A brief tutorial / guide
BambooArchTrellis_Tutorial_v008
By Brett Leeper, 2025
See also blog post(s) about this here with more photos and some personal context and history.
Table of Contents
Image Gallery
Intent and Outcomes
Suggested Tools
Design Goals and Hypotheses
Disclaimers
Design, Layout, and Construction
Harvesting, Processing, and Cutting Canes
Twine and Knots
Watermelon Hammocks
Vining Garden Plants
Image Gallery
Intent and Outcomes
This document will provide a guide or tutorial for the reader to create an arch trellis tunnel out of just bamboo canes and natural fiber bailing twine, such that vining garden plants will climb the structure and that a gardener should be able to walk under the arch, train vines up as they grow, and harvest produce in the comfort of the shade.
Suggested Tools
- 18v battery operated handheld disc cutter / angle grinder
- Leather-only gloves while operating disc cutter
- Impact safety glasses while operating disc cutter and handling sharp bamboo.
- Latex dipped grip gloves for handling rough bamboo and removing branches.
- Natural fiber baling twine
- Knife or scissors or similar for cutting twine.
- Optionally, a step stool if you’ve made the structure too tall to comfortably tie twine overhead.
- Optionally, A second human especially during cane arch placement ought to make things much easier.
You can try to use a machete or similar primitive blade to cut bamboo instead of an ablative cutting disc, but the blade will dull or bend quickly on the hard material and require constant sharpening, so really, don’t.
Design Goals and Hypotheses
The design shall be producible and serviceable by hand with no more than hand tools or hand power tools.
The design shall use only bamboo canes and natural fiber twine, with no plastics or heavy-industrial materials. Bamboo readily reproduces with minimal processing. Several fiber sources could hypothetically be homegrown, retted, and processed locally. At bare minimum humans should be able to source string or cordage somewhere.
An arch trellis will allow a human gardener to transit under and through it, where they will be shaded in the late summer and have excellent visibility of all hanging fruits and pests.
An arch trellis will generate more growing surface area for vining plants than a simple flat ground plane, while reducing mildew and slug exposure on the ground. The growing plants should shade each other and their roots more and more as the heat worsens in the summer.
A diagonally criss-crossed arch structure ought to provide more stability and bear more weight than simple parallel arches with horizontal canes, and certainly outperform a simple teepee.
Simple twine hammocking can be added in place to support heavy fruits like watermelon.
Disclaimers
Strongly consider instead making a trellis with galvanized cattle pannel and t-posts.
This structure only lasts two or maybe three years outside in the elements before it really breaks down. This bamboo trellis is highly labor intensive to build. Power tools and blades for cutting bamboo can be expensive. Power tools, blades, and pointy canes can be dangerous. You could catch a tick transmitted illness working outside.
Design, Layout, and Construction
The design of this arch is composed of a tesselating pattern of parallel and intersecting bamboo arches tied together with jute, sisal, or hemp baling twine.
Each individual arch is composed of an overlapping pair of whole bamboo canes whose branches have been removed, lashed together for a distance of a few feet at the thin and most flexible distal end of each cane as each tapers to a minimal thickness. These are then trimmed to a similar length as their counterparts using the disc cutter at an angle diagonal to the cane to form a pointy stake for inserting into the ground. These arches flex back up and into place to resist downward pull both individually and moreso collectively.
The overhead plan shows two mirrored, coinciding rows of regularly repeating arches straddling both sides of a shared length of tunnel, each arch at a diagonal to the length of the tunnel.
Each arch in this row begins on one side of the tunnel and terminates on the other side of the tunnel. The ends of each arch must not terminate where another begins, and so either the arches of each row if evenly mirrored across the axis of the tunnel must terminate on a half integer offset down the length from where canes begin, or else the two rows whose arches’ ends terminate on the self-same integer down the length as their beginnings must be staggered down the length of the tunnel a half integer from the other row.
The whole integer between parallel, repeating arches might be for example 8 inches apart and the half integer 4 inches apart. The distance an individual arch in the mirrored scenario might step down the tunnel length might be 5 and a half integers. The tunnel width might be 10 feet across, and its length as long as you want, At bare minimum it is necessarily at least the arch step distance for one single structural arch cross up top, and at least double the step distance if you want at least one full diamond strutural cross spanning the top and bottom.
A second human operator to help steady, place, and bend canes for these next steps in the assembly process may be particularly helpful.
The canes are not so flexible as to enable weaving of the two concurrent structural rows, rather one row will be laid down and then the second row over it.
Massage the canes into place such that the diamond pattern evens out and then tie the canes together at their intersections with twine. Creating looser, simpler ties before committing to cane placement may be helpful.
The bottom far ends of the tunnel will need filling with shorter segments of bamboo to complete the pattern.
