Updated: May 13
There are many benefits of including Biochar when planting trees. Biochar helps to improve both the soil and the tree's health, it helps reduce transplant shock, increase drought resistance and reduce the impact of pests and diseases.
Our Biochar is made from native English hardwoods and is free of chemicals and nutrients (The plant material used in biochar production will determine the efficacy of the biochar).
Hardwood Biochar is of the highest quality and doesn't breakdown in the same way as other Carbon material benefiting the soils structure and fertility for hundreds of years.
It improves the water-holding capacity, nutrient retention, aeration and structure of soils and substrates while increasing the soil microbial activity which promotes the soil’s trace mineral supply and improves plant nutrient uptake and growth.
Water Retention: Biochar retains water in the soil around the roots. This helps young trees through dry periods as they establish.
Carbon Storage: For every tonne of biochar added to the ground, the equivalent of 3 tonnes of Carbon Dioxide is removed from the air and stored for hundred of years.
Healthier Plants: Biochar is proven to boost the health and vitality of plants by holding nutrients and minerals whilst adsorbing toxic chemicals.
See our Horticultural Biochar page for more details about the benefits of including Biochar in your soil.
Our Orchard Experience
We have first hand great results from 20+years ago when we planted an apple orchard incorporating biochar around the root stock. These trees are so healthy now.
There is concern regarding runoff of de-icing salt and heavy metals into tree pits causing damage to urban trees. Urban trees suffer from heavy metal and de-icing salt runoff into soil pits (Salt particularly in cold climates).
Leaching columns set up compared urban soil with 7.5% compost added and 0, 2.5, 5.0 and 7.5% added biochar derived from North American ash. The maximum absorption of both salt (Sodium) and heavy metals Copper, Zinc, Lead and Cadmium added at maximum levels found in urban runoff water was from the 7.5% added Biochar mix. The researchers recommend adding 7.5% biochar to soil pits (Montreal, Canada) when planting trees.
In an experiment Biochar was used to grow tree seedlings in large pots using three urban soils and two tree species. Biochar was compared to Wood-Chip, Biosolids and Compost as a mulch (all applied annually at 25 te/ha). Biochar produced 41% more growth than the control without biochar. Biochar and biosolids produced the greatest biomass yields
The biochar mix also held more water than the standard mix and several of the other mixes as well.
In 2015 Thomas and Gale reviewed current knowledge of forest restoration using Biochar. There were relatively few references found but the main benefits of using Biochar for forest restoration included:
Biochar won’t decompose unlike standard organic soil amendments.
Retains plant nutrients and water in soils.
Sorptive properties – reduced availability of toxic metals, persistent organic pollutants and herbicides.
Schaffert et al. at the Bartlett Tree Research Laboratory, Reading University, outlined a case study where containerised European Beech (Fagus sylvatica) with Biochar added at 0, 10, 15 and 20% inclusion rate (V/V) had significantly reduced mortality rates from 60% reduced to 0%, and leaf colour (SPAD measurements) and crown canopy cover both increased.
Up to 80% of trees planted along the HS2 rail route died after last summer’s drought. For James MacPhail, this suggests not enough is being done to ensure tree growth:
“If you plant 1 million trees, great, but if 800,000 die, was it really worth it?
If you can just do one thing to guarantee the survival of a tree going in the ground then maybe trees can save the planet.”
Forest Research: Tree bark biochar: a green bullet for Scotland’s carbon store
The Guardian: The black alchemy that can arrest carbon emissions