated. averaged PPFD values 245, 217, 158 147 μmol m-2 s-1 HS, VS_U, VS_M VS_L, respectively. Higher observed comparison VS. Values FW DW significantly higher compared In addition, plant growth occurred from while top bottom. Plant densities (24 m-2) 1.5 times than (16 m-2). Light use efficiency pointed out that (0.46 g mol-1) tended have better (0.28 mol-1).