How to Thicken Up Lilly Pilly Hedge

Written By:
Scott Carroll
Published On:
February 6, 2024
Pruning hedge cover

Lilly Pilly hedges are a cornerstone of Australian gardens, celebrated for their lush foliage and vibrant berries. These native beauties enhance the aesthetic appeal of our outdoor spaces and serve as excellent privacy screens in narrow areas

Here, we’re cultivating a thick, lush Lilly Pilly hedge. We aim to arm you with practical strategies that ensure your hedge survives and thrives, transforming your garden into a verdant sanctuary. 

Join us as we explore the secrets to achieving that dense, flourishing barrier you’ve always desired.

Understanding Lilly Pilly hedges

Lilly Pilly hedges, with their robust growth habits, are a testament to the adaptability and resilience of Australian flora. These hedges thrive in various climates, from warm coastal regions to cooler temperate zones, showcasing their versatility across Australian landscapes. 

Preferred for their rapid growth and low maintenance, Lilly Pillys can quickly reach their lush, dense form under the right conditions. They flourish in well-drained soil, rich in organic matter, which underscores their need for a fertile foundation to support their vibrant foliage and fruiting. 

The ideal pH for these plants leans slightly acidic to neutral, ensuring they absorb nutrients effectively for optimal growth. Understanding these characteristics is crucial for cultivating a thriving Lilly Pilly hedge, as it lays the groundwork for successful gardening endeavours.


Benefits of a thickened Lilly Pilly hedge

A thickened Lilly Pilly hedge offers numerous advantages, making it a highly sought-after feature in gardens across Australia. Among these include:

  1. Privacy: A dense hedge acts as a natural barrier, shielding our outdoor spaces from prying eyes and creating a secluded haven to relax and unwind in peace. This lush privacy screen blends seamlessly into the landscape, enhancing the beauty of our gardens with its vibrant green foliage and colourful berries.
  2. Aesthetic appeal: A well-maintained, thick hedge cannot be overstated; it adds structure and depth, turning a simple garden into a landscaped masterpiece. Furthermore, this beautiful flowering hedge can provide a much needed colour splash to any dull space. 
  3. Noise reduction: Its dense foliage absorbs sound, diminishing the intrusion of traffic noise, neighbours, and other environmental sounds. This natural sound barrier contributes to a tranquil garden atmosphere, where the only sounds are the gentle rustling of leaves and the cheerful chatter of birds. 

In essence, thickening a Lilly Pilly hedge elevates our gardens’ visual appeal. It enhances our quality of life by providing privacy and reducing noise pollution.

How to thicken your Lilly Pilly hedge: tips and tricks

Lilly Pilly (Syzygium australe)

With the right approach, you can encourage your hedge to grow denser and more robust, enhancing both privacy and the overall beauty of your garden. 

Whether starting from scratch or looking to invigorate an existing hedge, these strategies are designed to promote vigorous growth and optimal health. Here, we’ll delve into the essentials of cultivating a lush Lilly Pilly hedge:

  1. Initial planning and planting
  2. Pruning Lilly Pilly to encourage growth
  3. Nutritional support for growth
  4. Mulching for health and moisture retention
  5. Addressing gaps and encouraging filler growth
  6. Weed management 
  7. Staying on top of pests and diseases

By following these steps, you’ll be well on your way to achieving that thick, lush Lilly Pilly hedge that’s a sight to behold and a practical addition to your garden. Let’s explore each strategy in detail to unlock the full potential of your hedge.

1. Initial planning and planting

Embarking on the journey to cultivate a thick Lilly Pilly hedge begins with thoughtful planning and careful planting. Our initial steps lay the groundwork for the lush, dense growth we aspire to achieve. Here’s how to start off on the right foot:

Selecting the right variety

Not all Lilly Pilly varieties are created equal when forming a dense hedge. Some species naturally grow more compactly and are more conducive to thickening than others. 

Research and select a variety known for its dense growth habit and suitability to your local climate. Varieties like Syzygium australe ‘Resilience’ or Acmena smithii ‘Minor’ are excellent for their robust nature and lush foliage.

Soil preparation

The secret to a thriving hedge lies beneath the surface. Soil rich in organic matter is ideal for Lilly Pilly roots to flourish. Before planting, enrich the soil by working in generous amounts of organic compost and well-rotted manure. This improves soil structure and drainage and boosts nutrient levels, setting the stage for vigorous growth.

Optimal planting techniques and spacing

Attention to planting technique and spacing is crucial to encourage a thick hedge from the outset. Plant your Lilly Pillys at a distance that allows them enough room to grow and spread but close enough to eventually merge into a solid green wall. 

