How to Grow a Hedge
No matter how beautiful a garden is, it looks incomplete without a hedge. A hedge is necessary for a garden, not only to make it look complete, but also for maintaining the privacy of the owner, reduce outside noises, and protect the garden and people inside from strong winds and snow. Rather than concrete walls, a hedge offers the sense of life and its greenery pleases one’s eyes and mind.
However, people wrongly think that growing a hedge might be a complicated process and hence, try to avoid it. But in reality, it’s a quite simple task and can even be quick with the right steps. One just has to select a species of plants to suit their needs, collect enough plants for the desired length of the hedge, amend the soil, dig holes or trench and plant the green fence.
Although it may take around 3 to 5 years to fully grow, once it grows, one just has to water it regularly and maintain the plants, and they’ll keep growing and form a good, dense hedge.
Published: June 8, 2021.
What is a Hedge?
Known also as a green fence, living fence, or hedgerow, a hedge is a fence that borders a garden or keeps two parts of the garden separate from each other. It can be grown by planting bushes, shrubs, or short trees close to each other.
Benefits of a Hedge
- Blocks outside noise
- Protection from wind and snow
- Keeps children and pets safe within the property
- Adds beauty to the garden
- Birds can build nests in the hedge
How to Grow a Hedge?
Different gardeners may have different purposes behind growing a hedge. However, if it’s to be grown on the borders, protection, and privacy can be common purposes for most gardeners. Depending upon the purposes and other factors, the gardener can plan to grow a hedge.
Researching about Regulations
Even before starting to prepare to set a hedge, the first and foremost thing a gardener should do is to check the regulations of their town or municipality about hedges. They should check if they require a permit for installing/growing a hedge and if there are any ordinances about hedges that don’t interfere with pedestrian traffic or hinder motorists’ visibility.
While determining the location and width of the hedge, the gardener should also consider if the hedge plants will encroach upon their neighbors’ property or any public property, and choose the hedge plants and location so as to avoid any future problems.
Considering the Cost
Once the gardener finds about the regulations about hedges and any social concerns and plans to set a hedge abiding by them, the next important thing to consider is the cost. They should set a budget and plan a hedge that will suit their budget.
Determining the Location of the Hedge
Determining the location of the hedge is an important factor because a living fence set up in the wrong location can suffer from breakages from humans and animals, and stunted growth.
Professional landscapers suggest that the right locations for a hedge are edges and boundaries. However, one can choose other places too provided that it doesn’t affect people’s movements or hinder them from performing other gardening tasks.
When to Plant a Hedge
Fall is by far a perfect time to plant a hedge, i.e. after the hedges are dormant. But fast-growing hedge plants can also be planted through the winter if the ground in the gardener’s area doesn’t freeze hard. Even spring is a good planting time.
Choosing Plants for the Hedge
Gardeners should remember that they can choose various types of plants including bushes, vines, shrubs, or trees. They can even choose to combine these various types rather than growing only one type of plant.
For year-round protection and privacy, choosing evergreen plants for the hedge is a good idea. They keep growing throughout the year and look full. Gardeners should look for evergreen plants that can grow well in their area; otherwise, the hedge may not look full. Examples of evergreen hedge plants are Boxwood, Glossy Abelia, Dwarf Golden False Cypress, Juniper, Variegated False Holly, Japanese Pittosporum, Hybrid Yew, Mahonia, and Arborvitae.
If they want to grow an impenetrable fence, they should choose thorny species such as Blackthorn, Prickly Ash, Honey Locust, Pyracanthas, Jujube, Hollies, Rugosa Rose, and Hawthorns.
For a multifunctional fence, the gardener will have to combine various types of plants. Such a multifunctional hedge should contain high as well as low-growing plants.
One can even choose evergreen flowering shrubs to create a hedge so as to add more colors to their green fence. Examples are Glossy Abelia, Flowering Quince, Oleander, Scarlet Firethorn, Korean Lilac, Spirea, and Shrub Rose. Shrubs like Arrow-wood Viburnum, Scarlet Firethorn, and Holly even produce tiny colorful berries that add to the beauty of the hedge.
