Because the garden is in the middle of a forest and is surrounded by tall trees, most of the sunlight doesn't occur overhead, but at an angle when the sun is lower. My problem with using trellises is that they block the sun. The only place I can use a trellis is at the back of my beds, and because most of the vegetables I'm planting (like tomatoes, beans, peas, cucumbers) need support and if supported will grow upwards: I can't used a trellis or sticks on the front bed of my garden or else they will block the sun from reaching other plants. Any ideas?
What we have used is a frame with wire mesh like chicken wire. The frame is place where it will stand up. Like using two fence posts then adding the mesh. Although ours were much taller and had space at the bottom to let light in. It looked similar to this picture:
Invasive plants are Earth's way of insisting we notice her medicines. Stephen Herrod Buhner
Everyone learns what works by learning what doesn't work. Stephen Herrod Buhner
Is this forest part of your land? If so is it in the realm of possibilities that you might be thinning trees in the future? What is the orientation of your garden in relation to the sun's travel?
Most of the plants you mention like to have more than 5 hours of full sun to produce well, which means you are gardening in a spot that might not be close to ideal and that will eventually create more problems.
As for your question, we use cattle panels (4 feet tall and 16 feet long) to trellis our beans and we also have one for a tomato trellis.
The panels we use for beans are attached to the ground on the ends and they arch over a 2 foot wide garden bed that gets shade loving herbs planted in it under the arch .
The tomatoes are planted in straw bales (we get ours from an organic farmer) with the panel running the 16 feet of bales, the tomatoes are tied to this so we can harvest easier.
The arched panels are held in place with sections of rebar driven into the ground, they are attached with 3 wraps of bailing wire in two places so they are firmly in place.
The tomato panel is held by three, evenly spaced T posts and again bailing wire holds the panel to the posts.
Another method that might work for you is the 3 or 4 pole tipi style support.