Artificial stone For Garden XL-01

What problem it solves

Some outdoor utility elements are not tall — they are wide. A large concrete manhole cover (DN600 or DN800) sits flush with the lawn, interrupting the green surface with a grey industrial circle. A septic inspection hatch protrudes a few centimetres above grade. A recessed irrigation valve box, a cable junction cover, or a sealed well casing breaks the visual continuity of an otherwise considered garden.

These wide, flat objects create a specific design problem. An upright boulder — even one with the same coverage diameter — looks disproportionate when placed over a flat manhole: a 37 cm tall stone over a 5 cm protrusion resembles a boulder dropped from the sky, not a natural part of the landscape.

The XL-01 resolves this with a fundamentally different form. At 125 × 97 cm and only 23 cm peak height, it lies across the lawn like a massive flat field stone that has always been there. The 1.21 m² base area covers not only the utility object itself but also its surrounding frame, the disturbed soil ring, and the zone of disrupted lawn — restoring visual coherence to the entire area.

Budget plastic covers in this size category are rare, structurally weak, and visually unconvincing. Natural flat stones of comparable dimensions weigh 500–1,000 kg and require heavy machinery to deliver and place. The XL-01 bridges this gap: realistic stone appearance, engineered composite strength, and a weight that two people can handle comfortably.

Construction, installation & technical specifications

The XL-01 is a hollow shell with a wide, elongated profile — 125 × 97 cm at the base, rising from approximately 13 cm at the edges to 23 cm at the central peak. The interior provides a usable coverage diameter of ~80 cm.

Installation takes under five minutes. Place the stone directly over the target object on any surface. No anchoring, no foundation, no tools. The large base area (1.21 m²) provides natural ground contact and stability.

Transport and placement require two people — at 16 kg and 125 cm length, comfortable handling needs two adults. Equipment access requires only one person — lift or tilt the stone to inspect or service the concealed installation, then lower it back. This is the key operational distinction for daily use.

Wind consideration — the large flat surface area can catch wind from below in exposed locations. In such cases, landscape anchoring stakes at the perimeter provide additional security, though this is not mandatory for most residential installations.

Seasonal behavior is neutral. The fiberglass composite structure does not absorb water, does not expand or contract meaningfully with temperature changes, and tolerates a continuous operating range from −30 °C to +60 °C. The stone performs identically in summer heat, autumn rain, and winter frost. It does not need to be removed, covered, or stored during any season.

Base contact — the stone has a non-sealed base and rests directly on the ground surface. It is not hermetically sealed; natural micro air exchange between the interior cavity and the surrounding environment is possible through the ground contact zone.

Safety and load limitations — the product supports 100+ kg of static load under normal conditions. It is not a load-bearing structure, is not designed for impact loads, and is not intended for jumping or active play without prior structural adaptation of the product. Use in children's and public zones is possible with a pre-agreed usage scenario, engineering adaptation of the structure, and coordination of safety requirements.

Technical specifications

Material & durability philosophy

The XL-01 is constructed from a multi-layer fiberglass composite (GFK) — the same class of material used in boat hull construction, chosen for its strength-to-weight ratio and long-term weather resistance.

The outer surface is a marble chip and marble powder gelcoat of the ISO/NPG class. The color is not painted, printed, or applied as a film. Natural stone chips and stone dust of different colors are mixed directly into the gelcoat compound during manufacturing. The color and grain are embedded in the material itself, producing a surface that ages gracefully rather than peeling, flaking, or fading.

The product is handcrafted (In Handarbeit gefertigt) — color and dimensional deviations of 3–5 cm are within normal range and contribute to the natural stone appearance.

Compared with typical alternatives:

The XL-01 occupies a position that neither extreme can reach: far lighter and more practical than a natural flat stone of the same dimensions, far more durable and visually convincing than budget plastic — and uniquely combining a hollow interior with a load-bearing, marine-grade composite shell at a scale that budget alternatives simply do not offer.

Maintenance is minimal. Clean occasionally with water and a soft brush. No sealing, repainting, or chemical treatment is ever required.

Warranty

The GARTENDEK warranty on artificial stones is 5 years from the date of delivery.

