Spring feels like the ideal time to put down new roots and plant trees in your garden. But if you are considering planting bare root trees this year, then get them in quick, as the planting season will soon be over. Thankfully, celebrated gardener Monty Don has the definitive advice for planting bare root trees, so there’s no need to delay.
See: Monty Don reveals the benefits of planting bare root roses
As their name suggests, bare root trees have no soil at their roots, and have been dug up from the ground while dormant. They might look barren in their inactive state, but will soon spring back to life after planting.
They have several benefits over potted trees, too. ‘Bare root trees tend to be cheaper and better quality,’ says Don in his book The Complete Gardener (opens in new tab).
- See: How to grow tomatoes - the best ways to grow your own tomato plants
Traditionally the season for planting bare root trees starts in the fall and extends well into April, but it’s risky to leave planting until the last minute, as once the weather warms up and plants come into full leaf, it’s too late.
Alternatively, potted trees can be planted at any time, but will need less watering if done in fall or winter.
Don offers a helpful demonstration of his expert planting technique on a bare root hornbeam in an episode of BBC’s Gardener’s World (opens in new tab) – though the advice is the same for any tree species.
He reveals that the first rule of planting bare root trees, is never to expose their roots to the air – ‘because literally within a minute they’ll start to dry out'.
See: Monty Don's tips on getting the perfect lawn
Don adds to this in The Complete Gardener, explaining that he uses a soaked hessian sack to cover the roots and, before planting, soaks them in water for at least 10 minutes.
While your tree is soaking, you can get on with digging the hole. ‘A big mistake when you’re planting trees is to bury them too deep,’ he says in his demonstration, advising to dig ‘a wide hole, but not a deep one’. Aim for roughly twice the spread of the roots, and around a spade’s depth.
Don also warns against forking up the earth underneath where the tree will sit – and never adds manure to the hole. ‘What happens is, the compost or manure collapses down, the hole settles and you get this sump – and then all the moisture goes in, it collapses down and will drown,’ he explains.
Instead of digging over the ground, he just uses his fork to ‘tease’ the soil, lightly loosening the bottom and sides of the hole so that there’s some drainage. He also removes stones, which can impede the roots.
When you are ready to plant your tree, gently place it into the hole and spread the roots out over the soil. ‘Immediately fill round the roots with top soil, and as you do so just lift it slightly and shake it, because we want to work it into all the crevices,’ says Don.
Next, holding the tree in position, he firms it down from the outside using his heel, taking care not to bury the stem at all – ‘because we want it to sit on a little cone’, he says.
See: Thriller, spiller, filler – the gardening experts' secret for creating show-stopping containers
Don expands on the concept of creating a 'cone' in The Complete Gardener, explaining that ‘trees planted on a slight mound develop much deeper, wider and stronger root systems than those planted in a slight basin, so they are much less likely to be blown over by strong winds.’
He recommends staking trees for around three years, showing his technique in his video. He adds the stake at 45° into the wind – ‘it could be nice and low' – and ties it securely.
Finally, whatever the weather, Don advises to give the tree a really good soak, then follow with mulching. ‘Now this is where you do put your organic material – not under the roots, but above them. Give it a really good mulch.’ This will suppress competition from weeds and grass.
Maintain your tree by watering monthly for the first year or so, pruning in the dormant season, and mulching annually in the spring.