Weed management without herbicides
Attempting organic conversion on a site with serious weed problems will be difficult and expensive. Pre-treatment weed control is considered essential for problem weeds.
Starting with a site that is relatively free from serious problem weeds is an important prerequisite before committing to an organic production system. Vigilant monitoring and timely control of problem weed outbreaks will be important to ensure serious infestations do not get established.
Mowing and mulching
A well established plant cover of preferred species over the orchard floor provides the basis for out-competing and controlling weeds. Managing the orchard floor cover requires periodic mowing and mulching, and these events can be designed and timed to optimise impact on target weeds.
A tractor-mounted mower with spring-loaded retractable outrigger that moves around tree trunks is commonly used. The height and timing of cutting can influence the growth and flowering of different orchard floor species.
For new plantings, heavy straw mulch down rows during the first few establishment years may be useful. The use of barley as an initial cover crop followed by sowing selected orchard floor species can give a solid cover that allows mowing and mulching down the young tree lines. A brush cutter can also used around young trees and other areas where necessary.
In older mango orchards, weed management under stress is usually less problematic due to shading and leaf litter. Seasonal hand weeding of creepers that climb up the tree truck may be required in tropical regions.