Will Any Plant Make A Hedge?
Before we go too far, we need to know what we want the hedge to achieve. i.e. to hide something, or to define a boundary. Then we need to know what size we want it to reach. Does it need to be deciduous or evergreen. Will it be there to discourage trespassers and have thorns. Do we need it to be a backdrop in order to show off other plants or architectural features? Does it need to be shade tolerant? If it is to be by a road, will it put up with salt spray in the winter? There may be many other specific considerations which may need to be taken into consideration, so take the time to think it through.
For the purposes of this blog, we’ll assume that our choice of species will come from the woody perennials, i.e. Trees and Shrubs, although this is not exclusively the case.
So, can we make a hedge from anything ? And what characteristics do we need from a plant in order to give us a ‘good’ hedge. And exactly what is it that defines what a hedge is?
So we’ll use the shrub Privet (Ligustrum) as an example, as it is extremely likely that most of us will already recognize Privet.
Growing in the wild from seed, (courtesy of a passing Bird), Privet will form quite a large rounded bush. It will be well furnished with branches, but compared with a hedge, it will be quite open in habit and will not form a ‘solid wall’ of twigs and foliage.
It will produce an abundance of white flowers, followed at the end of the summer by hoards of small black berries.
However, if we take one branch and cut it back, a number of dormant buds below the cut will spring into life, and where we once had only one shoot, we may now after a few weeks have as many as 4 or 5.
After they have been growing away for a few weeks so that they have several leaves growing along the length of each stem. If we then cut each of them back, we will end up with maybe 20 or more shoots starting to grow from what was that original one shoot. And all of this in a matter of a few short weeks, from one shoot to maybe twenty shoots.
And that is the characteristic that we are looking for that will allow us to create a tight density of growth which then can be formed into any shape that we like.
So it is the constant trimming back of the shoots in the growing season that gives us the finish that we want. It is also this same treatment in plants that produce their flowers on current seasons growth which renders the plant unable to reproduce itself. This is because the flower buds which would have developed in the season will no longer be able to. And as we know, no flowers, no fruit or berries. This is why flowers and berries can sometimes be seen on Privet hedges which have not been trimmed frequently.
There are many plants which don’t produce a tight pattern of growth and which are therefore not suitable for formal hedging. There are also plants which have a tendency to thin at the base after a few years, or which are not hardy in the more northern reached of the British Isles, thus rendering them ineffective in many situations. There are even plants which are not that long lived and which could die off just as they begin to be effective, so great care still needs to be taken, and we need to guard against that.