Pruning, Training and Plant Maintenance
Pruning is controlled wounding for a purpose: health, safety, form, flowering or fruiting. Candidates must understand plant response: apical dominance, auxin, adventitious buds, and how cuts stimulate or suppress growth. Learn pruning types - thinning (removes a branch to the origin), heading (shortens a branch), and the difference between renewal and maintenance pruning. Know the timing rules: prune flowering plants after flowering; avoid pruning in frost or disease-risk periods; and know why some plants (maples, birches, stone fruit) are timing-sensitive.
Understand the cut: a clean cut just outside the branch collar, no flush cuts, no stubs, and the three-cut method for heavy limbs. Training shapes young plants: central leader, modified leader, vase, espalier and pollarding. Maintenance includes deadheading, mulching, weeding, staking checks and tool hygiene between plants.
Traps: topping trees; leaving stubs; painting wounds (generally not recommended); and pruning at the wrong season and losing flowers. Another trap is assuming all plants respond the same way to hard pruning.
Worked rule of thumb: the 'three Ds' first - remove dead, diseased and damaged wood - then crossing and rubbing branches, then shape. Always cut to a bud or branch, and keep tools sharp and clean. For a flowering shrub, prune immediately after flowering unless it flowers on new wood.