A general rule of thumb is to plant them at about 70-80% of their mature width apart. For example, if the expected mature width is 1 metre, planting them 70-80 cm apart will promote dense growth. Ensure each plant is placed in a hole twice as wide and just as deep as the root ball, and water thoroughly after planting to settle the soil around the roots.

By selecting the appropriate variety, preparing the soil with care, and employing strategic planting techniques, we set the stage for our Lilly Pilly hedge to grow and thrive and become the dense, verdant boundary we envision.

2. Pruning Lilly Pilly to encourage growth

Pruning is pivotal in encouraging a Lilly Pilly hedge to develop into a thick, lush barrier. 

We can stimulate the plant to branch out more through strategic cutting, filling in gaps and creating a denser appearance. Let’s break down the pruning process into three key stages:

Initial pruning for young plants

Early and regular tip pruning is essential for young Lilly Pilly plants to promote a bushy growth habit. Start this process when your plants are about 30-40 cm tall, snipping off the top few centimetres of each branch. This encourages the plant to produce multiple offshoots from the cut point, leading to a fuller look. 

Repeat this process every few months during the first year or two, using clean, sharp pruning shears to make precise cuts just above a leaf node.

Maintenance pruning

As your Lilly Pilly hedge matures, establishing a regular pruning schedule is crucial to maintaining its density and desired shape. 

Generally, pruning twice a year is sufficient – once in late winter before the spring growth spurt and again in late summer after the main growing season has ended. This helps keep the hedge looking neat and encourages the growth of new foliage, contributing to the overall thickness. 

Additional light pruning in spring can help maintain an immaculate appearance year-round for hedges in warmer climates.

Revitalising sparse hedges

Even well-established hedges can become sparse or leggy over time, but they can be revitalised with hard pruning. The best time for this more drastic action is late winter, just before the plant’s active growth phase begins. Removing dead or diseased branches improves air circulation and light penetration. 

Then, cut back the remaining branches to the desired height and width, remembering that Lilly Pillys can tolerate significant reduction if needed. After a hard prune, provide extra care, such as watering and fertilising, to support the hedge’s recovery and new growth.

By following these pruning guidelines, from the initial shaping of young plants to the rejuvenation of mature hedges, we can ensure our Lilly Pillys grow thick, healthy, and vibrant, forming the perfect natural screen for our gardens.

3. Nutritional support for growth

Ensuring our Lilly Pilly hedges receive the right nutritional support is akin to laying a feast for them that caters precisely to their growth needs. 

Let’s delve into how we can nourish our hedges to encourage robust growth and a splendid display of greenery.

Dynamic Lifter for natives

This organic fertiliser is a boon for native plants, including our beloved Lilly Pilly. Rich in nutrients and designed to release slowly, it provides a steady supply of nourishment without overwhelming the plants. 

Apply Dynamic Lifter at the onset of spring and again in autumn to support vigorous growth throughout the year. Its gentle formula ensures that the sensitive roots of native plants aren’t harmed, promoting healthy soil conditions and robust growth.

Chicken manure and composted manure

Both chicken manure and other composted manures are excellent sources of organic matter and nutrients. They enrich the soil, improve its structure, and enhance moisture retention – all of which contribute to the health and thickness of your hedge. Spread a layer around the base of your hedge in early spring, taking care not to let it touch the stems directly, and water it in well. This natural boost can be repeated annually to maintain soil fertility.

Understanding Seasol

While Seasol is often touted for its growth-promoting qualities, it’s important to recognize it as a health treatment rather than a traditional fertiliser. Seasol enhances root development and improves plant resilience against stress, pests, and diseases. 

Incorporate Seasol into your care routine every two to four weeks during the spring and summer growing seasons for an added health boost. However, complement it with nutrient-rich fertilisers like Dynamic Lifter or composted manures for comprehensive nutritional support.

By providing our Lilly Pilly hedges with the right mix of organic fertilisers and health treatments, we set the stage for them to thrive. This tailored approach to nutrition supports their growth needs. It contributes to developing a dense, vibrant hedge that is a testament to the care we invest in our gardens.

If you’d like a more in-depth review, check out our full breakdown on the best fertilisers for a Lilly Pilly hedge

4. Mulching for health and moisture retention

Mulching is a critical step towards a thick, healthy Lilly Pilly hedge. It’s like wrapping the roots of your plants in a protective blanket that conserves moisture and keeps those pesky weeds at bay. Here’s how to make the most of mulching for your hedge’s benefit:

Choosing the right mulch

Sugar cane mulch stands out as a top choice for gardeners. Its lightweight structure allows it to break down over time, enriching the soil with organic matter. Other excellent options include lucerne, pea straw, or well-composted bark. 

Each mulch contributes to a healthy growing environment by slowly releasing nutrients into the soil.