Deciduous plants too look beautiful with their bright blossoms in spring and summer; but since they shed leaves in the cold season, they can’t provide safety all through the year. Still one can choose deciduous plants like Western Red Cedar, Hornbeam, Lilacs, Forsythia, Rosa Rugosa, Quince, Weigela, Flame Amur Maple, and Portuguese Laurel for their hedge. Certain deciduous plants even have thorns on them; thus they can provide protection against big animals like deer.
Although the above points are important, it’s also important to choose plants that are easy to work with, resistant to pests and diseases and drought, and easy to propagate. Some examples are Osage Orange, Beech, and Leylandii.
On the other hand, plants like Privet, Autumn Olive, Burning Bush, and Japanese Barberry are considered invasive as they can quickly grow out of control if the gardener cannot maintain them properly. Hence one should avoid them if they are not confident of maintenance. However, if one is confident of controlling their growth, Privet is an excellent plant for a hedge because they grow fast to form a hedge in less than 2 months.
They are evergreen and provide perfect privacy, security as well as beauty. Moreover, they can grow virtually in any type of soil and require less maintenance.
Height of Plants
Gardeners should think about the height of their plants and whether it matches the height they desire for their hedge.
Some shrubs can even reach a height of up to 15 feet (4.6 meters). Examples are Juniper, Arborvitae, and Photinia. Although they will provide a higher amount of protection, they will take more time to prune and maintain.
Therefore it’s better to decide on what height of the hedge shrubs one wants so as to be easy to maintain and then check the maximum height the shrubs grow up to and choose only those that grow up to one’s desired height. Thus, shrubs that grow up to 2-3 feet (0.61 to 0.91 m) are perfect for those who want just a small green wall, and also for a hedge inside a garden to segregate any two of its parts.
Shrubs like Weigela, Boxwood, and Forsythia grow up to 3 to 5 feet (91 to 152 cm). Shrubs that grow up to 4-6 feet (1.2 to 1.8 m) are perfect for those who want more privacy and protection. If one chooses shrubs that grow more than this height, they should maintain the shrubs at eye level so that they won’t have to use a ladder to trim them.
However, if one is ready to maintain their hedge plants using ladders, some high plants are:
- American Arborvitae that grows up to 40 to 60 feet (12.2 to 18.3 meters)
- Green Giant Arborvitae that grows up to 60 feet (18.3 meters)
- Nigra Arborvitae that grows up to 20 to 30 feet (6 to 9 meters)
- Emerald Arborvitae that grows up to 10 to 15 feet (3 to 4.6 meters)
Note: One should also make sure they comply with the hedge height rules of their city or municipal council.
How Much Should be the Space between Plants?
Of course, to grow a thick hedge, the space between the plants should be narrow. However, one should consider the species used to create the hedge. If the particular plants are going to grow wide at maturity, the gardener has to keep a wide spacing between the plants.
Seeds, Seedlings, Root Sprouts, or Cuttings?
One can use seeds, seedlings, root sprouts, or cuttings of plants to grow a hedge. Seedlings and root sprouts are used most commonly. In general, seedlings that have developed roots are easier to grow than seeds. However, one can use even seeds and even plant cuttings.
How Many Plants?
Ideally, for a hedge, the gardener should buy 1 plant for every 3 to 4 feet (0.91 to 1.22 m). They can find this out by dividing the desired length of the hedge by 3 feet (0.91 m) and make it a round figure. This will be the number of shrubs they need.
How to Start Planting?
Digging Holes or a Trench
To make sure, the row of the hedge is straight and the spacing between the plants is correct, the gardener can use wooden stakes tied together with a string keeping the desired gap between each two of them and place the string at the desired location of the hedge. Then a sprinkler flag or other marker can be placed along the string.
For planting the shrubs, there are two methods, individual holes or a trench.
