Horticulture and Vegetable Production: Propagation and Orchard Planning
Horticulture covers fruit, vegetable and flower production: propagation methods, orchard layout, training and pruning, and the vegetable groups that share cultural practices.
Propagation
Sexual propagation uses seed and produces variation, so it is used for papaya, vegetables and rootstocks. Asexual propagation gives true-to-type plants: cuttings (guava, rose), layering (air layering in litchi and guava), grafting and budding (mango, citrus, ber), suckers and offsets (banana, pineapple).
Orchard systems
Square system places trees at the corners of squares; rectangular uses unequal spacing; quincunx is square plus a filler in the centre of each square; hexagonal suits flat land and gives the highest population. Training shapes the young tree, pruning removes growth after bearing begins.
Vegetable groups
Cole crops (cabbage, cauliflower), cucurbits (cucumber, bottlegourd, watermelon), solanaceous (tomato, brinjal, chilli), root crops (carrot, radish), leafy (spinach, coriander), bulb (onion) and leguminous (pea, cowpea).
Worked example
A mango orchard is planted at 6 m × 6 m spacing in a square system. Plant population = 10,000 ÷ (6 × 6) = 10,000 ÷ 36 = 277 plants per hectare. If a filler is added in the centre of each square in the quincunx system, the number of fillers equals the number of main plants, so the total doubles to about 554 until fillers are removed.
Traps
- Confusing grafting with budding, and layering with cutting.
- Forgetting that cucurbits are direct-seeded while tomato and onion are transplanted.
- Planting papaya through cuttings when it is raised from seed.
- Applying the square-system formula to a hexagonal layout without adjusting.