Thuja Hedge: Why Experts Are Calling for Removal

Public opinion is turning - and specialists are now sounding the alarm about removing them.

In front gardens across the country, a green staple is starting to crumble: the evergreen Thuja hedge. Once praised as an easy-care fix, it is increasingly revealing itself to be both an ecological headache and an expensive trap for homeowners. Agronomists and landscape planners are now saying openly that the era of these conifer hedges is over - and that in many places they are better off disappearing entirely.

Thuja hedge: the 80s favourite becomes a problem case

Thuja - often sold in garden centres simply as the “tree of life” - was the default choice for fast privacy screening for decades. The formula looked straightforward: plant close together, trim regularly, and you have a solid green barrier. Yet that approach fits less and less with a climate that is becoming hotter and drier.

The key issue is that Thuja has a very shallow root system. The roots remain near the surface and struggle to reach deeper, moister layers of soil. In summers with little rainfall, the plant quickly becomes stressed - even when it is watered regularly.

Studies show that a Thuja hedge can use up to around 60% more water than a hedge made from site-suitable, native species.

Especially in densely built-up residential areas, this intensifies water pressure in the garden. Lawns brown off more quickly, perennials languish, and the watering-can rounds become longer and longer. What was once an “easy” screen turns into a constant drinker that effectively drains the rest of the garden.

Green wall, grey zone for wildlife

A second issue is also becoming hard to ignore: a classic Thuja monoculture provides very little habitat. The dense, uniform needle cover offers limited food for insects, and birds rarely find enough shelter and forage there - particularly when the hedge is clipped into a strict, straight line.

For that reason, numerous municipalities in France have responded by heavily restricting - or outright banning - new plantings of such hedges in their development plans. In some regions, the removal of existing Thuja hedges is even financially supported, provided a diverse, nature-friendly hedge is planted afterwards. The direction of travel is clear: away from uniform green, towards lively mixed hedges.

Stress, beetles, total loss: why many Thuja hedges have no future

The visible decline often starts quietly. Individual sections begin turning brown from the inside out. At first, it can look like drought damage that can be fixed with more watering and fertiliser. That assumption, however, is often the mistake.

In weakened hedges, an inconspicuous but highly problematic pest is showing up more and more frequently: the so-called Thuja jewel beetle, a metallic-looking longhorn-beetle relative. It uses drought-stressed plants as an ideal breeding site.

The larvae bore fine tunnels beneath the bark, straight into the conductive tissue that transports water and nutrients. From the outside, there is initially very little to see. Inside, however, the plant effectively “dies of thirst”, even if the soil may still be damp.

Once a Thuja hedge is heavily infested by the jewel beetle, official guidance notes treat it as practically beyond saving.

Sprays do very little against larvae inside the wood, and severely damaged plants can only be rescued in exceptional cases. If the hedge is left standing, it becomes a breeding reservoir - putting other Thujas and nearby conifers at risk.

Warning signs you should take seriously

Garden professionals point to several clear symptoms where removing the hedge is usually the most sensible option:

• Large brown patches spreading from the inside out
• Dry, brittle shoots that retain their brown scales
• Fine tunnels or feeding marks under the bark when a piece is peeled back
• No new growth from older wood, even after cutting back

As a rule, Thuja does not reshoot from old, fully aged wood. In practical terms, that means once a gap appears, it stays for good. Little by little, the hedge loses its value as a screen and starts to look increasingly uneven.

When it’s the right time to remove it

Anyone planning to take out a diseased or ageing Thuja hedge should choose the timing carefully. Specialist authorities advise against major, radical work between roughly mid-March and the end of July. Many bird species nest in hedges and shrubs during this period. Reaching for a chainsaw then not only destroys nests, but may also breach wildlife protection rules.

Late summer, autumn, or late winter are generally best. The ground is usually workable, and new plants have time to establish at least somewhat before the next hot spell.

How to prepare the ground after removing Thuja

Once the hedge is gone, what remains is often an exhausted, compacted strip of soil. Replanting immediately can easily lead to disappointment. A short interim step works better:

• Remove stumps and thicker root remnants completely.
• Loosen the soil deeply - ideally with a spade or digging fork, rather than only shallow rotavating.
• Work in plenty of well-rotted compost, and for heavy soils consider mixing in a little sand.
• Leave the area to rest for a few weeks or sow a green manure crop.

This allows soil life and structure to recover - a crucial condition for the new planting to grow in healthy and resilient.

What to replace Thuja with

Instead of a monotonous wall of needles, many designers now favour so-called mixed hedges or field hedges. The principle is to combine several native or well-adapted shrubs and small trees that flower, fruit and carry foliage at different times.

Popular building blocks for this kind of hedge include:

• Laurustinus (evergreen, early flowering)
• Photinia varieties with red new growth
• Privet as a classic shrub that tolerates clipping well
• Hornbeam for a dense, deciduous screen
• Hazel with edible nuts
• Dogwood species with colourful bark for winter interest
• Hawthorn as a thorny, bird-friendly refuge
• Ornamental grasses such as Miscanthus for structure and movement

Mixed hedges, on average, need less water, cool the garden more effectively, and provide far more food and shelter for birds, insects and small mammals.

Measurements show these hedges can retain soil moisture noticeably better than a pure row of Thuja. During heatwaves, that difference can shape the whole garden’s development.

How close can you plant - and how high?

When replacing a Thuja hedge, it is worth checking the legal rules at the same time. Setbacks from the boundary and permitted heights are governed by regional law and local by-laws. Typical guidance is around 50 centimetres from the boundary for lower shrubs, and more for taller-growing species.

A varied hedge does not have to be the same height everywhere. Many gardeners now create a stepped profile: lower flowering shrubs towards the street, with taller species behind for privacy. This looks more natural than a rigid, clipped block - and it is easier to keep healthy.

Why saying goodbye to Thuja can be an opportunity for your garden

For many people, taking out an old hedge initially feels like a loss. After all, that green wall may have shaped the garden for decades. But those who embrace a redesign typically gain far more than they give up.

A well-planned mixed hedge delivers:

• Flowers from spring through to autumn
• Autumn colour and ornamental berries
• More shade and cooling for patios and façades
• Livelier bird and insect activity
• A more stable structure in storms and heavy rain

At the same time, watering demands fall when species suited to the site are chosen. With smart planning, maintenance can even reduce: less formal shaping, more gentle pruning at longer intervals.

Practical tips for making the switch

If you are not ready to give up Thuja all at once, an incremental approach can work well. Start by removing the most badly damaged section and replacing it with a mixed hedge. Step by step, this creates a new, diverse border that visually supports what remains.

It also helps to factor in different mature heights and growth speeds from the outset. Fast growers such as privet provide privacy relatively quickly, while slower woody plants in the background add long-term structure. A blend of evergreen and deciduous species keeps the garden from looking completely bare in winter - without falling back into the old monoculture trap.

If you are unsure, seek advice from a local nursery. The specialists there understand the area’s soils and climate. Many businesses now offer end-to-end packages: from Thuja removal and soil preparation through to planting a new, climate-resilient hedge.

Ultimately, the problems facing Thuja hedges do not signal a garden in decline, but rather the start of a shift in thinking: away from a lifeless, thirsty needle wall, and towards living, diverse structures that cope better with climate stress - and make our gardens true places to retreat to.

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