There’s something satisfying about trimming a hedge – until you step back and realise that it’s all just a bit wonky
Hedge-trimming and shaping is an horticultural art form. While we’d all like to embrace our inner Edward Scissorhands, learning how to trim or shape a hedge correctly takes years of practice, an eye for detail and more than an ounce of patience.
What do you need to know about trimming a hedge?
Before you sharpen the shears and let loose, there’s three key things you should know, prior to starting the annual trim and shape.
When to trim or shape your hedge?
Most hedges are best trimmed just as you’re coming out of the Melbourne winter and before the start of the spring growth. As most plants lie relatively dormant throughout the colder months, reducing their foliage at this time causes the least amount of stress.
If your hedge is deciduous (it drops all of its leaves in winter), shape while the branches are bare and before the start of new leaf buds or flowers.
If your hedge is evergreen, you can shape at any time, however, you must be aware of how much foliage you remove: In summer, no more than 10%, winter you can remove up to 30%.
How to trim or shape your hedge?
Young trees respond better to regular trimming or shaping. Not only does it encourage new growth, but it also removes any branches that may develop deadwood through the tree’s natural detoxification process.
When shaping your hedge, always try to keep the top slightly tapered as this allows the bottom of the hedge to receive sunlight for balanced photosynthesis.
If you’re after a straight edge, set string lines as a guide so you have something to follow.
What can go wrong when you trim or shape your hedge?
Trimming your hedges at the wrong time of year will stress the plant, leading to stunted growth or make it more susceptible to infection and disease. All deciduous plants should be trimmed when they have bare branches.
Not all species of hedging plants like to have a hard or hefty cutback. On certain species, e.g. conifers, cutting back the hardwood will often cause such damage to the plant that it’s not unusual for them to die. Until you know your garden well, or if you’re working with established trees, it’s better to do several smaller trims overall, than one massive shape at the beginning of the season.
Don’t trust your eye to keep your straight edges in line. Even the most experienced horticulturalists use a string line. Quick growing hedging plants can be more forgiving if their trim ends up lopsided, but slow growers like English Box will have you looking at your mis-cuts for many years to come.
And lastly, make sure you clean and sharpen your hedge trimmers or shears before you start the job. You want to make sure you have clean cuts to prevent infections and clean blades to prevent the spread of disease.
If you’re unsure of the species of plant used in your hedge, take a photo and send it to us and we’ll help you identify it.