Hey Paul, love your videos. I’m an engineer. From an engineering standpoint, the rebar down the middle of the post doesn’t help add much strength to the concrete. The center of the post feels zero of the tensile load in bending. The rebar is there to add tensile strength to the concrete. That’s why they put rebar around the edges. As close to the outward edges but still in far enough to prevent exposure to rusting. I would do 3 rebars around the inside perimeter about 1/2 inch from the edges to keep the post from cracking during a storm. This way, the rebar will be able to take the tensile load and the concrete will take the compressive load. Concrete is only strong in compression. Technically the pipe itself adds to the tensile strength around the perimeter also, so maybe you don’t even need rebar. Time will tell. Try a few the way I suggested and see which ones work better few years later! Hope this helps!
Thanks. Made a few without the rebar to try out. My thought is that if the concrete cracks, the rebar and the triple walled drain pipe would keep everything together even with a bit of flex. 3 pieces of rebar would add to the cost, but be very sturdy. I’ve seen a farm that used 1/2 rebar and one 2x2 cedar post. They held up some mature plants.
"Try a few the way I suggested and see which ones work better few years later! Hope this helps!" Yeah, he's probably not going to be experimenting. A few years down the road, all the concrete have set and the dragon fruit have grown and matured. Going to be a bitch to change your mind at that point. You're just stuck with whatever you choose.
Hey bud, that rebar will rust over time and weaken the post from the center. If you must use the pvc I wouldn’t use rebar the pipe should give good support. I would cap the top and fill it upside down. Then dig the 2’ hole and compact it in around the post. For beginners using fast set will give them problems. Having all the concrete around the bottom of the post will block the roots coming through the bottom of the pot. The roots will want to follow the water out the bottom. Come check us out this summer I will show you how and why we setup our trellises. Love your channel lots of good info keep them coming. Mateo
I've visited quite a few old farms in our area. Rebar does rust in humid and wet places but in our climate, rebar is a great way to support these plants. Elk Creek used 2X2 pine wood and 1/2 rebar with wire to support many of their plants. Leo Manuel used 1/2 rebar to support his plants. Some of those plants are 20 years old and still being supported. Maybe you are right... time will tell.
Yes and they started to become weak and flimsy as the plants got large. The plastic became brittle too. I use concrete and rebar stuffed poles instead now.
This is a big waste of material, specifically the plastic and burlap are unneccessary. Since you are using concrete, the plastic pipe is really just to create a concrete form. However, now you are having to wrap with burlap which will rot away anyhow. You just use two form boards (cast on plastic sheet) and pour a proper concrete post. The DF clings to concrete just fine and the wood form can be used over and over. No waste, no plastic, no burlap. The wire tops simply won't work in a coastal location, they will rust out very quickly. Design a concrete form and make concrete tops with holes. I used a disc form but have seen rectangular. The form for post should have a ~3 inch square "peg" at the top and a matching square hole in the top piece so the top just slips on, no fasteners needed, nothing to rot or rust out. The post is lifetime, only rebar and concrete, two materials needed. If gophers aren't a problem, no need to put concrete around post, just tamp it in with water and no need for pot. This design uses so many unnecessary materials, most of which won't last the life of the DF plant. Plastic will probably be cracked up in 10 years from UV deterioration.
Everything is doing well so far and it's nice to not worry about plants falling in our 40 mph Santa Ana Winds. Forms are nice and another great option, especially when there is another person to help make them. It's hard doing it alone. You are wrong, in time, the epiphytic roots weave into the burlap and down into the pots. Also, the drain pipes fare well in the sun. You are right, a concrete top would be nice, but the rebar is the main support and holds up for at least 15 years.
Hey Paul, love your videos. I’m an engineer. From an engineering standpoint, the rebar down the middle of the post doesn’t help add much strength to the concrete. The center of the post feels zero of the tensile load in bending. The rebar is there to add tensile strength to the concrete. That’s why they put rebar around the edges. As close to the outward edges but still in far enough to prevent exposure to rusting. I would do 3 rebars around the inside perimeter about 1/2 inch from the edges to keep the post from cracking during a storm. This way, the rebar will be able to take the tensile load and the concrete will take the compressive load. Concrete is only strong in compression. Technically the pipe itself adds to the tensile strength around the perimeter also, so maybe you don’t even need rebar. Time will tell. Try a few the way I suggested and see which ones work better few years later! Hope this helps!
Thanks. Made a few without the rebar to try out. My thought is that if the concrete cracks, the rebar and the triple walled drain pipe would keep everything together even with a bit of flex. 3 pieces of rebar would add to the cost, but be very sturdy. I’ve seen a farm that used 1/2 rebar and one 2x2 cedar post. They held up some mature plants.
"Try a few the way I suggested and see which ones work better few years later! Hope this helps!"
Yeah, he's probably not going to be experimenting. A few years down the road, all the concrete have set and the dragon fruit have grown and matured. Going to be a bitch to change your mind at that point. You're just stuck with whatever you choose.
Wind proof for sure. I’m sure the dragons appreciate being solid as well. Looking good bro !!!!! Love the videos
Thanks 👍
Hey bud, that rebar will rust over time and weaken the post from the center. If you must use the pvc I wouldn’t use rebar the pipe should give good support. I would cap the top and fill it upside down. Then dig the 2’ hole and compact it in around the post. For beginners using fast set will give them problems.
Having all the concrete around the bottom of the post will block the roots coming through the bottom of the pot. The roots will want to follow the water out the bottom. Come check us out this summer I will show you how and why we setup our trellises. Love your channel lots of good info keep them coming.
Mateo
I've visited quite a few old farms in our area. Rebar does rust in humid and wet places but in our climate, rebar is a great way to support these plants. Elk Creek used 2X2 pine wood and 1/2 rebar with wire to support many of their plants. Leo Manuel used 1/2 rebar to support his plants. Some of those plants are 20 years old and still being supported. Maybe you are right... time will tell.
Why did you get rid of the white pots Paul? For aesthetic reasons?
Yes and they started to become weak and flimsy as the plants got large. The plastic became brittle too. I use concrete and rebar stuffed poles instead now.
This is a big waste of material, specifically the plastic and burlap are unneccessary.
Since you are using concrete, the plastic pipe is really just to create a concrete form. However, now you are having to wrap with burlap which will rot away anyhow. You just use two form boards (cast on plastic sheet) and pour a proper concrete post. The DF clings to concrete just fine and the wood form can be used over and over. No waste, no plastic, no burlap.
The wire tops simply won't work in a coastal location, they will rust out very quickly. Design a concrete form and make concrete tops with holes. I used a disc form but have seen rectangular.
The form for post should have a ~3 inch square "peg" at the top and a matching square hole in the top piece so the top just slips on, no fasteners needed, nothing to rot or rust out. The post is lifetime, only rebar and concrete, two materials needed.
If gophers aren't a problem, no need to put concrete around post, just tamp it in with water and no need for pot.
This design uses so many unnecessary materials, most of which won't last the life of the DF plant. Plastic will probably be cracked up in 10 years from UV deterioration.
Everything is doing well so far and it's nice to not worry about plants falling in our 40 mph Santa Ana Winds. Forms are nice and another great option, especially when there is another person to help make them. It's hard doing it alone. You are wrong, in time, the epiphytic roots weave into the burlap and down into the pots. Also, the drain pipes fare well in the sun. You are right, a concrete top would be nice, but the rebar is the main support and holds up for at least 15 years.