Pruning Practices in the Landscape
By Gregg O'Connor
Pruning is the selective removal of plant parts to achieve particular results. Pruning is a cultural practice. Along with fertilization; irrigation; mulching; pest/disease and weed control, it plays an important role in helping us to achieve our goals in landscape management as a whole and with particular types of plants.
REASONS FOR PRUNING:
Keep plants from overgrowing their boundaries (if placed improperly). Remove dead, crossing, rubbing, broken, infected, infested or unsightly parts. Promote a denser canopy. Improve flower display. Improve fruit production. Shape into neat, geometric forms. Remove branches or fronds which pose a safety hazards. Rejuvenate old or unhealthy plants. Root prune rootbound plants or girdling roots at time of planting to encourage roots to spread. Remove parts that have reverted back to their less desirable genetic parentage. Train young plants to influence their eventual form and health. Eliminate potential for flower, fruit or seed production in the coming year. Reduce shade to understory plantings or turf. Increase air circulation through a plant/planting. Increase sunlight penetration into plant canopy. Remove suckers from the base of a plant. Remove watersprouts from the branches. “Fix” a poor pruning job. Aim growth in a particular direction. Reduce frequency of need for physical pruning.
THE TYPES OF PLANTS WE PRUNE:
Shade and ornamental trees, Deciduous shrubs, Vines, Groundcovers, Turfgrasses, Annuals, Fruit trees, Palms, Foliage plants, Hedges, Perennials, Nut trees, Ornamental grasses, Conifers, Specimen plants, Flowers, Evergreens, Flowering shrubs, Broadleaf evergreens, Herbaceous plants, Woody plants, Hardy plants, Tender plants, Native plants, Exotic plants, Tropical plants, Temperate plants, Subtropical plants, Edible plants, Herbs, Bushes, Flowering trees, Bulb plants, Landscape plants, Nursery plants, Greenhouse plants, Lianas, Needle evergreens, Deciduous conifers, Ornamentals, Bedding plants, Cycads, etc.
METHODS OF PRUNING:
• Chemical pruning-using synthetic substances (PGRs) to alter plant growth processes “Frost pruning”- removing all freeze damaged portions of the plant, but leaving living tissue to regrow the plant.
• Deadheading-taking off spent flower blooms to encourage more blooms and reduce disease potential.
• Heading back-making a cut just above a shoot bud, branch crotch or node.
• Mowing/Scalping/Verticutting-cutting turfgrasses to maintain dense, low growing groundcover.
• Pinching-using thumb & forefinger to snap off soft, single branch tips, encouraging branching.
• Pollarding-cutting all branches to the same indiscriminate location every year, creating witches broom effect.
• Rejuvenation-removing at least 1/3 of the old stems to the ground, often all stems are cut to almost ground level.
• Root pruning-cutting roots to encourage them to spread outwardly or branch.
• Shearing/Trimming/Shaping/Clipping-cutting off new, soft growth uniformly to form geometric shapes.
• Thinning-removing up to 1/3 of a plants’ stems entirely, to the ground in basal growing plants.
• SOME PROBLEMS PRUNING CAN CAUSE:.
• Removing too much growth can lead to the demise of some plants.
• Pruning at the wrong time can eliminate potential for flower or fruit production for the year.
• Pruning late in the season keeps woundsfrom adequately “healing”. and new growth, is more subject to freeze damage than is hardened growth.
• Pruning of formal hedges so that the top is wider than the bottom reduces light penetration to lower foliage resulting in a thinning of the underparts of the canopy and a gradual decline of the planting.
• Pruning of wet plants can spread infectious plant diseases (fungi, bacteria, viruses).
IN SUMMARY:
Before embarking on a pruning task, accurately identify the plant and determine the purpose the plant serves or the customers’ expectations of it in the landscape. Consider the effect timing will have on the goal of pruning it. Always use sharpened, lubricated and disinfected tools.