The warranty does not cover:

• mechanical damage;
• cosmetic changes (natural gelcoat matting, minor degradation of the outer layer due to UV exposure);
• exposure to aggressive chemicals;
• use other than intended;
• modifications not agreed with GARTENDEK.

The warranty applies in addition to the consumer's statutory rights under applicable EU legislation.

Real use scenarios

Manhole cover concealment

The most common XL-01 application. A large concrete or cast-iron manhole cover (DN600/DN800) protrudes 5–15 cm above the lawn — the flat slab silhouette mimics a naturally embedded field stone, and the 125 × 97 cm base area hides the cover, its frame, and the surrounding ring of disturbed lawn.

Septic hatch coverage

A flush-mount or slightly raised septic inspection hatch (ø 60–75 cm) disappears under the XL-01's flat profile, sitting naturally at ground level without the visual absurdity of a tall boulder over a flat installation.

Irrigation valve box concealment

Recessed main valve boxes (up to ø 75 cm, lid at grade level) — the entire box and surrounding area vanish under the stone. Equipment remains accessible at any time.

Underground junction boxes

Cable, telecom, or gas junction covers at grade level — the wide footprint covers both the access point and the surrounding disturbed ground.

Well casing concealment

A sealed well casing protruding 10–20 cm above grade — the XL-01 covers both the casing and the surrounding disturbed soil within its 125 × 97 cm base area.

Tree stump concealment

A cut tree stump (ø ≤ 75 cm) at near-ground level — the flat slab hides the stump and the ring of disturbed soil around it, restoring a clean lawn line.

Decorative horizontal landscape accent

The 125 × 97 cm flat slab creates the impression of a large naturally embedded glacial erratic — an ideal horizontal landscape anchor at garden bed borders, beside water features, or as a focal point in large lawn areas. Many owners use it purely for decoration, without any concealment purpose.

Position inside the GARTENDEK system

The XL-01 is the entry model of the XL-series — and the model with the largest exterior footprint in the entire GARTENDEK range (125 × 97 cm = ~1.21 m²). It belongs to a fundamentally different form category than the S, M, and L series: a flat, low-slung slab (23 cm peak height) designed for horizontal concealment of wide, low-profile objects.

The XL-01 shares its ø 80 cm interior coverage diameter with M-03 and L-01 — but serves a completely different purpose:

Choose the XL-01 when:

• The object to conceal is wide (up to ø 80 cm) but low (≤ ~18–20 cm)
• You need maximum horizontal coverage area with a natural flat stone profile
• The target is a manhole cover, septic hatch, recessed valve box, or similar flat installation
• A tall boulder over a flat object would look disproportionate

Consider a different model when:

• The target object is taller than ~20 cm — choose L-01 (37 cm height) or M-03 (32 cm height) for the same ø 80 cm coverage
• The target object is wider than ø 80 cm — upgrade to XL-04 (ø 90 cm, compact body) or XL-02 (ø 90 cm, maximum footprint in the XL-series)
• A compact upright boulder silhouette is preferred — M-03 or L-01 offer the same ø 80 cm in a vertical form

The XL-01 works as a standalone landscape element or as part of a multi-stone arrangement combining flat XL slabs with upright S, M, or L boulders for a varied, natural-looking stone grouping.

Environmental responsibility & sustainability

6.1 — Material origin & production geography

EU-based production ensures compliance with REACH (EC 1907/2006) and European environmental manufacturing standards. Intra-European supply chains — from raw materials to finished product — reduce transport-related CO₂ emissions by an estimated 70–85 % compared to equivalent products manufactured in Asia and shipped to European markets.

6.2 — Raw material composition & efficiency

The product is a multi-layer fiberglass composite (GFK), built from the outside in:

• Outer layer: ISO/NPG gelcoat with natural marble chips and stone dust — protective, UV-stabilised, colour integral to the material
• Second layer: gelcoat mixed with stone chips — adds texture depth and impact resistance
• Structural core: polyester resin reinforced with fiberglass mat and mineral dust — the main load-bearing shell
• Inner layer: polyester resin with mineral dust — seals the interior surface

The mineral fraction (marble chips, stone dust, glass fibre) constitutes a major share of total mass — naturally occurring, chemically inert, non-toxic. The polyester resin is thermoset: once fully cured, chemically stable, does not release monomers, VOCs, or harmful substances.

