This week, we had to think about what to do about a couple of dying Leylandii plants. They are too tall, partially dead (brown) and also not native to the UK (officially known as x Cuprocyparis leylandii is a fast-growing evergreen conifer hybrid). If they go, soon, I guess, we need to think about what to plant in their places. I don’t really mind that they aren’t native because they are there now, but when they are gone, I’d prefer something more useful. So this gave me an idea to do some research small trees that help to combat climate change. Why? Because beyond how beautiful a plant is, it can serve multiple purposes. So, I thought I’d share my findings in this article with you. I hope you find it useful.

Does Planting Trees Really Help Climate Change?

The simple answer is of course yes, but the reality is more nuanced.

Trees absorb carbon dioxide (CO2), a greenhouse gas that significantly contributes to global warming. By photosynthesis, they convert CO2 into oxygen, thereby reducing the amount of this harmful gas in the atmosphere. According to various studies, a mature tree can absorb around 48 pounds of CO2 per year. Given that deforestation contributes to over a quarter of global greenhouse gas emissions, reforestation and afforestation efforts can serve as important tools in combating climate change. However, let’s also consider the sustainability of tree-planting initiatives. Not all tree-planting projects have the same impact. Planting native species that are well-suited to the local environment enhances biodiversity and resilience against pests and diseases. Trees must be nurtured and protected from threats such as wildfires, invasive species, and urban development, that’s an extra job, it’s not just planting and that’s it. It should not be seen as a standalone solution to climate change, either. 

To stop the climate getting worse, we need to massively reduce the amount of carbon dioxide that we each release (i.e. move towards net zero carbon emissions). But this alone will probably not save us: we need to remove carbon dioxide from the atmosphere faster than it is being released. This is called negative carbon emission.

Why Small Trees Matter

Small trees, often classified as those reaching 20 feet in height or less, have several advantages. Their size makes them suitable for crowded little cottage gardens, and also urban areas where space is limited, because they can be more easily managed. These trees can effectively sequester carbon dioxide, thus improving air quality, reducing urban heat, and also support the local wildlife. Furthermore, small trees still provide shade, like any plant, and of course, every outdoor space looks much better when it’s lush and green.

1 Redbud (Cercis canadensis)

The Eastern Redbud is a top choice for small trees that positively impact the environment. This deciduous tree typically reaches a height of 20 to 30 feet but can be pruned to maintain a smaller stature. It has pretty pink blossoms and heart-shaped leaves, a herald the arrival of spring. It also provides food for early pollinators, that would normally struggle to find food. It’s quite adaptable to various soil types and conditions.

2 Serviceberry (Amelanchier canadensis)

Another fantastic option is the Serviceberry (I have listed this already in my article about plants that feed the birds all winter), which can grow to heights of 15 to 25 feet. This small tree has beautiful white flowers in spring and produces small, edible berries that attract birds and other wildlife. Serviceberry trees are not only valuable for their beauty, but they also thrive in harsher conditions and contribute to soil stabilization. Their dense root systems help prevent erosion and that’s another good way to mitigate climate change’s impacts.

3 Field Maple (Acer campestre)

The Field Maple The Field Maple is the only maple tree that is native to the UK. They are popular for their attractive lobed leaves and beautiful yellow and orange autumn colours. The Field Maple is a relatively small tree, hardy one at that, often found in hedgerows and woodland edges. Reaches compact garden sizes, tolerates dry spells and high heat better than many maples, and provides food for local birds.

4 Crabapple (Malus spp.)

We do actually have a Crabapple in our garden. I normally try to use the apples in some way, while leaving some behind for the local wildlife visiting our garden. This year I made this apple butter with the apples, it was delicious. So, Crabapple is not just ornamental! Crabapple trees are fantastic for both, though: they have ornamental value and environmental benefits. These small trees typically grow to about 15 to 25 feet tall and will cheer you up with their stunning spring blossoms. Like I said, the apples also serve as a food source for various birds and mammals (and humans). Their ability to adapt to different soil types and resistance to many pests make them a low-maintenance option. They also very tough, we had such a hot summer in the UK this year, with draught and practcally no rain for months. In the UK! I know! But the Crabapple survived, whilst some other mature plants we lost.

5 Northern Espalier Pear (Pyrus communis)

For those interested in combining utility with beauty, the Northern Espalier Pear offers this opportunity. Typically trained against a wall or a trellis, this tree can be pruned to remain small and manageable, often around 6 to 10 feet at maturity. Not only does it produce delicious pears, but it also serves as a great cottage garden backdrop. 

6 Columnar Oak (Quercus robur ‘Fastigiata’)

This compact tree grows to about 30 feet tall but can be maintained at smaller heights with proper pruning. It offers an impressive canopy and supports wildlife including squirrels and birds. Oaks are known for their longevity and ability to sequester carbon. They are also tolerant of urban pollution.

7 Dwarf Alberta Spruce (Picea glauca ‘Conica’)

The Dwarf Alberta Spruce is a small evergreen conifer that typically reaches only about 10 feet tall. Its pyramidal shape provides year-round privacy and wind protection. As an evergreen, it continues to photosynthesize and sequester carbon dioxide year-round. This tree is particularly suited for spaces that need greenery in colder months.

8 Hazel (Corylus avellana)

We also have one of these, maybe we should plant more of this? Definitely something I am considering. Grows up to 10 meters, supports long-term carbon capture when managed or coppiced, and produces nutritious nuts. Hazel is a small, shrubby tree that can be found in a variety of habitats, such as woodlands, gardens and grasslands, which is why it’s excellent for UK gardens as well.

9 Juniper (Juniperus communis)

This is definitely on my list! Not that I’m going to start making gin! I just love juniper. It’s also an evergreen, which is a plus. Its hardy nature and year-round foliage allow it to absorb carbon at a steady pace, up to 10 metres. Because of its spikes, it can help keep small wildlife safe from garden predators like cats and the fruit is a favourite among birds. Juniper grows well in full sun and well-drained soil types.

10 Osier willow (Salix viminalis)

This tree is a stunner even in winter time with its yellow catkins! Not only useful but pretty as well. The osier willow grows fast and it can reach up to 7 metres. Also known as ‘basket willow’, its flexible branches can be used for weaving. So maybe you can even start making your own baskets Birds enjoy nesting among the branches and its catkins provide an important source of early nectar and pollen for pollinators.  

Tips to Care for Your Trees

To maximize the benefits of planting small trees for climate change, it’s essential to provide proper care. This includes:

Choose the Right Location

Plant the tree at a location where it gets enough sunlight and space to grow without overcrowding other plants. 

Soil Preparation

Use compost or organic fertilizers to improve soil health, it will help strong root development.

Watering

Newly planted trees require adequate water, especially in the first few years. Deep watering is essential for developing a strong root system. When the weather is unusually hot and dry for a prolonged period of time (like summer in the UK 2026), even established, mature trees need watering.

Mulching

Applying a layer of mulch around your tree can help retain moisture, suppress weeds, and improve soil health, this can be done once a year.