Of course I'm concerned about ecology, I've been an organic gardener for 30 years. And as I said, I rely on client's contractors to build the beds and make them structurally sound. In my years in the business, I've learned which designs are problematic, and which designs are more durable, and I incorporate this knowledge in my design and material recommendations.

You can't tell much about the construction of the trellis from the photo I put up, so you don't know how I've modified it. In fact, I did put an extra hour of work into it, and as I said, I've had some in place, with minor repairs, for 4 or 5 years. With the shape they're in, they'll last at least another 5 years.

Trellises don't stay in the same place year after year, because you have to rotate crop families even in small gardens. So having a trellis bolted to the same place in a bed limits rotation and isn't ecologically sound. Sometimes, you don't want a trellis in the back, you want it in the front, to provide a cooler microclimate to shade cool-season vegetables. An in-bed trellis gives more flexibility than hardware-mounted external trellises. With your rolling planters, you can just change the crops you plant in that particular planter, but with a fixed bed, you have to rotate crops and their supports.

You're exaggerating on the durability of these materials, even the cheaper trellises I put in last years, not months. The drainage in my beds is perfect for vegetables, so they're not rotting out quickly. Even in 10-year-old beds, when I deep-dig and expose the bottom timbers, there's very little, if any, fungal etching, even along the seams of unlined beds.