The hollow shell design is inherently material-efficient: the XL-01 covers ~1.21 m² with only 16 kg of composite. A natural flat stone of equivalent dimensions would weigh 500–1,000 kg. Unlike wood-plastic composites or multi-polymer laminates, the GFK structure uses a single resin system with mineral and glass reinforcement — simplifying end-of-life processing.

6.3 — Transport & packaging footprint

The product ships in a wooden crate (timber battens), wrapped in PE stretch film with PVC cable ties. XL-series models travel on wooden pallets via specialised carriers.

Packaging is wood-dominant: reusable, compostable, or recyclable as untreated wood waste. PE film is recyclable via standard plastic streams. Cable ties — minimal mass, general waste.

A 16 kg hollow composite delivered by standard carrier replaces the functional equivalent of a 500–1,000 kg natural stone requiring crane delivery and flatbed freight.

6.4 — Product lifespan & replacement cycle avoidance

Declared service life: 10+ years of permanent outdoor exposure without maintenance. Real-world durability extends significantly beyond the declared minimum.

How the product ages outdoors:

• 0–5 years: stable form, minimal surface changes. Gelcoat retains colour depth and gloss
• 5–20 years: UV begins working on the gelcoat — slight matting, possible micro-crazing, gradual colour softening. The structural composite underneath remains fully intact
• 20–50 years: continued slow erosion of the gelcoat surface — the stone becomes slightly more porous, texture coarsens, colour mutes further
• 50+ years: the product still exists and functions. Surface increasingly resembles naturally weathered stone

The key point: the product does not fail suddenly or collapse. It ages gradually — and with age, it looks more like a real stone, not less. Structural functionality is maintained throughout.

Over a 20-year period, one GARTENDEK stone replaces 5–10 budget plastic covers (manufactured, shipped, degraded, disposed of) or 2–4 painted concrete elements (cracked, replaced). Each avoided replacement cycle eliminates: extraction → manufacturing → packaging → transport → disposal.

Zero maintenance further reduces lifecycle impact: no painting, sealing, or chemical treatment ever required.

6.5 — Operational carbon footprint vs natural stone

Natural stone appears inherently ecological — but its real-world carbon footprint is enormous. Quarrying disrupts ecosystems, requires heavy machinery, and generates significant CO₂. A single 500–1,000 kg flat stone demands crane loading, flatbed transport, and heavy equipment for placement — each operation burning diesel and producing emissions.

Every time a garden layout changes — and most gardens are rearranged at least once every 10–15 years — the entire logistics chain repeats: heavy machinery, crane, flatbed, placement crew. Removing a natural stone is just as carbon-intensive as delivering it.

The GARTENDEK composite stone eliminates this cycle entirely. At 16 kg, it is repositioned by hand — two people, no machinery, no emissions, no disruption to the surrounding landscape. It can be moved daily if needed: from one side of the garden to the other, to a new property, or stored temporarily — with zero carbon cost each time.

Over a 30-year garden lifecycle with even one layout change, a natural stone generates multiple heavy-transport events. The composite stone generates none. The seemingly „greener" material turns out to carry a far larger operational carbon footprint than the engineered alternative.

6.6 — End-of-life & material fate

Transparent assessment. GFK composite is a thermoset material — it does not melt, does not dissolve, and is not recyclable via conventional plastic recycling streams. It is not biodegradable.

After its multi-decade service life, the product can be:

• Relocated whole to a secondary location for continued use
• Mechanically crushed and reused as inert construction aggregate — sub-base fill, drainage material, landscape backfill
• Disposed of as inert construction and demolition waste at licensed facilities

Why this is proportionate at the scale of this product:

1. Chemical inertness: Cured polyester resin does not leach harmful substances into soil, groundwater, or aquatic systems. Mineral fillers are naturally occurring geological materials
2. No rapid microplastic generation: Unlike single-use plastics or high-friction items, the product does not shed microplastics during normal stationary use. Surface erosion over decades is extremely slow and localised
3. Scale context: A single 16 kg garden stone, replaced once in 30–50 years, generates negligible waste compared to dominant microplastic sources (automotive tyres: ~1.5 kg/tyre/year; synthetic clothing: microfibres in every wash cycle)
4. Mineral-dominant mass: A significant portion of the product is natural mineral material (marble, stone dust, glass fibre) — chemically identical to geological materials already present in soil

