Has the plant been through any changes? Fertilizers & nutrients, sun, transplanted, etc...

Also, I don't think it is related, but that cup needs drain holes if it doesn't have any and it might be getting a bit small for the size of the plant.

At this point, it looks healthy. I wouldn't worry about it too much.

Thank you! I just transplanted it yesterday and I hope that it would start growing some healthy leaves soon. The only change I can think of is the temperature -- from 30C, it rose to 35 and above.

I would transplant them out of the seed starting medium they are too large for that type of mix. Can you pot them up to another mix or plant them in ground?

Is there any soil and or composted manure in the growing mix?

Have any herbicides been used any where in the vicinity?

If you are growing in containers, you should NOT be using SOIL as in top soil or garden soil or "dirt".

esox07, (fan of pike fishing?)

By that last comment, do you mean one should not be using ONLY soil in containers?

What would you then recommend for container growth medium? I've seen a bunch of your posts and pictures with large, pod-loaded plants, so you probably do something right! I'll be growing both sweets & hots in containers this coming season. I've had relative success with a not-so-precisely proportioned mix of fir bark, composted manure, soil, peat, perlite and vermiculite. The mix felt loose enough and seemed to drain well. I was however late in the season and had to resort to drastic measures to get a few pods.

Oliver,

I have a few small Jalapeno and mystery "Indian" peppers plants I overwintered that have similar curling of the leaves. I think this was a response to a re-potting and sudden increase of light & heat (moved them to an indoors mini-greenhouse). I'm pretty certain they'll bounce right back, as will yours.

isgen: Yes, that nick is a reference to Pike Fishing.

I use a close version of the 5-1-1 mix that has been discussed many time on this forum. It sounds like what you are using is close to that as well. But the mix should be heavy on the bark part.

I made up a bunch of the 5-1-1 mix a few years ago and am running out of it now. I don't know what I will do in the coming years. The only source I can find for bark is a very mixed size so I have to put it through two different sized sieves to sort out the pieces that are too big and too small. My back just can't handle that any more.

But it is good stuff for growing peppers. I see you in the same growing season as me. I think your problem with getting pods was a result of our short growing season and you should probably be starting seeds indoors prior to March first in order to have plants that are mature enough to put out in late may so that you time to get them to production by the end of the growing season up north. I start mine in mid February.

esox07,

My mix has nowhere near that ratio of fir bark, though I've put quite a bit in there. Perhaps I'll try to use more this year, hopefully I can find a cheaper source, ideally in bulk, instead of small bags meant for growing Orchids = $$$ if you want to fill out a few 5 gallon buckets. Last year's plants had been started early by someone else, but suffered from a wet and cool early summer and only started to do well when I potted them and brought them indoors under lights.

It is OK. The mix I have been using the last two years is more like 3-1-2. I have been re-using it and add more potting mix to it each season along with more perlite, lime and Osmocote slow release. Any bark you have will help.
The stuff I used, I had purchased from KMart, but like I said, I had to sort it.

Some people use the coco coir but I don't know much about it. But probably the more common substitute would be Perlite. It is fairly inexpensive if you buy it in bulk, which you would need because you are going to want to mix it pretty heavy since there will no bark. I don't know what ratio would be best, but probably something close to 1:1. At least 1:2 perlite to potting mix.

This does not look like a fertilizer problem at all. It looks like bugs. I highly recommend you check under the leaves. I had similar symptoms because of spider mites and these things are 1/32 of an inch in size. You often can't see them without a magnifying glass.

The rule of thumb is if the leaves are shaped normally but are drooping and curling, it's a water/fertilizer problem. If the symptom is asymmetrical leaves or malshaped leaves--it's bugs.