Plant, Grow and Nurture your oaks

As a lover of trees, I am always inspired to visit a tree of any species or size that has some special, character or story to it, but more especially a heritage tree. Heritage trees are large trees with unique value, usually large, old or rare with a high historic, botanic or ecological value and often beautiful works of natural art. Many of our heritage trees are ancient oaks; trees over 400 years old, which are mere teenagers of the tree world as our English oaks can live to be well over a thousand years old where they are growing in the perfect conditions with some form of protection like the “Majesty Oak” in Fredville Park, Kent. These trees are very special, with more ancient oaks in our landscape in England than the whole of the rest of Europe.

Tony Kirkham and The Majesty Oak

For me and many others, we love to see an ancient oak growing in any of our woodlands, parks, gardens or historic landscapes, guessing their age, wondering what they have seen, heard and witnessed as they have grown over time. They are historical living timelines! This always makes it a wrench for me to leave them, wondering if there is anything on the tree that I have missed or when will I be back to see it again, and let’s have another photograph together. This feeling is good for our mental health and wellbeing and must not be underestimated.

There are over 500 species of oaks growing in the temperate forests of the world, but in the British Isles we only have two species of native oaks, the pedunculate oak (Quercus robur), and the sessile oak (Quercus petraea) and hybrids between the two (Quercus x rosacea). These are special trees in our landscape with the social and environmental value of oak woodlands in Great Britain estimated at £320 million per year. This reflects the many benefits that they provide to our eco system services such as improving air and water quality, carbon sequestration, reducing air temperatures by providing shade from the broad canopies, absorbing heavy rainfall reducing water run-off and preventing erosion. As well as our mental wellbeing oaks also have a huge biodiversity value. They are living tower blocks to 2,300 species of living organisms, which include fungi, mosses, ferns, invertebrates, birds and mammals using our native oaks with 326 being obligate (only found on our native oaks). Imagine a landscape without our oaks!

Seeing an old oak is a good feeling but planting one and watching it grow is even better and far more rewarding so why not have a go and plant one. It’s easier than you think.

Why not start by growing your own tree from an acorn that you have collected on that walk in the park or countryside. The number of acorns produced by an oak tree vary from year to year with the occasional “mast” year where there is a bumper crop of acorns. It is believed that this natural process occurs to provide enough food to feed predating mammals and birds, leaving enough to germinate and grow into new seedlings allowing for species survival. Even when there isn’t a “mast” year, if you look closely there will be the odd acorn on the tree or on the ground which can be used to start the growing process at home. They can be a fresh green colour or when fully ripe they will turn a nutty-brown and the acorn at both stages can be sown.

Take a small plant pot and fill it with peat-free compost and push the acorn with the pointed end upwards into the compost with the top of the acorn just under the surface. The pot can then be placed outdoors with some protection over the pot, as squirrels and mice are very smart at finding these and will dig them up, often burying them elsewhere as a part of the winter cache.

The pot with the acorn should be left through the winter and ignored as the acorn will send out a young root called a radicle to anchor it in the soil and go to sleep. The following spring as the weather improves the acorn will produce a young shoot above the compost called a plumule which is the start of this oak tree’s new life.

Now you will need to water and nurture the new tree as it develops a stem with leaves and a root system in the plant pot. Depending on the weather and the tree, it can make a plantable size at the end of the first year, or it can be re-potted into a larger pot and grown for another year making it a sizable transplant.

I prefer to plant a tree in the autumn, which allows the tree to part establish before the following spring, giving the tree a good start, but the tree can be planted in the winter or spring, depending on the weather conditions. We shouldn’t plant trees in frosty weather or when there is snow on the ground.

There is so much useful information in books and on the internet that will help to ensure the tree is planted correctly, but a few good tips include: dig a square planting hole, not a round one, use the soil that comes out as backfill and don’t add compost or fertiliser, plant the tree at the depth that it is in the pot or the nursery mark where the roots join the trunk if you buy a tree; do not plant the tree any deeper as this will eventually kill it. Mulch the soil surface with woodchips, bark or compost, keeping it away from the base of the stem/trunk to prevent the soil drying out and to eliminate competitive weed growth for a young tree. Provide some form of protection from grazing deer or rabbits, like wire mesh or a tree guard and water it during dry periods.

Tony Kirkham with a newly planted oak sapling.

Remember to plant the tree in the right place in your garden or seek permission to plant it in the local park or landscape and enjoy watching it grow. We need more oaks in our landscape and Action Oak is leading the vital work and research to protect our native oak trees and safeguard their future.

 Tony Kirkham