There is some evidence that indicates insect pests are drawn more to plants under stress then to healthy plants, so while that plant might have looked heatlhy it may have had a nutrient problem.
What is the pH of the soil in that bed?
How much organic matter is in that soil?
How well does that soil drain?
How well does that soil retain moisture?
What kind of life is in that soil?
Insect pest control for organic gardeners is not a one spray, once a week, program since any of those types of materials are very broad spectrum and will harm the beneficial insects as well.
What is the problem?
Does this require some method of control?
What is the least toxic means of control I can use?
Did that control measure work?
Back to step 1.
Any pesticide must be used with due care but the least toxic usually start with mechanical (squishing, cutting) methods and then progress to maybe plain water to maybe Insecticidal Soap to short lived substances such as Neem Oil products to maybe the pyrethrin based poisons, all of which do have the potential of harming the beneficials if not used with due care.
Some of the botanicals that are no longer acceptable to organic growers would be Rotenone, Sabadilla, nicotene products and spinosad should be included since it is extremely toxic to the pollinators.

I just had shoulder surgery, so I can't answer all of you questions. Re read my post. They are all healthy and in the same bed with the same soil and fertilizer. I don't use any chemicals. That's why I posted on this site. I thought maybe the Cherokee was a weaker type of plant. Looking for someone that has grown them before.

I think it is pretty well agreed that cherries in general are considerably more adaptable and rugged than the OP heirlooms and even than the hybrids. The heirlooms have all kinds of susceptibilities, of which I am very far from expert. Cherokee may easily be a weaker cultivar than your other specimens.

I was thinking that or maybe it was just chance where the eggs were deposited? Maybe it tastes the sweetest to the bugs? None on the Sungold now that I think of it. They started on the base of a Roma or grape tomato.( It's an unknown that came up in re-used seed mix.) They didn't stay there long before they moved to the Cherokee purple. I had never grown heirlooms before, so I thought I would try them this year. I'd like to stay away from the hybrids. I do have some Mortgage Lifter seeds I could try. By the way. I only have had 2 Army worms. I googled it. The ones I thought were army worms are very tiny. They are a dark gray with a black stripe up their backs with blue heads. They don't get much bigger after dining on my plants. I never saw so many of one kind of worm on my plants. I guess I've been lucky? I am surrounded by woods, so it could be just about anything. I wish I was younger. I'd go to school for Entomology!

With all those worm types, and I am not an expert in this, but I think they probably come from some type of adult moths which layed their eggs on or near your plant.
I would try Bt which kills alot of moth types. Or, an insecticidal soap spray to keep the leaves clean might help. Also keep enough space around the plant for it to dry properly after the rain, the critters always seem to multiply faster in wet and overcrowded garden conditions in my garden I have found. I use BT sometimes if infestation occurs, it hasn'tseemed to harm my beneficial earthworm population. It has helped my grapevines alot. We have the grapevines near the woods and have had alot of insect problems coming from the woods.
Terry

Bacilluis thurigensis - Kurstaki, BtK, might be of some help if applied early enough in the life of the insect larva.

terry has the problem! Over crowding. I tried to jam so much in this bed. Everything seemed nicely spaced but went bonkers when it hit the compost/black cow. I did see a white moth in the area for a few days. Hornworms are an always kinda thing here. I will buy some BT. Thanks for the advice.

I spray my plants with BT from day1 every two weeks whether they need it or not BECAUSE of the fact that it isn't effective when the caterpillars are older. I know thisa goes against the rule of "identify problem, then treat," but it's not like there aren't going to be any hornworms or loopers after living here for 45 years -- they're here EVERY year. The other reason why I go against that rule with BT is that it is very "target" specific. It only effects caterpillars.

Btw, yes spinosad is harmful to bees, but it also is more effective at getting the older(larger) ones. This is why it's recommended to spray at dusk when bees aren't present.

Regarding why they're picked your Purple. I think they just prefer certain cultivars over others. Last year I had 3 pepper plants(all different varieties, same medium), in my driveway in containers and I must have missed a treatment of the BT because the next thing I knew my Naga was stripped overnight twice by a couple of hornworms. Didn't touch the other 2 plants. Who knows?

Good Luck.

Kevin