We are redoing our old deck and adding a new patio where our in ground pool used to be. I used the old railing that we pulled off the deck to make a trellis. I used cut down the ends so the sides where even and turned it lengthwise.
I bought 98 cent resin pots at Walmart and a little pit of chalkboard paint to label them. I then filled the pots with clippings from my larger herb garden. But you could always purchase herbs plants or plant them from seed in the pots.
Then I just used twine to hang them from the trellis. I wrapped the twine around the pot several times and tied it off tightly. Then tied the ends around the rungs of the trellis. The red pots and bright green herbs add a nice bit of color to our patio area. plus I plan on bringing the pots inside this winter for a winter herb garden.