Forget about verticillium. It is soil borne, not in potting mix unless, of course, you added contaminated soil.

Appears to be cultural/environmental. But we know too little about the environment and your growing practices to suggest much of anything.

My suggestion is to repot them into bigger containers with fresh potting soil. Your containers looks small, but I am not saying that is necessarily the cause, but it could have some bearing. But, if you repot to get some fresh, uncontaminated soil on them, you should probably upgrade your pots at the same time. I also suggest that you clean the roots off so you don't move any bad or contaminated soil over..

They need to hardened off to sunlight if planting them outside. If potting them up it will stress them. Though if they are flowering it sounds like they are already stressed. Oh and sometimes they have leaves die, and fall off. It just happens sometimes. Two of my best plants last year shed all their leaves twice and still went on to produce way more pods than I could have used.

Looking over your other posts, I would point to the cactus soil as being the problem. I commented with my experience on this thread http://forums.gardenweb.com/discussions/2138846/pepper-seedling-wilted-any-ideas

you can either run water in the sink to wash away the soil or bucket and dunk the soil and loosen it with your hands, I've done it many times with success, then repot the plants.

habjolokia has the right idea. Just rinse the roots in a bucket of water and the soil will eventually fall off. Then find some well draining potting mix. If you don't need a lot, Orchid Potting mix works great. It has a lot of pine bark in it which helps to keep it loose and airy. Plain old Peat Moss based mixes are not real good for peppers unless they have things like pine bark chunks or a lot of Perlite added to them.

Jes Lynn: Probably the commercial Orchid mix is almost all bark, but if you buy the small bags in the garden centers like Miracle grow, it is probably on 25% or so bark. If you can find true 100% bark chips, then just mix that with some regular potting mix.

I don't care for those "moisture control" mixes. I think that is a scam to sell plain peat moss for three times as much. Probably the easiest least expensive thing is to mix a lot of Perlite with regular peat based potting mix.

One of the better potting mixes is the 5-1-1 mix. If you do a search on this forum for "5-1-1" you will find a lot of info about it. It is just hard to find all the necessary ingredients.

Plain Miracle Grow potting mix will work. Avoid the moisture control. Most of the I have a problem threads involve its use. Some may use it with great success, they are the rare minority.

This is a helpful thread, I will check out the orchid mix for my peppers this year. I bought some Espoma mix I am also going to check out. Had anyone tried it on peppers?

I have not found the moisture control to be any different than regular peat mix. It is a marketing gimmick. The bag of nature's care I bought this year completely dried out and was almost impossible to get wet again.

Most peat based mixes are like that. Once they totally dry out, they become moisture adverse and it takes a lot of effort to get to accept moisture again. The key is to keep it from completely drying out without over watering.

if you are looking for a professional level results, go to a place that grows plants professionally(nursery/greenhouse near you) and ask what mix they use (not what they sell necessarily). This is how i found my favorite mix (from berger.ca), They stock it by the pallet in the back, since they plant most stuff in, it so i don't have to wait on shipping / processing and is nice to support local business. None of the places i went to used any of the bagged mix from big box stores like miracle grow.

Orchid mix is incredibly expensive so is fun to play around with at low quantities.

if you are looking for the newest hot mixes wood fiber / coco coir mixed with perlite is something you should look at.