Now the gardener should dig holes or a trench for planting the shrubs. For this, they should first measure the heights and diameters of the root balls of each shrub, because the width of the holes or trench should be double and depth should be the same as that of the root ball of the shrubs. In the case of a trench, the width should be double and the depth should be the same as that of the largest shrub.
In the case of holes, the gap between every 2 holes should be at least 3-4 feet. In the case of a trench, the gardener can dig the trench using a shovel, trench digger, or mini-excavator. The latter 2 will do the job more quickly.
Gardeners can also consider making double or triple rows of hedges and dig trenches accordingly. In that case, the number of plants should also be more. The gardener should even choose plants that grow short for the inner row and those that grow high for the outer row.
Now the gardener should amend the soil a bit by mixing manure and compost with the soil dug out while forming the trench. Every 2 parts of soil should be mixed with 1 part of manure and 1 part of the compost. Gardeners can even use homemade compost.
To handle the plants, if the gardener is using seedlings, they will either have to pull them out from their pots or cut the burlap around the roots.
They can even use a hand cultivator which is a metal claw with which one can break the soil apart around the roots without damaging them. But the gardener is better off not removing all the soil; otherwise, the plant can be damaged. If the gardener doesn’t have a hand cultivator or doesn’t want to use one, they can even remove the soil by hand. They should use garden gloves while working though, so as to avoid the risk of any irritation or infection.
Now the gardener should set the plants in the holes or trench with a gap of 3-4 feet between them. The first shrub in the trench should be around 1 ½ - 2 feet away from the end wall of the trench to give it a space for expansion. Then the gardener should go on planting the shrubs 3-4 feet away from the previous one.
Keeping a gap less than 3-4 feet will cause the shrubs to compete with each other for water and nutrients, and they won’t even grow properly. So, gardeners should remember to keep this much gap.
Once the plants are set into the holes or trench, the gardener should backfill the soil to form small mounds at the base of the shrubs
Note: If the gardener is using seeds as planting materials, they should place them in the holes or trench, and cover them with soil. If they are using cuttings, they should insert them in the holes and cover them partially with soil. Root sprouts are to be transplanted in the holes or trench.
Now the gardener should water the plants until the soil becomes wet to the depth of 1 inch (2.5 cm). They should pour the water as close to the roots as possible so that roots can easily absorb it.
Ideally, the gardener should poke their finger into the soil up to the first knuckle to check if it’s properly wet. If the soil isn’t wet, they should pour more water. For watering the plants, a sprinkler, a sprayer attached to a garden hose, or a watering can be used, but a jet attached to the hose should be avoided as it can damage the plants and disturb the soil with the force of water.
Now the gardener should spread a 2-3 inch (5 – 7.5 cm) layer of mulch around the trunks of the bushes. The mulch can be spread evenly using a rake. However, gardeners should not let the mulch touch the bushes’ trunks; otherwise, there could be root rot. Mulch keeps the soil evenly moist and prevents the growth of weeds.
Taking Care of the Hedge
After the initial watering, the gardener should water the bushes once a week until the soil is totally saturated. The water should be poured as near the roots as possible.
If the gardener’s area receives heavy rains during the week, the gardener need not water the hedge.
A drip irrigation system can be used to water the hedges instead of manual watering.
Once the hedge sets its roots deep in the ground over several years, the plants will need very little supplemental water. However, the gardener should provide adequate water to the plants during the first 1 or 2 growing seasons after planting.
The gardener should prune their hedge in late winter so as to make them narrower at the top. They should prune the plants after any buds or flowers become brown so as to avoid removing any healthy growths. While pruning, the gardener should make sure the top of the hedge should become narrower than the base because the branches at the base should also get sunlight.
While pruning the branches inside the hedge, the gardener should reach the middle of the hedge and grab 1-2 branches and clip every 2-3 feet (0.6 – 0.9 m) of them. A pair of hand pruners should be used for this purpose and branches should be cut at a 45° angle. Then the gardener should move around 2 feet down the hedge and cut 1-2 more inner branches.
