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Stockholm Tree Mix

At the forefront of structural soil technology is the Stockholm System, a bespoke mix incorporating biochar and compost to

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£149.80 Per bag

(Excl. VAT £29.96)

Out of stock

SKU: STMSG01 Category:
  • Stockholm tree soil mix is a specialised soil blend designed to promote healthy tree growth in urban environments, particularly in densely populated areas like cities. This soil mix has been formulated to address the unique challenges that trees face in urban settings, such as compacted soil, limited root space, and pollution

    The Stockholm mix is a sophisticated blend designed for maximum efficacy. It is composed of 32-63mm clean stone, combined at a ratio of 1:1 with enriched biochar and compost, constituting 15% of the volume. This composition ensures a stable foundation while maintaining large voids for water movement, air diffusion, and robust root growth. The addition of biochar is a key innovation; it not only enhances soil water retention and nutrient availability but also sequesters carbon, contributing to the mitigation of climate change.

    The success of the Stockholm System hinges on its ability to foster exceptionally healthy urban trees by encouraging deep root growth, thus preventing pavement uplift and ensuring the longevity of both the trees and the urban infrastructure.

    Features and benefits

    Supporting Robust Urban Tree Growth

    Stormwater Management Enhancement

    Mitigation of Urban Heat Island Effect

    Air Quality Improvement and Biodiversity

    Applications in Urban Environments

    Average increase value to the building

  • Physical Properties
    Particle size distribution Composed of a balanced mixture of limestone, compost and BioChar to ensure adequate aeration, drainage, and water retention.
    Organic matter content Contains organic materials such as compost to enrich the soil with nutrients and improve its structure.
    BioChar Enrichment (Carbon Gold) Contains Carbon Gold’s proprietary Tree Soil Improver to support healthier trees
    Porosity Designed to have sufficient pore space to allow for air exchange and water infiltration, crucial for root respiration and nutrient uptake.
    Texture Exhibits a friable texture that facilitates root penetration and growth while providing structural support for the tree.
    Technical Properties
    pH 6.5 - 7.5
    Salinity Maintains a low salt content to prevent salt stress on tree roots and minimize the risk of soil degradation over time.
  • All your materials arrive in one delivery from our UK farm and are simple to unload and install straight away.

    Important Information

    Please ensure that you have suitable means of offload at the delivery address for example forklift or telehandler for this type of product as it cannot be offloaded manually.

  • Popular FAQs

    • Can I still have solar panels?
      Yes. Green roofs can be designed to fit around solar panels or the panels can fit on top of the roof. This can not only increase the efficiency of the solar panels, but the shade created by the solar panels can increase biodiversity of the underlying green roof. Special care must be taken when selecting plants to be installed in the shaded areas to ensure they grow well in low light conditions.
    • Do I need planning permission?
      Most green roofs can be installed with no planning permission, however some do require it. This depends on the location, type of building, height etc and should be consulted before installation. Green roofs are increasingly mandatory for new developments. Planning consent can stipulate that the area must blend into the surrounding landscape or mimic the water runoff of nearby Greenfield sites. Green roofs can allow constructors to overcome these terms.
    • Can I choose what plants to have?
      Sky Garden’s seed and blanket mixes have been specifically designed to work well on green roofs. The thin, low nutrient substrate and exposure can make it hard for some plants to grow well. However we do offer bespoke plants and systems, especially on intensive green roofs. For a full quote and design brief for a bespoke system please contact our sales team.
    • Do I need to water my green roof?
      Sedum is used because it is drought resistant and very hardy. Under normal circumstances the roof should not need regular watering. However, live material must be irrigated immediately following installation. This irrigation must continue in the first few months following installation and again in especially hot and dry periods. Sky Garden recommends full saturation of the system once a week in these periods.
    • How much does a green roof cost?
      Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.
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    Company Brochure

    A comprehensive guide to Sky Garden's green roof systems. Download for detailed information regarding each system available, as well as valuable guidance for maintaining your perfect green roof.


    Sky Garden - Stockholm Mix Structured Tree Soil


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