Benefits of mulching

Applying a generous layer of mulch around your Lilly Pilly hedge does wonders for its health and vigour. Mulch acts as a moisture reservoir, significantly reducing water evaporation from the soil, especially during the hotter months. This consistent moisture level is crucial for maintaining the lushness of your hedge. 

Furthermore, mulch suppresses weed growth, reducing competition for nutrients and water. Weeds can significantly hinder achieving the dense growth you desire, so keeping them in check is essential.

Improving soil conditions

Beyond moisture retention and weed suppression, mulch is pivotal in enhancing soil quality. As it decomposes, it adds valuable organic matter to the soil, improving its structure and fertility. This creates an ideal environment for roots to expand and absorb nutrients more efficiently, directly contributing to your hedge’s thickness and overall health.

For best results, apply a 2-3 inch layer of mulch around the base of your hedge, leaving some space around the stem to prevent rot. Refresh the mulch layer annually or as needed to maintain its benefits. 

Through thoughtful mulching, we conserve water, deter weeds and create the perfect conditions for our Lilly Pilly hedges to flourish and fill out.

5. Addressing gaps and encouraging filler growth

A thick, uniform Lilly Pilly hedge is the goal. Still, sometimes, gaps can appear, disrupting the lush continuity we strive for. Fortunately, these gaps can be filled with the right strategies, ensuring our hedge grows dense and cohesive. 

Here’s how to tackle those sparse areas and encourage robust filler growth:

Inter-planting for immediate coverage

 If you’re faced with larger gaps, inter-planting is an effective solution. This involves planting additional Lilly Pilly plants where the hedge is lacking. 

Choose young plants that match the variety of your existing hedge for consistency in growth and appearance. This method provides immediate greenery, gradually blending with the older plants as they grow and fill the space.

Pruning to stimulate lateral growth

Pruning isn’t just about maintaining shape; it’s also a tool for encouraging the hedge to become denser. Focus on pruning the tips of branches just above new growth nodes. This technique prompts the plant to branch out sideways rather than upwards, filling in the gaps naturally over time. 

For particularly leggy hedges, consider a more substantial cutback to a set of lower leaves to encourage growth closer to the base.

Thinning to improve light penetration

Sometimes, the interior of a hedge can become so dense that sunlight struggles to reach the lower branches, resulting in bare patches. Lightly thinning the upper canopy allows more light to filter through, encouraging growth throughout the hedge. Use this technique sparingly to avoid creating new gaps.

Regular feeding to support filler growth

Providing your hedge with nutrients is crucial for encouraging dense growth. Apply a balanced, slow-release fertiliser after pruning to boost your plants. This ensures they have the energy required to produce new foliage, helping to fill in any sparse areas.

By employing these strategies, we can address the gaps in our Lilly Pilly hedge, encouraging it to grow thicker and more uniformly. Inter-planting offers an immediate solution, while targeted pruning and careful feeding support the hedge’s natural ability to fill in over time. 

With patience and consistent care, those gaps will soon be a thing of the past, leaving you with a beautifully dense hedge that serves as a testament to your gardening skills.

6. Weed management 

In our quest for a thick, vibrant Lilly Pilly hedge, managing weeds is not just a chore—it’s a necessity. Weeds and grass vying for the same precious resources as our hedges can significantly hinder their growth and density. 

Here’s how to keep these unwelcome guests at bay and ensure our hedges have all they need to thrive:

Reducing competition for nutrients and water

Weeds are notorious for their ability to outcompete more desirable plants for nutrients and water. By diligently removing these invaders, we ensure our Lilly Pilly hedges aren’t starved of the essentials they need to grow thick and lush. 

Regular weeding keeps the soil’s nutrient and moisture levels reserved exclusively for our hedges.

Effective weed management practices

  • Mulching: Applying a thick layer of mulch retains soil moisture, improves soil health, and acts as a physical barrier to weed growth. Organic mulches, such as sugar cane or lucerne, gradually break down, enriching the soil while keeping weed seeds from seeing the light of day.
  • Hand weeding: Hand weeding is often the most effective method for immediate weed issues. Pulling weeds out by the roots ensures they won’t quickly return, providing a clean slate for hedge growth. Regular checks and prompt action keep the area around your hedge clear.
  • Herbicide use: In cases where weed infestation is severe, selective herbicides can offer a solution. Choose a safe product for use around Lilly Pilly plants, and always follow the manufacturer’s instructions to avoid harming your hedge. Spot treatments are best to minimise chemical use in your garden.
  • Preventative measures: Preventing weeds before they start is always easier than dealing with them after they take hold. Alongside mulching, consider installing a weed barrier fabric when planting. This physical layer allows water and nutrients to reach the soil while keeping weed seeds trapped below, unable to germinate.

By prioritising weed management, we protect our Lilly Pilly hedges from competition and create an environment where they can flourish. Regular maintenance, combined with strategic prevention, ensures our hedges remain the stars of the garden, free to grow thick and full without interference.

