While hedges are fairly low maintenance, every living thing appreciates a little care. Your hedge will thrive with water, food, and the occasional trim — but it’s less fond of weeds and pests. A small amount of attention goes a long way, so read on to learn how to keep your Living Walls™ instant hedge happy and healthy.
We’ve grown your hedge for you — now here’s how to help it thrive.
We’ve gathered everything you need to know below — simple steps to keep your instant hedge looking lush, green, and thriving all year round.
Why it matters
Like all advanced-grade plants, instant hedges and pleached screens need deep, consistent watering while they establish — especially through their first two growing seasons (spring to mid-autumn). Even once established, they’ll still need extra water in long dry or windy spells. Deep, infrequent watering encourages strong roots and long-term resilience.
How to water
Drip irrigation is ideal. We recommend (and can supply) 13mm x 2.2L/hr x 30cm Flow Regulated Landscape Drip Line, which delivers about 7.3 litres per hour per metre directly to the root zone. Lay it over the rootball close to the trunks, secure it with pins, and connect to your hose or irrigation system. Avoid leaky hoses or sprinklers,* which can waste water and wet foliage.
For shorter hedges or container plantings, consistent hand watering works well. Pleached screens and containers can also use individual drippers available from garden retailers.
*Leaky hoses and sprinklers can encourage fungal problems, especially in humid weather, and water unevenly — some plants may be overwatered while others are too dry, making it hard to control how much each hedge receives.
How much water does your hedge need?
While establishing, water deeply one to three times a week depending on your hedge variety, soil, season, and weather. Adjust for your conditions — more often in summer, less in winter. Hedges in hot, windy spots may need up to 25% more water, while cool or sheltered sites with heavy soil may need less. Increase watering where tree roots compete nearby.
The soil should feel moist about 5cm below the surface — not dry, not soggy.
As a general guide:
100L hedge: ~7.5 litres per metre — about 1 hour for the full hedge row using our drip line
70L hedge: ~4–5 litres per metre — about 30–40 minutes for the full row
25L hedge: ~2.5 litres per metre — about 20 minutes for the full row
What about rain?
Light rain often won’t penetrate the hedge foliage to reach the roots — especially under dense canopies. Check the soil after rain; if it’s dry a few centimetres down, keep irrigating.
Pro tip
In very light soils or containers, install a permanent irrigation system. Once potting mix dries out, it becomes hydrophobic (repelling water), so extra watering may be needed to re-wet it.⬆︎
Feeding for healthy growth
Regular feeding helps your hedge establish quickly and maintain strong, healthy foliage. Use a slow-release granular NPK fertiliser such as Nitrophoska®, Nitro Blue, or Triabon®.
Feed in early spring and again in mid-summer. Sprinkle 50–100 grams per metre of hedge (about one to two handfuls) evenly over the soil surface. Keep fertiliser off the trunks and foliage to avoid burn, and water in with a hose after feeding, especially if the foliage is dense.
Once your in-ground hedge is fully established and has reached your desired height, you can reduce feeding to once a year in early spring. Hedges in containers or planters should continue to be fed twice yearly.
Mulching for soil health
After feeding, apply a 5cm layer of well-composted organic mulch each spring. Mulch helps conserve moisture, improve soil structure, and suppress weeds. Keep it clear of trunks and lower branches to prevent rot.
Learn more
For more detail on why and how fertiliser works, see our blog: Feeding Your Hedge for Long-Term Health. ⬆︎
Formative trimming
Formative trimming — shaping young plants into a hedge — is already done for you. That’s one of the big advantages of buying a Living Walls™ instant hedge.
Maintenance trimming
The timing and frequency of trimming depend on the plant variety and the finish you want. Most hedges benefit from trimming 2–3 times per growing season (spring to mid-autumn). This encourages dense, even growth and fresh new foliage. Do any harder cutbacks in spring (corrective trimming), when plants are growing most actively.
If you want your hedge to grow taller, still trim the top lightly to promote denseand even growth.
• Trim flowering hedges after flowering.
• Trim fruiting hedges after fruiting.
Trim on overcast days or in the evening to avoid leaf scorch — and ideally not while birds are nesting.
Tools and technique
• Hand shears make clean cuts on smaller or broad-leaved hedges.
• Battery-powered trimmers are ideal for longer hedges and efficient maintenance.
Trim sides first, then the top. For taller hedges, taper the sides slightly (5–10° from vertical) so sunlight reaches the base — this prevents lower leaf loss, especially for sun-loving species like Pittosporum.
Use string lines for guidance if you prefer a perfectly straight finish. Once your hedge has filled out, trim only the new growth to maintain shape and density.⬆︎
Before Planting
Remove turf and weeds along the hedge line before planting. Grasses compete with young roots for water and nutrients, slowing establishment and growth. Keeping the base of your hedge clear in the first two years makes a big difference to its health and density.