Cutting the inner branches in this way allows improved airflow and sunlight to reach the inner side of the hedge. Gardeners should remember to wear gardening gloves and other appropriate protection if the hedge is made of thorny plants.
They should remember to keep the hedge at least 3 feet (0.91 m) thick so as to be healthy and have proper growth. Also, the hedge should not be thinner than 1 foot.
Inosculation: Inosculation is a process in which two or more branches are joined to grow as one branch. This can be done while pruning the hedge.
Training the Shrubs as a Hedge
It takes around 3 to 5 years for the shrubs to grow fully and form a thick hedge. This process can be sped up and the gardener can encourage their plants to grow vigorously. To train them as a hedge, the gardener should prune their tops and sides a few times every year as required, and remove around ½ the length of the new shoots.
Most needled evergreens grow early in the season, whereas most deciduous plants and broadleaf evergreens take longer. Ideally, the hedge should be wider at the base than the top, as mentioned above, to let the lower leaves get sunlight.
Trees like Pine, Cedar, and Juniper should be excluded though from training as a hedge and allowed to grow naturally.
It’s necessary to support weak plants if there are any with stakes. However, by far staking helps plants grow upright and promotes a fuller and uniform hedge. For staking, the gardener will need small wooden posts (stakes) and wires or strings. If the hedge is wider, they may even need small rails to support all rows.
Now the gardener should insert the stakes near the bushes and tie wires or strings on and around them to create a supportive structure. For additional support, the gardener can fix the rails on the posts with wires or small nails.
Weeds compete with the hedge for water and nutrients, and hence gardeners should make sure to prevent weeds from thriving around their hedge. Weeding tools can be used to remove them. Or they can be uprooted by hand or killed with an herbicide.
The gardener should apply a 10-10-10 granular fertilizer every spring around the hedges. They should pour the recommended amount of fertilizer around the base of the plants. Then they should water the hedge right after that so that the fertilizer can get soaked in the soil and nutrients can be easily available for the plants. The fertilizer should never be let touch the trunks of the plants otherwise it can damage them.
As the mulch decomposes, it releases nutrients and organic matter into the soil, feeding the plants.
Organic fertilizer releases the nutrients slowly and feeds the hedge over a longer period of time - exact amounts vary depending on the type of hedge plant, soil quality, and type of organic fertilizer.
Prevention of Pests and Diseases
Just like other plants in the garden, the plants in the hedge too can be attacked by pests like spider mites, scale insects, and aphids, and diseases like box blight, powdery mildew, and bacterial canker.
The gardener should keep an eye on the plants to catch such attacks on time and cure them. They should regularly check the plants for any signs. For example, they should check the leaves to see if there are any stains, holes, scales, or bites on them. Especially, the underside of leaves should be checked keenly, as bugs lay eggs normally on the underside of leaves. If the infestation or infection is severe, the affected plant/s should be removed to prevent further spread.
In case if the gardener notices any pests, they should spray a commercial organic pesticide to get rid of them.
Also, gardeners should regularly remove dead branches and yellowed or withered leaves.
If the gardener is not sure about the problem, they should take the help of their local garden center to diagnose and treat the same.
Here’s how to deal with some common pests and diseases:
Spider Mites: A number of species of these small sap-sucking insects can affect the hedge plants. As such, they mostly occur in greenhouses. But in warm and dry summers, they affect even outdoor plants and especially box hedging. Their presence can be identified by pale smears on the upper surface of leaves and several tiny yellow-greenish mites and eggshells on the underside.
A magnifying lens can show their presence more clearly. In severe cases, fine silky webs are seen on plants and leaves lose most of their green color.
Spider mites may not be a big problem for outdoor plants; however, as they affect young growths, those growths should be regularly clipped and then burned.
Scale Insects: This too is a sap-sucking insect having a protective shell-like scale on its body. A number of species can affect hedging. Their presence is marked by small bumps occurring underneath leaves or on stems. Some of the species secrete a sticky white cover to protect their eggs in summer.
