Planting Griselinia Hedges: Growth & Care Tips
Griselinia littoralis is an evergreen hedging plant, one of seven species of shrubs that originate from New Zealand. Despite its native homeland, this plant still grows beautifully in several other climates worldwide.
Griselinia littoralis (also known as New Zealand Broadleaf and New Zealand Privet) has become a popular choice for hedging in many UK garden climates. And with its tidy and attractive foliage keeping its evergreen appearance all year long, it’s not difficult to see why the Griselinia species has gained such a strong reputation across the UK and beyond.
But what is the best approach to take when planting a Griselinia hedge? What are they affected by? How can you ensure that your hedge looks lush and attractive all year round?
Here are some of the most important growth and care tips for your Griselinia hedge.
Why are People so drawn to Planting Griselinia?
Griselinia plants are hardy (down to about minus 15). They can endure (and even thrive) in salty air climates and the thick but sturdy trunks of the hedge mean more protection in the average UK garden from powerful coastal winds and the salt spray that comes with it.
The combination of protection and thick foliage that this New Zealand hedge can provide makes them a wonderfully adaptable plant. And while it may be perfect for a coastal seaside garden, this evergreen shrub is also able to flourish in most climates (with the exception of overly exposed and very cold sites in the UK) as long as it’s cared for and planted properly.
When Should You Be Planting a Griselinia Hedge?
The early Spring/late Spring and Autumn periods are the strongest times of year to plant your Griselinia littoralis hedge. This New Zealand plant thrives best in full sun and well-drained soil, which is why so many seaside coastal gardens benefit from this species of tree or shrub.
Understanding how to Plant Griselinia
In order to encourage the fast-growing nature of this New Zealand hedge in your own garden, it’s important to make sure you grow Griselinia in suitable conditions, regardless of how hardy the plant tends to be.
Below are some of the ways in which you can help to plant and grow your hedge to ensure it provides you with colourful foliage, a fast growth rate, and protection against coastal winds.
The Best Way of Planting Griselinia Hedges
Knowing how to plant Griselinia is all about ensuring that your shrub is planted in a suitably prepared hole or trench. The plants should be placed in the ground in a hole that’s just as deep as the root ball. In general, it’s also best to make that hole twice as wide as the root ball.
Once the holes or trench are prepared apply and mix some bonemeal or controlled-release fertiliser into the bottom of the hole/ trench and mix in thoroughly.
Then place the plant into the hole/trench so that the top of the rootball is flush with the soil surrounding it. Next, backfill the hole with the soil you’ve previously removed.
Firm the soil with your foot whilst backfilling to eliminate any potential pockets of air.
Continue filling the hole to the very top, covering the top of the rootball with about an inch of soil and then give the soil and shrub a thorough watering to create a suitable saturation of the root zone.
Finally, cover the base of the hedge with a suitable mulch or groundcover to prevent weeds and conserve moisture. Grow Griselinia in full sun or partial shade to allow the hedge to achieve its full potential.
How far apart Should I Plant Griselinia?
Griselinia hedging is known to be a fast-growing New Zealand species and therefore needs a little space between each plant in order for them to fully shape and thrive. To help this happen, place your plants so there is a small gap between them. This will allow space for the plants to grow but it won’t take years for the gap to fill in. The spacing will depend on the size of the plants purchased. Check first to see how wide the plants are to order the correct amount.
If you’re using small plants to start with and aiming for a lower hedge (up to 6 foot), or a hedge that shapes and grows fast, plant at 30-50cm apart in some well-drained soil. If you want to create a taller hedge or screen then it would be better to plant at 50-75cm apart, allowing the plants more space to fill out.
Propagation of Griselinia Littoralis
A Griselinia littoralis hedge can easily be propagated from your semi-ripe cuttings. If you’re keen on having some semi-hardwood cuttings, the best time to take your cuttings is in the Autumn time or midway through Spring at the latest.
Your Griselinia littoralis stems can be trimmed into cuttings roughly 8 cm in length with a few leaves remaining at the top, ideally cutting just below a node.