Mulch Matters
Apply a thick layer of mulch to suppress weeds, retain moisture, and regulate soil temperature. Keep the mulch a few centimetres away from hedge stems to prevent rot, and top it up each year as it breaks down.
If Using Sprays
Where chemical control is needed, use contact herbicides containing Glufosinate, or organic alternatives such as Hitman®. These target grass and broadleaf weeds and are not absorbed by roots, so they’re safer around established hedges.
Take Care When Spraying
Avoid contact with green hedge stems, leaves, or soft bark — spray only weeds. Apply on a calm day to reduce drift, and consider using a spray shield or cardboard guard to protect nearby plants.
⚠️ Never use systemic herbicides such as glyphosate (e.g. Roundup®) near your hedge or any desirable plants. Systemic sprays are absorbed through roots and can severely damage or kill your hedge.⬆︎
Healthy, well-fed hedges are usually resilient and can handle the odd pest or disease. However, even the best-kept gardens are artificial environments — so occasional problems can crop up. Good drainage, regular feeding, and choosing the right variety for your location will prevent most issues.
Below are a few of the most common problems seen in New Zealand hedges, how to recognise them, and what to do.
Psyllids
What to look for: Tiny winged insects or flat, shell-like juveniles that cause blistering or little “lumps” on new growth — most common on Pittosporum and Syzygium in spring and summer.
Why it matters: Light infestations are mostly cosmetic and short-lived, but heavy infestations can distort new shoots.
What to do:
• Check that the psyllids are alive before spraying — live ones are cream-coloured, while brown ones are dead, and empty indents mean they’ve left.
• If active, treat 2–3 times during spring and summer with a systemic insecticide such as Cyrus® (imidacloprid).
• For an organic approach, spray Eco-oil™ regularly following label directions.
• After control, trim off damaged leaves as they won’t recover. Dispose of the trimmings to avoid harbouring pests.
Prevention: Keep hedges healthy and regularly trimmed — psyllids prefer soft new growth.
Scale Insects
What to look for: Tiny, mussel-shaped insects fixed to leaves and stems. Affected leaves often yellow and develop sticky honeydew, which attracts black sooty mould. Common on Corokia, Syzygium, Camellia, Ilex, and Citrus.
Why it matters: Heavy infestations can weaken plants and make them unsightly.
What to do:
• Wipe small infestations off by hand or prune out affected stems.
• For larger infestations, use the same systemic insecticides as for psyllid control (Cyrus® or GroVentive® Garden).
• Natural predators (ladybirds and parasitic wasps) often help control scales — so avoid unnecessary spraying.
Prevention: Maintain good airflow through the hedge and avoid excessive nitrogen fertiliser, which encourages soft growth that pests love.
Thrips
What to look for: Silvery streaks or speckles on leaves, often with tiny brown spots underneath. Adults are black; nymphs are cream. Common on Photinia, Citrus, and Bay hedges, especially in hot, dry spots.
Why it matters: Mostly aesthetic — leaves can look dull or distorted if severe.
What to do:
• Apply 2–3 sprays of a systemic insecticide during summer, as for psyllid control.
• Focus on the undersides of leaves and repeat if the problem persists.
Prevention: Avoid planting thrips-prone varieties in hot, dry, sheltered sites. Keep hedges well-watered and mulchedto reduce stress.
Root Diseases (Phytophthora, Pythium)
What to look for: Drooping or yellowing leaves, wilting, or dieback starting from the base. Affected plants may have black-stained tissue at the stem base (“collar rot”).
Why it matters: These fungal diseases attack roots and can kill entire plants, particularly in heavy soils that are soggy in winter and dry in summer.
What to do:
• Improve drainage and avoid overwatering.
• Drench soil with a phosphorous acid fungicide such as Foli-R-Fos® or Foschek™ if symptoms appear.
• Remove severely affected plants and treat the soil before replanting.
Prevention: Don’t plant susceptible species (Griselinia, Michelia, Olearia, Corokia) in wet or compacted soil. Mulch with organic matter to encourage a healthy root zone.
Myrtle Rust
What to look for: Yellow-orange powdery patches on soft new growth — typically on Syzygium, feijoa, and bottlebrush.Leaves may twist or die back.
Why it matters: This fungal disease spreads easily and can disfigure new shoots.
What to do:
• Avoid trimming during warm, humid months when the fungus is most active.
• Use copper-based fungicides as a preventative, or Vandia® or Kiwicare Plant Health Spectrum as curative treatments.
Prevention: Maintain airflow around plants and monitor new growth regularly during summer.
Need help?
If you’re unsure what’s affecting your hedge, professional spray contractors such as SprayTek (Auckland) can identify and treat hedge problems. Your landscaper may also offer a maintenance service. ⬆︎
