Fleece can be used to extend the vegetable season, and netting protects plants from ground fleas and the cabbage white butterfly. But what can be used to stretch nets and fleeces over the beds? The market offers various ready-made sets. But individual arcs, suitable for one’s own bed dimensions, are hard to find. So in this article, I’m going to introduce you to several ways to make these bows yourself.
Are tunnel arches necessary at all?
In fact, you can also put a winter fleece directly on the plants. If you don’t brace the fleece tightly, but only loosely fasten it to the edges of the beds, then it grows along with the plants. Usually the plants have enough power to lift the VIies. However, this does not always work. Lettuce gets it z.B. not good at all if pressed flat, especially in a humid climate. Then it will be quickly attacked by fungi. Also other plants can be injured, if a heavy rain pelts on the fleece. At the latest from a certain size the plants will resent it anyway, if they are weighted down by a fleece. So at some point you will definitely need tunnel bends. If you want to use nets to protect against fleas and co., you also have to use bows. Because if the net only rests on the plants, z.B. the cabbage white butterfly can lay its eggs directly through the meshes on the leaves.
I have compiled sources for fleece and nets for you here.
What materials are available?
I have so far had experience with PVC electric rod pipes, PE water pipes, steel rods and rolls, and hazel/willow rods. The materials I present you here in detail.
The arches should have these dimensions
For the use of tunnel arches I can only recommend you to standardize your bed widths. Only in this way you can use all sheets and fleeces/nets with uniform dimensions on each bed. The length of the arches should be about the width of the fleece/nets. This fits, since the arches are still sunk a bit into the ground on both sides. As a rule, you should be able to get by with a standard size for almost all plants. The only exceptions are plants like rose and palm kale. For this you need longer sheets and correspondingly wide fleece and nets.
My beds all have a width of 75cm. Tunnel arches, fleece and nets have with me to it the length or. Width of 150cm.
Tunnel arches made of empty electric tubes
I saw this solution for the first time in the videos of the garden vegetable kiosk. The two work a lot with it. The tubes are available flexible on roll as well as rigid and straight. You can’t use the material on the roll, it’s too flexible. The rigid pipes, on the other hand, can be bent well. It must only not be too cold, then they break easily. In winter it is better to heat them up with a hot air blower. Unfortunately, they can not be well shortened with a pipe cutter. They also break easily. It is better to use a fine hand saw or a crosscut saw for this purpose.
The tubes are usually available in 2 meter length. As a diameter 16mm is enough. The length is sufficient for most applications. For Brussels sprouts z.B. the tubes should be a little longer than 2 meters. In some hardware stores, the tubes are also available in 3 meters length. Shipping is not profitable, because then you already have to pay for shipping costs. You can also put two tubes into each other. Each pipe has a fitting at the end, with which the pipes can be connected. For better durability, you can reinforce the joint with PVC glue.
To prevent long tubes from tipping over at the bed, you can stick thin metal rods into the soil and put the tubes over them. Well suited for this z.B. Construction steel bars.
The material is very cheap. If you look for z.B. on ebay for "Elektro Leerrohr M16" you can often find offers from 0,30€ per meter incl. Shipping.
Advantages: Very reasonable price, length can be adjusted by interlocking, can also stably span two rows of beds.
Disadvantages: Break resp. bend easily, plastic look.
Tunnel bends made of steel
Steel bends are usually included in the ready sets. However, they usually do not have the right length. In addition, ready-made sets are much too small (z.B. Fleece tunnel with 3 meters length and 40cm width). Strangely enough, you can hardly find individual arches to buy. And steel wire on reel is usually too thin or too flexible. In most cases it is rather tension wire for trellises and fences. For the tunnel arches, the steel should be at least 3, but better 4mm in diameter and quite stiff. I’m still looking for a suitable material on a roll, which might make it possible to get a better price for larger quantities. But so far without success.
The only usable material so far I have found at Gekaho. The dealer offers spring steel rods in 3mm and 4mm thickness and 170cm length. The rods also do not need to be shortened, because they can be easily stuck deep into the ground. At 75cm bed width 3mm is enough. Unfortunately, the rods are very expensive, even if you buy larger quantities.
Advantages: Durable material, requires little storage space, easy to set up, sleek look.
Disadvantages: Very expensive (from 1,70€ per rod)
Tunnel arches made of PE water pipes
I first saw the black PE pipes as tunnel bends at Ralf’s from the self-supply canal. In American Market Gardening videos you can also see the material, often the pipes are light blue then. The advantage over empty electric pipes is that PE water pipes are much more flexible, but still stiff enough to form stable tunnel bends. From a certain height (z.B. for Brussels sprouts) but the PE tubes need a stabilization by metal rods. Compared to the electric pipe rods, the PE pipes come as a roll. They therefore have a natural curvature and later retain the arc as a shape also. In my opinion, they can therefore be better stored or used. stow away. You can also simply cut them to.B. lean against a fence. I also like the look better, because the black arches on the bed do not stand out so as a contrast. Unfortunately, they are significantly more expensive than the white electric tubes. For this, they can be easily cut with a pipe cutter without breaking the material.
If you search for the pipes, you will often find them on ebay under "PE water pipe. As diameter 20mm is enough. The rolls are available in 25, 50 and 100 meter lengths.
Advantages: Stable, maintains shape, easy to cut, do not kink or break, can span several rows of beds.
DisadvantagesRelatively expensive (from approx. 0,80€ per meter
Tunnel bends made of willow or hazel rods
By far the most beautiful option are tunnels made of willow or hazel rods. If you have a stream with pollarded willows or lush hazel bushes, this also represents a possibility. I have experimented with this as well, because it could give me enough material for many bows for free. The handling is of course cumbersome, because side shoots have to be cut, willow sprouts again when it is fresh, and the material mostly lasts only one season. But the main reason I don’t use the rods anymore is that the surface of the rods is sometimes quite rough and also has small growths and the stubs of side shoots. All these places make it almost impossible to pull a fleece up and down without damaging it. Sometimes the friction caused by wind is already enough and the fleece rubs through.
Conclusion
The choice of material depends on various factors, some of which are pragmatic (cost, height of the arches), others a subjective matter of taste (appearance, plastic – yes/no). I would definitely recommend you to experiment yourself and research for offers. As always, it is worthwhile to purchase larger quantities. If a supplier does not show such discounts in his store, try to contact him directly and ask about it. I have already had good experiences with this.