Why we need to grow more trees – and how aeroponics could help

Trees are hugely important to our environment for two reasons: the first is carbon capture and the second is habitat creation. Trees can absorb and lock up carbon, preventing it from damaging our atmosphere. More than 1.5 million hectares of new woodland is needed to help reach the UK's net zero carbon target by 2050 – that’s almost the size of Wales!

The UK has lost almost half of its biodiversity since the 1970s. This loss of habitat is mostly caused by commercial farming and construction. Around 72% of UK land is managed for agriculture, and only 8% of land is built on. The situation is also severe overseas – tropical forests contain at least half the world’s species, yet we are still clearing around 17 million hectares every year for agriculture and harvesting of timber. Forests are currently being lost globally at a rate 10x higher than any possible level of regrowth.

And biodiversity is also strongly linked to carbon: the IPCC says a 1.5°C average rise may put 20-30% of species at risk of extinction. If the planet warms by more than 2°C, most ecosystems will struggle.

The UK is far more likely to achieve much needed habitat creation than it is are to offset its carbon footprint through tree planting – this is mostly because the country cannot afford to sacrifice enough land for forestry when we have pressing food security issues. That is, it can’t give up agricultural land for forestry at present. However, tree planting projects are still massively important, especially if land that can’t otherwise be used for agriculture is used.

LettUs Grow uses aeroponics to irrigate crops. It’s a soilless method of providing plant roots all the nutrients and water they need with a mist. This mist is created using ultrasonic technology – it uses far less water and fertilizer as well as zero pesticides.

The benefits of using indoor farming systems more generally are that less land is used and they are able to grow all year round. One way these systems could help is actually by freeing up more land for forestry, by growing certain crops indoors.

But the most likely way vertical farming technology could help to grow trees is through propagation. Using aeroponics to propagate tree whips is not only quicker, but uses far less resources, such as water and land. In an aeroponic system, roots have higher access to oxygen, so plants grow stronger and will also avoid soil-borne diseases in their early stages.

Tree planting projects, such as Co-Forest, are dedicated to growing and sustaining forests in the UK. Increasing the amount of forest in the UK is an extremely important source of habitat creation. Not only that, access to green spaces is incredibly beneficial for both mental and physical well-being, as well as for communities.  

Outside of finding land that doesn’t have food value, there are also challenges such as working with utility providers, finding volunteers, and keeping saplings alive in their first few years – the droughts of 2022 were particularly trying!

Propagating trees with vertical farming technology could benefit forestry projects by allowing tree saplings to be grown far more efficiently, as well as being able to produce far more young trees in less space. And this could also extend to farmlands – farmers are increasingly being encouraged to increase biodiversity on their land and make room for forestry projects. Propagating in this way could be a way of allowing farmers to diversify whilst making use of brownfield sites or unutilized barn space.

Propagation of fruit trees in controlled environment agriculture systems could improve the quality, cost and health of young tree whips – while using less resources. In 2021, LettUs Grow partnered with Bardsley England to root, propagate and transplant apple tree whips from cuttings taken from the Bardsley orchards. In the proof of concept trials, all the tree-whips that entered the aeroponic system successfully reached their maximum growth target within two months.

And, of course, community orchards can also give so much to local people, from access to fresh fruits to mental health benefits. Co-Forest is currently searching for land to create their first community orchard!

Another way that trees can help the planet is by providing sustainable energy production through biomass. Biomass is plant matter used as fuel to produce heat or electricity. The Net Zero Strategy is aiming to increase biomass to 7.3% of our energy supply – but this target will be extremely difficult to reach at current tree reproduction rates without importing internationally.

LettUs Grow has partnered with the University of Surrey to use aeroponic technology for the rapid multiplication of willow cuttings. This could accelerate renewable energy production using far less land, resources and carbon. The TAEDA Tech project harvested their first willow cuttings in December and we will be building a unique aeroponic system for greenhouses to continue this research.

Creating a sustainable future is all about having diversity of ideas and solutions. Making sure that we’re including tree planting and habitats within our environmental planning will benefit our planet, ecosystems and people for thousands of years to come. This also means that we should be open minded about how innovative technologies can support non-agricultural efforts – collaboration across industries is absolutely key to unlocking a better future for all.