If you have just bought a polytunnel, you may already have plenty of great ideas about layout and design. You may already be planning all the great things you can grow inside. One important decision that you will have to make is what you will use for garden bed edging.
One of the first things to decide is whether you will have raised beds in your polytunnel, or garden in the ground. This will, of course, determine whether raised edging will be required. The height at which you would like your growing areas will determine how high edging should be built. Once you have decided this, you will have to decide which material or materials to choose for the edging you require.
In order to make your polytunnel as sustainable as possible, it is a good idea to choose garden bed edging that is made from natural or reclaimed materials. These top bed edging ideas for your polytunnel should help you to make a good choice:
Natural Garden Bed Edging Materials
Natural materials are often readily available. You may decide to buy bed edging. But you can also relatively easily make your own, perhaps even with free materials from your very own garden. You may also be able to source natural materials from your surrounding area. Here are some natural garden bed edging materials to consider:
Living Plant Bed Edging: You might not need to create hard edging for your growing areas at all. Plants can also serve to form a boundary between your main growing areas and your pathways. For example, you could use lavender, thyme, or other spreading perennial herbs to make your edging. You could also edge beds with other plants, like strawberries, for example.
For more formal division, you may also be able to consider growing box or another form of low hedging, or even using step-over apple trees or other shaped fruit trees to define a space.
Natural Wooden Bed Edging: Wooden bed edging of some kind or another is, perhaps, the most popular choice for a polytunnel. Rather than buying new wood for such a project, however, consider using natural wood from the local area instead.
Natural wooden edging usually takes the form of logs. Logs can be placed horizontally on the ground, stacked like a log cabin for raised beds. You can also stand them vertically in the soil to create edging to a range of different heights.
Other types of natural bed edging to consider are fence-type edging ideas. For example, you could make a mini wattle fence to form low edging around in-ground growing areas, or higher ones around raised beds. Making wattle fence edging around your growing areas using branches pruned from garden trees could be another good, sustainable choice.
Natural Stone Bed Edging: Natural stone, either cut formally for wall building, or in the form of natural rocks, or rounded river rocks can all be great bed edging choices. One of the benefits of lining your growing areas or building up raised beds with rocks is that they have excellent thermal mass. They store the sun’s heat during the day and release it slowly when temperatures fall. So they can help keep your polytunnel at a more constant temperature.
Stone can also be an attractive choice. Rocks come in a range of shapes and sizes. They can be placed in a line around ground level growing areas, dry stacked, or mortared into position. So you can use stone to create a wide range of effects that can fit in with a wide range of garden styles.
Clay/ Cob Bed Edging: Another material that can be great for thermal mass and for edging raised beds is cob. Natural clay and other materials like straw can be used to build up low walls around the edges of your growing areas. Cob can be used as a stand-alone material for building bed edging. Or you could also consider creating a ‘daub’ to make low wattle and daub structures around your polytunnel beds.
Trench Garden Edging: If you are growing in the ground in your polytunnel, you may not need to build up raised edging at all. Another way to separate your paths from your growing areas is to dig a shallow trench, and fill it with natural materials.
If your polytunnel is in a spot prone to waterlogging, such trenches can serve an additional function, to drain water out of the area. Trenches could also be designed as irrigation ditches to channel rainwater to where it is most needed inside your tunnel.
You could fill a garden trench with gravel. But you could also consider using natural pebbles from your garden, pieces of natural slate, or even more unusual collected materials like shells.
Shells or pebbles could also be inset into clay to form decorative in-ground bed edging.
Reclaimed Garden Bed Edging Materials
In addition to considering the options that would allow you to use natural materials for bed edging, you should also consider using reclaimed materials. There are a huge range of ways to repurpose, recycle or upcycle old materials to give them new life in your polytunnel. Here are a few of the best examples:
Reclaimed Wood Bed Edging: There are a wide range of ways to use old wood for edging your polytunnel beds. You might be able to reclaim wood from building projects or old furniture. Wood pallets can be another good source for reclaimed timber. (But be careful. Make sure you know where they came from, and that they have not been treated with or exposed to harmful chemicals.)
You could build up bed edging with planks of reclaimed wood, or build a low fence made of the material.
Reclaimed Brick Bed Edging: If you want something more enduring than wood, and something with better thermal mass, old bricks could be a good choice. By using old bricks in your polytunnel, you can prevent them from ending up in landfill.
You can use bricks to make a low mortared wall for raised beds, or simply place a row of bricks around the edges of a growing area. You could also consider creating a decorative effect by placing rows of bricks next to one another in the ground, or bury them sticking up from the ground at an angle.
Reclaimed Concrete Bed Edging: Building bed edging from concrete is popular in modern gardens. But new concrete comes with a high carbon cost. So rather than using new concrete to pour bed edging, or buying new concrete blocks or breeze blocks, considering using reclaimed concrete instead.
Concrete is another material with good thermal mass. And breeze blocks could also be positioned so that the holes in the centres could be planted up and provide additional growing area.
Upcycled Metal Bed Edging: There are also a wide range of ways to create a range of decorative effects by using reclaimed metal in various shapes and forms. Old metal sheeting, or corrugated metal, for example, could be used to form the sides of raised beds. You could also potentially use old metal piping placed vertically to create bed edging.
Other quirky ideas include using metal wheel rims to form a low fence between your paths and growing areas. You could also make gabions (filled with rocks or other materials) from fencing wire or chicken wire to make your bed edging. Gabions could potential double as bed edging and seating in your polytunnel.
Ceramic Materials Bed Edging: Other interesting ideas include using ceramic tiles or even old plates to form a low boundary between paths and polytunnel beds. You could also use ceramic chimney pots or piping placed vertically in the ground to line your growing areas. These could also be planted up with companion plants. You could also consider laying a row of old ceramic plant pots on edge to form the bed edging. Or create in-ground edging by making a mosaic from broken tiles etc..
Glass Bottle Bed Edging: One final idea to consider is using household waste to make your garden bed edging. One popular idea simply involves inserting a row of glass bottles upside down in the ground. You could also consider stacking bottles on their sides to create low walls.
These are just a few ideas for garden bed edging that should help you plan how to separate and define the various growing areas in your polytunnel. Do you have your own ideas or suggestions to share? Please do so in the comments below.
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.