Nematodes are microscopic and live in the soil. Damage done by nematodes would be to the roots. There are beneficial nematodes too that prey on "bad" nematodes and grubs. What it sounds like you have/had was some type of caterpillar. Sometimes they are hard to find but when you do just pick them off and dispose of.

I agree Jennifer. Should have mentioned it in my previous comment. Occasionally I see them during the day tucked in new leaves on our hydrangeas. Before I discover the rats I would do as you do and go out with a flashlight and a tall plastic jug with a small amount of the soapy water. Got hundreds from my small dahlia area. When I discovered the soya sauce and cooking oil method it did a better job than my picking. But then the rats came and would tip over my bait stations. Had to get rid of the stations and the rats. Now I use a form of white powder that is supposed to cut the earwigs causing them to die. Doesn't seem to work too well for me. I try to focus on the flowers and ignore some of the chewed leaves, but the flowers are also susceptible, especially as they begin to fade. No more bait stations, flashlights and soapy water for me. My dahlias are blooming well and their flowers look great, but I know the earwigs are there. Ugh! Anyone know what to do to attract earwigs only? Maxyck

Yellow/green plants sounds like something variegated. If so, too many possibilities to know which you've seen. Wax Begonias can take being out in the sun, but all day in Atlanta might be a bit much. IME with putting them in tons of sun, they will stay alive and bloom, and definitely develop a deep red color, but don't grow as quickly at all, not by a long shot. I'd recommend trying to find already-nice-size plants if you try this. Dragon wing would be another to consider. The leaves are green, but it makes a good amount of reddish (possibly more pink in some light) blooms. That kind would be a bit taller. Other red plants that might be enjoyable, small enough to go at the base of a mailbox... Alternanthera dentata, Swiss chard (green leaves with red stems & veins,) Coleus cultivars for sun. Dragons' blood Sedum might be a nice ground cover under the taller things, but would creep into grass without a border/barrier.

There is nothing for you to do. The plants are healthy and vigorous. The tears aren’t hurting them. If you are getting actual holes where parts of the leaf are missing look carefully in amongst the foliage and around the soil and pot. Any snails? Slugs? Insects? Caterpillars? If do pick them off and squash.