Harvesting, Processing, and Cutting Canes
The height and width of the tunnel, as well as the step distance of an arch, will be determined by the properties of the available canes. Individual canes must be of a certain range of flexibility, length, and thickness such that they can all reach overhead with sufficient overlap and bend without snapping. This varies by bamboo species and cultivar. Canes 1 to 1/2 inch in diameter, and 14 or so feet long were used by this author. fresh green canes are the most flexible, older golden canes freshly cut are usually serviceable, but old grey canes or drying canes cut too many days ago are prone to snap. This is especially frustrating when you’ve spent the time to trim to size and twined them already. Drying out the ends or burning them with a propane torch would help prevent greener canes from rooting if you have root buds you can’t trim off.
Upright canes growing from the ground are easily cut with a handheld 18v disc cutter / angle grinder. I strongly suggest wearing leather gloves with no fabric liner when operating the disc cutter to provide ablation protection without fabric getting pulled into the disc. Cut near the ground to not make sharp traps for later but do cut above the soil and above any visibly rooting nodes.
Wearing latex dipped gloves for grip and protection, snap branches off of the cane by grab the cane with one hand above the branch, and with the other hand pull downwards towards the cane’s base, the other hand bracing the cane above the branch.
Fragile extra thin segments will be removed from the upper distal end of canes, as determined by whether or not a given segment survives the snapping off of its lateral branches or otherwise rip apart easily. Further removal from the distal end makes them unsuitable at least for full arches, because the smooth transition of flexion resistance down the length is necessary when pairing cane ends into arch segments to prevent snapping when bent. For this same reason bridging a third piece is also incredibly fraught.
For arch pairs, Sort and pair canes together of like diameter and length to avoid snapping and mis-shapen arches.
Trimming and cuttin with the disc cutter are peformed on felled cane laying on the soil, with the cane secured for example by one shoed foot pressing it to the ground or by a partner.
Twine and Knots
Baling twine is probably the most economical, and is readily available in sisal natural fiber at farm stores in large spools, and they can be ordered online in jute. Please let me know if you can source hemp or other bast fiber twine at a good price.
Jute compared to sisal is itchier but softer on the skin of the fingers. Jute is thinner and more pliable and easier to tie knots in.
This writer got by entirely with four knots:
- Half knots, that first half of a default shoe lace before the bows
- Square (reef) knots, when you do do two half knots in a row and can’t get your shoe off.
- Lark’s head knot aka cow hitch, a common macrame mounting knot wherein a length of twine folded in half is extended loop end past a cane and the loose ends are threaded on the other side through that loop thus presenting two usable lines, to secure twine from the trellis for hanging supports.
- Overhand knot, basically a half knot tightened onto itself on a single cord.
Apply a half knot to tighten the twine looped around the cane first on the back side of a cane where you intend to then tie a square knot. To fix twine in place down the length of a cane, tie square knots on either end of a node, the bulging cross-section rings where hollow segments of the cane join.
The lashed together distal ends of canes in the middle of an arch may be joined with several individual knots, however they are better protected from later snapping by more continuous reinforcement through this delicate section. After anchoring twine with square knots to a node at one end of this length, lace the twine snugly back and forth down the length using a half knot at each intersection, securing with square knots a couple times here and there at nodes in between.
Twine lends a better climbing surface for vining plants than does the smooth bamboo surface, especially at the very vertical base of the arch where it needs the best grip. The reinforcing back and forth lace suggested for joining two canes at the middle of an arch might here be applied loosely to the rest of the cane or the lower portion, or one might loosely spiral twine up the cane tieing it at top and bottom.
Horizontal runs of twine bisecting the vertical diamonds formed by bamboo canes, and looping around each intersection to secure it, may provide extra climbing lattice in that most open part of the pattern, and extra support for hanging fruits.
Watermelon Hammocks
Heavy watermelon with their thin stems require extra support as they grow and mature or they will fall off the vine. A simple hammock or basket may be constructed in situ for each needful fruit. Here we describing something resembling a basketball net closed at the bottom, made with a simplified macrame. Using lark’s head knots, mount 4 or more cuts of twine from the trellis surrounding the anticipated size of the melon to present 8 usable hanging lengths. At a set height, tie each lark’s head pair together with a square knot and then divide these pairs to create square knots with their neighbors to tie them all together into one ring, and back together again, proceeding thusly downwards while drawing them in slightly closer with each iteration eventually closing the basket at the bottom with either an overhand knot with all the cords drawn together, or much more elegantly with a wrapping knot from macrame.
Vining Garden Plants
Vining vegetables benefit from frequent corrections to best climb the trellis vertically, especially early during the season. Guide plants to supports and redirect wayward curling tendrils early before they tighten and mature.
Indeterminate tomato varieties which keep growing to an unfixed size, as well as cucurbits which include muskmelons, watermelons, cucumbers, squash, pumpkins, etc, all can be encouraged to grow upwards to cover more of the trellis by snipping off lateral branchings which divert growth energy. These emerge from between the main stem and leaf stems. Take care not to snip flower stems which grow similarly. Let them branch more freely to infill the trellis when they have climbed closer to the top.
Cold-hardy perennials should regrow from the ground each year to be properly suited to this temporary structure, so speaking for my own latitude I’d suggest American Groundnut (Apios americana), a blooming, tuber-forming, and nitrogen-fixing fabacea, or the delicious Maypop Passionflower (Passiflora incarnata).