Slice a slither off the bottom of the stem, exposing more of the branch at the bottom of the ripe cuttings and dip it in a rooting hormone. You can then place your cuttings into a propagation growing medium.
With the right growing media (ideally well drained) and, if possible, the addition of some bottom heat, your cuttings should start to take root within 4-6 weeks.
Are there any Potential Issues with Planting Griselinia Hedges?
Griselinia littoralis is hardy down to about minus 15 degrees centigrade so the main potential issue is very cold weather. Additionally, like most plants, Griselinia doesn’t like having very wet roots or sitting in water for prolonged periods. This can lead to root rot and potentially lead the plants to fail and die. If your site tends to get very wet, try to improve the drainage with land drains or, alternatively, use a raised bed for your hedge.
Fortunately, on the whole, these plants tend to be very resilient. A Griselinia littoralis hedge can be planted in various common soils (clay, chalk, sand and loam to name but a few), and its hardy nature helps to protect and shelter it from things like pest damage or disease.
Leaf Spots and Pests
In rare circumstances, Griselinia can become susceptible to leaf spot. This is caused by a fungus and is usually a result of humid conditions and poor air circulation around the plants. Noticeable as blackish-brown leaf spots on your Griselinia hedging. The fungus can be treated organically or by using a fungicide (speak to a professional before undertaking any chemical treatment). Thinning out the hedge and allowing better air circulation around the plants will help minimise a fungal attack.
As mentioned before, Griselinia littoralis don’t like very wet and waterlogged soils and this can lead to root rot otherwise known as phytophthora. Prevent waterlogged soils by increasing drainage or using a raised bed for your hedge.
Evergreen Griselinia plants replace their leaves with new leaves coming through. The older leaves tend to fade to yellow before they fall so a few yellow leaves aren’t always a sign of a problem. However yellowing of the leaves on a Griselinia hedge can sometimes be a sign of distress. Often this is due to either very wet or very dry soil or if the plants have been planted in heavy shade. When these symptoms show, just check to see if any of these could be the problem.
The Aftercare of Your Griselinia Hedge Plants
Griselinia littoralis is easily maintained and requires minimal care once the individual shrubs take shape. Simply water it well during dry periods and fertilise annually come Spring.
In terms of pruning advice, it’s best to control the size of your Griselinia hedge plants by pruning them once or twice annually. The pruning can become more difficult if the evergreen shrub has been allowed to grow too thick.
In general, if it’s well looked after, pruning is straightforward and simple.
FAQs about Griselinia Littoralis
If you’re looking to grow Griselinia littoralis trees or hedges, you may have some questions in need of answering. Below are some of the most frequently asked questions about Griselinia.
How long Does it take to Grow Griselinia Hedging?
Griselinia littoralis grows at a rate of between 20-40cm per year and is tolerant to most climates.
How Can You Make Griselinia Littoralis Grow Faster?
You can grow Griselinia faster with regular light trimming and feeding. Make sure the roots stay moist with regular watering whilst actively growing, especially in the hotter months. Adding mulch around the Griselinia will also help them to retain their moisture.
How do you Thicken a Griselinia Hedge?
A nice thick hedge is a huge benefit to exposed gardens. Griselinia can provide this protection, especially in coastal areas that can be buffeted by salt air and wind.
To create a thicker hedge, cut back the leading and side shoots by a third. Trim just above a node/bud from where the new growth will develop. Do this again during the second season of growth to help the plants thicken up the hedge.
Why is my Griselinia Littoralis Hedge Turning Yellow?
As stated above, evergreen Griselinia littoralis plants that experience leaf yellowing are affected by things like disease, insufficient drainage, Insufficient watering or having been exposed to too much shade.
Planting Griselinia Hedges
When growing an evergreen Griselinia Littoralis hedge it’s important for gardeners to know what their plants could be affected by, what they are tolerant of, and what climates they grow well in. Pay attention to the colour of the foliage as discolouration is usually a sign of distress. Whether Griselinia are planted in coastal areas or not, they can create a lush and hardy hedge.
Stick to these tips and with regular pruning and care, you can make your Griselinia grow fast in your garden and enjoy the benefits of this evergreen hedge all year round.