Infested woody stems can be washed with warm, soapy water and a brush. Products containing Cypermethrin or Deltamethrin are also effective. These should be sprayed in May/June. Gardeners should follow the instructions on the products’ labels.
Aphids: By far, aphids are the most common pests on hedge plants and they have several species. These too suck the sap of plants. They are about 3 mm long, green, black, and many other colors, and usually attack the soft young growing tips in spring and summer. They may even have a woolly protective cover.
Gardeners can see the infestations of young growing tips with the naked eye, usually along with twisting of young growths and overall weakened plants. Aphids also secrete a sticky honeydew which causes the growth of black sooty molds (not harmful to the plants).
Aphids can be naturally controlled by predators like ladybirds and hoverfly larvae. The gardener can even wipe off small infestations with a wet cloth.
Several pesticides are available to control aphids in hedges. Those containing Cypermethrin or Deltamethrin are the most effective. Instructions on the labels should be followed strictly.
Box Blight: Box blights affect box hedging and sometimes also known as boxwood blight. It’s caused by two strains of fungi, which remain dormant in dead leaves and form spores as temperature increases through spring.
One of them, Cylindrocladium buxicola, is marked by spots on leaves as well as thin gray fungus growing underneath the leaves and black stains on woody parts. Over time, these become larger and cause defoliation.
The other strain is Volutella buxi which causes pink pustules on the underside of leaves, usually in humid weather. It can cause yellow leaves that fall off and sometimes the development of cankers on branches.
Since these fungi remain dormant in dead leaves, burning the dead leaves and disposing of other affected material is a solution.
A garden chemical is not available to treat any of these strains, but copper fungicides have some effect. However, prevention is perhaps the best solution. The gardener should plant the hedge in good organic soil with a layering of fish and bone on the top, and spray a fungicide in early April.
This is particularly effective if the gardener avoids clipping their hedge in warm, humid weather since the fungi are most active in damp conditions.
Powdery Mildew: This appears as a gray powder. It’s a fungus affecting various hedging plants. Unfortunately, most plants are not immune to this infection. But fortunately, it’s quite easy to treat.
The gardener can just spray a fungicide or simply do nothing, and it will go if the underlying cause is removed. An underlying cause is dry plants and this can be treated by watering, especially in hot weather.
Another long-term solution is to add more amount of well-rotted organic matter to the soil which enables the soil to hold more water and reduce the stress of plants during dry climates.
Still another easy solution is to spread grass clippings at the bottom of the hedge plants.
Powdery mildew can also spread due to poor air circulation around the plants, which happens especially due to thick hedging and sheltered climbing plants. In that case, the gardener should spray a fungicide or prune the overgrown parts of the plants.
Bacterial Canker (Pseudomonas syringae): This is a waterborne disease and affects plants in Prunus species. However, Prunus lusitanica (Portuguese Laurel) and Prunus laurocerasus (Cherry Laurel) varieties are more resistant than any other Prunus species.
The disease is characterized by small brown patches that occur on leaves from midsummer. Centers of the leaves fall out forming a small round hole; that’s why this disease is also called shothole disease. Branches are marked by sunken lesions or dead areas, usually along with a sticky yellowish-brown secretion. The lesions even cut off the sap flow in severe cases resulting in the death of the entire branch.
The bacteria are waterborne and enter leaves through stomata i.e. breathing holes. The gardener should restrict the pruning of Prunus species to July and August as the plants are most resistant during this period. Also, they should apply a sealant containing copper on the pruning wounds. So far no chemical is available to control this disease.
Protection from Animals
A hedge is always in danger from herbivores. But even pets like cats and dogs may destroy the green fence. Therefore, the gardener should protect the hedge from animals.
A great solution to this is to install wire fencing around it initially. Once the hedge grows strong enough to repel animals, the wire fencing can be removed.
Long Story Short: All in all, growing a hedge is not complicated and a gardener should grow one in order to add more greenery and colors to their garden and have privacy and protection. Just like growing other garden plants, growing a hedge is also a fun process and gardeners should enjoy it thoroughly.