DEJEX SUPPLIES LTD – WRITTEN EVIDENCE (HSI0017)

Author;               Alex Stevenson MBPR (Hort.)

Organisation;              Dejex Supplies Ltd, a progressive family run business specialising in supplying products to commercial horticulture and providing agronomic advice for niche horticultural crops. 

Addressing;              Key challenges, risks, and opportunities facing the sector.  A submission has been made to draw the inquiries attention to an area of Government legislation that may have a significant adverse effect on the commercial horticulture sector.

An accelerated reduction of peat in substrates creates unmitigated risks in horticulture which may lead to a managed decline of the industry.

1              Horticulture is making great strides environmentally, in the areas of packaging, biocontrol, fertiliser efficiency and fresh water usage.  The exception is in the use of substrates where legislation created through lobbying by NGO’s is guiding the industry down a less sustainable path.  The total and accelerated ban of peat in substrates poses a major risk to the horticultural sector, while being detrimental to the Government’s own net zero targets.

What are the increased risks of accelerated peat reduction?

2              Product Costs:  It is technically possible to grow almost any horticultural crop in peat free substrates or without substrates at all.  However, this will significantly increase costs for the grower.  For example, a standard 3lt container substrate mix will go from circa £65 per m³ (30% peat reduced) to circa £95 per m³ (100% peat free).  With the supply of good quality materials limited there will be further inflationary pressure on these prices as the market moves to 100% peat free.  This will be unsustainable for some crops.  Growers who are already 100% peat free in low volumes will also suffer inflationary pressure as large volume producers move to peat free.

3              Supply Chain Costs:  While growing peat free is technically possible some of the materials inherently carry more risk.  Composted green waste is less stable than peat and has a higher probability of contamination with herbicides and heavy metals.  Anaerobic digestate waste contains macro and micro plastic and has unstable nutrient levels.  Coir managed incorrectly has varying Electrical Conductivity (EC).  Timber products decompose in the substrate attracting undesirable bacteria and fungi.  Currently a supplier may deliver a 90m³ lorry of peat containing propagation substrate at circa £5,000, making a few hundred pounds gross margin.  That £5,000 load of substrate could easily grow plants worth £400,000.  With a tried and tested stable substrate this is an acceptable level of return for the supplier as there is low risk of claims and issues.  As the industry is forced to use less consistent alternatives this risk increases, inevitably suppliers will need increase gross margins to make the risk commercially acceptable.

4              Reduced Consistency:  The increased inconsistency of materials outlined in paragraph 3 increases risk for the grower.  Currently the stability of some peat in substrates gives greater buffering for water and nutrients allowing the grower more consistency and greater flexibility in managing the crop.  Removing the peat reduces buffering increasing the risk of crop damage, yield loss or crop failure if there are other issues on the nursery.  This is for both controllable issues, such as failure of mechanical or irrigation systems, and uncontrollable issues, such as weather or supply chain disruption.

Why is accelerated peat reduction a less sustainable path?

5              Increased Fertiliser:  Reducing peat with current alternatives leads to an increased use of artificial fertiliser through a number of mechanisms.  Composted materials are not fully decomposed, therefore when used in substrates the process of bacteria breaking down material uses nutrients, mainly Nitrogen (N).  This N drawdown needs to be buffered by adding extra artificial N to balance the nutrient requirements of the plant.  Most peat alternatives do not have equivalent buffering capacity for nutrients or water, this leads to increased leaching of nutrients through the substrates which have to be replaced artificially.  Most peat alternatives have a higher pH making it difficult to acidify the root zone, macro nutrients are less available at higher pH and some micro nutrients are unavailable for plant uptake at higher pH.  This creates deficiencies that need to be corrected with artificial fertiliser.

6              Increased Water Use:  Alternatives to peat have less water holding capacity.  This requires different watering cycles to keep plants hydrated.  Watering is more regular with increased levels of leaching, most systems within horticulture are not fully recirculating leading to higher levels of fresh water use for the same crop.

7              Increased Transport:  Peat’s unique structure gives it an excellent bulk density for transport while still retaining its physical properties.  Substrates that are peat free require some dense composted materials such as composted barks or composted green waste to achieve water holding and buffering requirements.  This reduces the average volume per lorry load by around 20m³, over an estimated 1.7million m³ of substrates required in commercial horticulture this results in over 7,000 more lorry deliveries in the UK, an increase of over 30%.