Packaging end-of-life:

• Wooden crate / pallet → reusable as firewood, compostable, or recyclable as wood waste
• Stretch film (PE) → recyclable via plastic recycling
• PVC cable ties → general waste (minimal mass)

6.7 — Harmful substance avoidance

The product contains no harmful substances during normal outdoor use:

• Cured thermoset polyester resin is chemically inert — no VOC emissions, no off-gassing
• Colour is integral to the gelcoat (marble chips in the resin matrix) — no paints, films, or coatings that peel, flake, or shed
• No formaldehyde, phthalates, or heavy metals
• No biocides, fungicides, or preservative chemicals
• Gelcoat surface is sealed — no exposed fiberglass during normal use

REACH compliance (EC 1907/2006) confirms absence of Substances of Very High Concern (SVHC).

6.8 — Alignment with EU sustainability frameworks

• EU Green Deal — extremely long-lifespan product with EU manufacturing, minimising replacement waste
• Circular Economy Action Plan — waste prevention through extreme durability; end-of-life material repurposable as inert aggregate
• ESPR — durable, maintenance-free, relocatable without loss of function
• EU Waste Framework Directive — supports waste hierarchy: prevention (longevity) → reuse (relocatable) → recovery (crushable as inert fill)
• REACH (EC 1907/2006) — compliant, no SVHC substances

6.9 — Environmental summary

Does the XL-01 look realistic, or will people notice it is artificial?

The surface is formed from real marble chips and marble powder embedded in an ISO/NPG gelcoat — not painted. The texture and color variation mimic a natural granite field stone. At normal viewing distance (1 m+), the XL-01 is not identifiable as artificial. The wide, flat, asymmetric form reinforces this — it resembles a large field stone naturally embedded in the landscape.

How many people are needed for installation?

Two people for transport and initial placement — the stone weighs 16 kg and measures 125 cm in length. Installation takes under 5 minutes on any surface, with no tools or foundation. For daily equipment access, one person is sufficient — lift or tilt the stone to inspect or service the concealed installation, then lower it back.

Will it fade or crack after years of outdoor use?

No. UV stability is built into the ISO/NPG gelcoat — the same class used in marine applications. The color is integral to the material, not a surface coating. The declared service life is 10+ years of permanent outdoor exposure without fading, cracking, or delamination.

What is the maximum object size the XL-01 can cover?

The interior coverage diameter is approximately 80 cm, with a peak height of 23 cm (effective internal clearance ~18–20 cm). It is designed for wide, low-profile objects: manhole covers (DN600/DN800), septic hatches, valve boxes, junction covers, well casings. For taller objects (&​gt; 20 cm), consider L-01 or M-03 with the same ø 80 cm. For wider objects (&​gt; ø 80 cm), consider XL-04 or XL-02.

Can I place it directly on grass or soil?

Yes. No site preparation is required. The large base area (1.21 m²) provides natural stability on any surface. In wind-exposed locations, landscape anchoring stakes may be considered as an additional precaution.

How does the XL-01 compare to cheaper plastic covers?

Budget artificial stones in this size category are rare and structurally weak. Most use HDPE or thin polyresin with painted surfaces that degrade within 2–4 seasons. The XL-01 uses a multi-layer fiberglass composite with marble chip gelcoat — the same material class used in boat hulls. The result: 100+ kg load tolerance, 10+ year UV life, and a surface that remains realistic after years of exposure.

Can I step on it accidentally?

Yes. The fiberglass composite shell supports over 100 kg of static load. It tolerates accidental stepping and garden traffic without deformation.

Is the XL-01 available in different colors?

Yes — two color variants: Red and Gray. The color is formed by adding different natural stone chips into the gelcoat compound, so each variant has authentic stone-like color variation.

Can I drill holes for cables or pipes?

Yes. The GFK composite can be drilled with masonry drill bits or hole saws, or cut with a stone-cutting disc on an angle grinder. Walls are typically 10–15 mm thick, so this takes only a few minutes.