7. Staying on top of pests and diseases

For our Lilly Pilly hedges to achieve that coveted thickness, vigilance against pests and diseases is paramount. These unwelcome visitors can quickly compromise the health and density of our hedges, leading to thinned-out foliage and gaps. Let’s explore how to keep these challenges at bay:

Common pests and diseases

  • Psyllids: These tiny insects are notorious for affecting Lilly Pilly hedges, causing unsightly pimple-like bumps on leaves and leading to foliage loss.
  • Scale: Another sap-sucking pest that can weaken plants by feeding on their sap, leaving behind a sticky residue that attracts sooty mould.
  • Root rot: Overwatering or poor drainage can lead to fungal diseases like root rot, compromising the plant’s root system and overall health.

Regular inspections for early detection:

We recommend making a routine to inspect your hedge closely and regularly. 

Look for signs of pest activity or disease, such as discoloured leaves, unusual leaf shapes, or dieback. Early detection is crucial for effective management and can prevent minor issues from becoming major infestations.

Treatment options

  • Psyllids: Use a horticultural oil or insecticidal soap to treat infested plants. These treatments suffocate the pests without harming beneficial insects. Regular applications may be necessary for severe infestations.
  • Scale: Apply horticultural oil or a specific scale treatment according to the product’s instructions. Ensuring thorough coverage, including the undersides of leaves, is key to success.
  • Root rot: Improve drainage around your plants and adjust watering practices to prevent over-saturation of the soil. In severe cases, affected plants may need to be removed to avoid spreading the disease.

Preventative measures

  • Healthy practices: Maintain healthy soil, ensure adequate drainage, and follow proper watering schedules to keep your hedge robust and less susceptible to diseases.
  • Beneficial insects: Encourage natural predators in your garden, such as ladybugs and lacewings, which can help control pest populations naturally.

We can protect our Lilly Pilly hedges from harm by staying vigilant and adopting a proactive approach to pest and disease management. Regular inspections, prompt treatment of issues, and fostering a healthy garden ecosystem are all key strategies in maintaining the lush, dense hedge we desire. 

For more information on these strategies, check out our comprehensive guide on handling Lilly Pilly problems.

Lilly Pilly Fruit

Seasonal Care adjustments

Caring for a Lilly Pilly hedge isn’t a one-size-fits-all approach; it requires adjustments as the seasons change to ensure it remains thick, vibrant, and healthy year-round. Understanding these seasonal nuances allows us to effectively cater to the hedge’s needs. 

Here’s how to adjust your care routine through the seasons:


  • Watering: Increase watering as the weather warms and growth accelerates. Ensure the soil remains moist but not soggy.
  • Pruning: Perform a light prune to shape the hedge and remove winter damage. This encourages fresh growth and helps maintain density.
  • Fertilisation: Apply a balanced, slow-release fertiliser to support the vigorous growth typical of this season. Incorporating compost around the base can also boost soil health.


  • Watering: Watering needs to peak in summer due to higher temperatures and evaporation rates. Early morning or late afternoon watering reduces water loss and ensures the hedge has adequate moisture.
  • Mulching: Refresh mulch layers to conserve soil moisture, keep roots cool, and suppress weed growth.
  • Pest and disease monitoring: Be vigilant for signs of pests or diseases, which can be more prevalent in warm weather. Treat any issues promptly to prevent spread.


  • Pruning: Conduct a more substantial prune if needed, shaping the hedge before it enters its slower winter growth phase. This is also an ideal time to address any gaps or thin areas.
  • Fertilisation: Apply a fertiliser lower in nitrogen and higher in potassium to strengthen the plants against cold weather.
  • Preparation for Winter: Ensure the hedge is well-watered heading into winter, especially if the autumn has been dry.


  • Watering: Reduce watering as plant growth slows and evaporation rates decrease. Water only if there are extended dry periods.
  • Pruning: Avoid heavy pruning in winter to prevent stimulating new growth that could be damaged by cold. However, removing dead or diseased branches is still advisable.
  • Protection: In colder regions, consider using frost cloth on nights when frost is predicted to protect new growth from damage.

By tailoring your care practices to the specific needs of each season, you can ensure your Lilly Pilly hedge remains a lush, dense, and vibrant feature in your garden all year round. Seasonal adjustments in watering, pruning, fertilisation, and proactive pest and disease management are key to the hedge’s health and appearance.


In conclusion, cultivating a thick Lilly Pilly hedge requires careful planning, strategic pruning, nutritional support, diligent weed and pest management, and seasonal care adjustments. We can ensure our hedges grow dense and vibrant by embracing these practices. 

Let’s apply these strategies in our gardens, embracing consistent care and maintenance to achieve the lush, thriving Lilly Pilly hedges we aspire to!