8              Increased Biodiversity Loss:  Eliminating the use of peat in the UK will not be possible in the accelerated timescales without the use of coir as a major alternative.  Increased coir use will lead to increased biodiversity loss.  Pristine peatlands are extreme environments meaning they are poor in species although those species are specialised.  Even if peat was harvested from these areas the biodiversity loss would be low.  However, peat in northern Europe is extracted from degraded peatlands previously drained for agriculture or other human needs, so biodiversity loss is negligible.  Coir plantations are in sub-tropical regions that are species rich.  Coir from Coconut Palm plantations has a per hectare biodiversity loss 4.8 times worse than that of palm oil, demand for coir from horticulture and other industries is expanding the development of these plantations.  

9              Increased Waste:  The reduced buffering for water and nutrients of peat free substrates drastically increases waste in the ornamental horticulture supply chain.  More plants are lost on nursery and in store, wastage percentages on peat free product lines can see up to 20% increases on the previous peat reduced substrates.  All the resources that have gone into the production of those plants are completely wasted.  Everything including; plug plant production, packaging, substrate, water use, fertiliser use, labour and transport.  This also ties into higher plant wastage levels by amateur growers as they are forced by legislation to use poor quality substrates.

Why is a ban of peat use in commercial horticulture counterproductive?

10              We can see from the above an accelerated peat ban is going to increase risks for commercial horticulture and will have undesirable effects on the sustainability of substrates.  These factors may be acceptable if they achieved other significant goals such as DEFRA’s net zero targets, NGO’s objectives of preserving peatlands, or the UK Peatland Strategy.  However, in all cases this will be counterproductive.

11              Firstly, ignoring the increased CO₂e issues in use summarised in paragraphs 5-9, the lowest CO₂e substrate to deliver from “cradle to gate” in the UK is still peat, lower than coir, green waste and wood-based products.  However, peat is made of approximately 23% historical captured CO₂ and in carbon accounting methods this carbon which could be 200>6,000 years old is added to the “cradle to gate” total to achieve a “cradle to grave” total that is much higher than the alternatives.  This is treating the carbon stored in peat in the same way as fossil fuels.  The significant difference is nowhere on the planet do we have the conditions to produce more fossil fuels so they are finite, but we have millions of hectares of peatlands that are laying down more plant material as part of the natural carbon cycle.  Peat is a renewing resource, capturing released CO₂ at a faster rate than it is released through horticultural use.  As we restore peatlands this will only increase.

12              Secondly the commercial horticulture industry does not further degrade peatlands.  The UK has 3 million hectares of peatlands, 2.4 million hectares of this are degraded.  Currently around 0.001 million hectares is being harvested for horticulture.  Ceasing harvesting from this area will have no impact on the other 2.399 million hectares that are degraded or areas harvested abroad.  Currently 0.54 million hectares are degraded due to commercial forestry.  As an industry horticulture is being advised to move away from peat towards timber products in a large part grown on degraded peatland.  A small UK peat industry could make the UK self-sustaining in substrates with a mixture of wood products having a positive effect on DEFRA’s net zero targets.  Peat harvesting on lowland raised bogs that are already degraded is the lowest CO₂e alternative activity that can be carried out on bogs and funds a method of rewetting, leaving them in a better state than they were found.  This is a natural resource that should be used, preserved and restored, the use of peat in horticulture and the restoration of peatlands are not mutually exclusive ideas.

Summary:

13              Whilst there are methods of growing commercial horticultural crops peat free there is no economically viable way to scale this industry wide in the time frame the industry has been given until 2026.  Not only this, but scaling using current methods, substituting coir and wood products for peat, is more detrimental to Government net zero policy than current best practice using peat reduced substrates.  Continuing at the current rate will impose higher risks and costs on a low margin industry that could lead to a managed decline of commercial horticulture in the UK.  The UK is uniquely placed to form a best practice peat industry that uses this exceptional natural resource while restoring UK degraded peatlands.  We have the opportunity to create a world class horticulture industry backed by a world class restorative peat industry, regenerating our natural capital rather than exporting our environmental issues abroad. 

4 April 2023