We all know that planting trees is a crucial strategy for fighting climate change and boosting biodiversity. Many will choose to purchase saplings or young trees to plant in their gardens. But you might also consider taking the time and effort to grow native trees from seed.
Growing native trees from seed obviously takes more time and effort. But if you love to garden, and want to do your bit to enhance the ecology in your area and safeguard the future, sowing seeds from native trees can be a wonderful thing to do.
Choosing Which Native Trees to Grow
Of course, if you would like to grow native trees from seed, the first thing you will have to think about is which native trees you would like to grow. You might grow them for your own garden, or perhaps even to help with conservation efforts or ecosystem restoration in your local area.
Large Native Trees
- Birch (Silver)
- Limes (Small-leaved, large-leaved)
- Oaks (English, Sessile)
- Pine (Scot’s pine native in Scotland)
- Poplar (Black)
- Willows (White, crack)
Medium-Sized Native Trees
- Birch (Downy)
- Cherry (Wild, bird)
- Wild Service Tree
- Willows (goat, bay)
- Acer (field maple)
- Alder buckthorn
- Crab Apple
- Plymouth Pear
- Willows (grey, osier)
Great Hedgerow Species
Of course, a number of the above also work well, along with further shrubs, in hedgerow planting schemes.
It is important to choose trees suited to the environment, and to the space available.
As well as native trees like those mentioned above, you might also consider sowing seeds from naturalised species, such as the horse chestnut, common chestnut, and Amelanchier, for example.
Gathering Seeds From Native Trees
The first stage, of course, will be identifying native trees. Learning more about plants and plant identification is a wonderful step to take as a gardener, and as someone who wants to help protect and preserve the natural world.
It is important to collect seeds at the right time. If you collect too early, the seeds may not be fully developed. You may affect the ability of the seed to germinate. If you wait too long, the seeds might be taken by the wind or the local wildlife.
While sometimes seeds can sometimes carefully be collected from the trees by hand, often, the best option to propagate many native trees from seed is to collect the seeds from the ground as soon as they fall. Just remember that you should never take all, and should leave plenty for natural germination and wildlife.
Preparing Seeds for Sowing
There are several key groups of seeds produced by native trees, which are processed in different ways:
- Fruits or berries – processed by popping, mashing or pulping and straining them to extract the seeds.
- Nuts – (e.g. hazel) may be removed from husks to check viability with a float test but are often just planted.
- Wings – removed from stalks/twigs then planted. (Some, such as ash keys, will not germinate until the second spring).
- Cones/Bracts – (e.g. alder, birch) – collected just as cones or bracts begin to turn from green to brown. Place in a paper bag to dry and seeds are released.
Most of our native tree seeds are dormant and require some kind of treatment before they will grow. This is simple enough to achieve by providing a period of cold and/or warmth, which nature will provide if seeds are stored outside for the right length of time.
Seeds which have no dormancy (aspen, oak, willow, wych elm for example) should be sown right away.
Some are best stored dry and pre-treated in spring. (e.g. Alder, birch)
Some should be pre-treated and sown the fist spring after collection. (Cherries, crab apple, elder, hazel, rowan etc..)
And some are pre-treated and then sown the second spring after collection. (Ash, hawthorn, holly, yew…).
Sowing Native Tree Seeds
- If you are only planting a small number of seeds, container growing should work well. Prepare a pot with good drainage and fill it with a suitable growing medium (50% leaf mould or peat-free compost and 50% grit/sand.)
- If you are sowing a larger number of trees, prepare a seed bed top dressed with plenty of organic matter.
- Water so that the medium is moist but does not drip more than a drop or two of water when gently squeezed.
- Plant seeds around twice their own depth, firming the medium gently over and around them. (Plant several seeds to increase chances of success in germination.)
- As a general rule, the larger the seed the higher the germination rate tends to be.
- Place the pot in a cool and shaded spot, covered with wire mesh where wildlife may get to the seeds.
- Check one a week or so to make sure the soil has not dried out, and water when required. But take care not to overwater.
- When the seeds start to sprout in spring, keep an eye on growth and repot into larger pots as required.
- Watering with a balanced, organic, liquid plant feed from when the first true leaves appear until the end of July can help improve results.
- Once the tree seedling reaches around 40cm tall, it can be transferred to it final position in the ground.
Planting Native Trees
Our tree planting tips for gardeners should help you make sure that you plant correctly, and get your native trees off to the best possible start.
Growing native trees from seed does take time and effort. But by sowing these seeds you can help propagate vital tree species, and play a role in maintaining and restoring native woodlands and forests. There is a lot to learn about sowing and growing specific tree species, but the guidelines above should help guide you as you take the first steps and, perhaps, give it a go.
Elizabeth Waddington is a writer and green living consultant living in Scotland. Permaculture and sustainability are at the heart of everything she does, from designing gardens and farms around the world, to inspiring and facilitating positive change for small companies and individuals.
She also works on her own property, where she grows fruit and vegetables, keeps chickens and is working on the eco-renovation of an old stone barn.
To get in touch, visit https://ewspconsultancy.com.