I don't say whether you are fertilizing or not, but I would try buying a good fertilizer made for veggies and apply at half strengh every two weeks for consistent nutrients to get into your peppers. If they are only 5'' tall I'd say your problem must be soil quality. Other problems could be not enough sun or temps not being warm enough yet. I'm by no means a professional gardener but as long as you don't over-fertilize, it can't hurt.

Good luck!

I did not fertilize anything in bed. This is my new bed this year. I put in half top soil and half manure.
I'll try put more bonemeal and see if it works.
thankyou

I think I have the same problem as you. I build a new raised bed and everything is growing great except peppers. I can see now peppers are going to problematic at best.

I have 4 Valencia bell peppers, 1 Anaheim and 1 Thai Dragon. My bell peppers are really light green with leaves curled and not looking very healthy. Now my Anaheim looks like it has either fert burn or maybe too much water because bottom leaves are turning yellow starting at the tip. Complete opposite from my bell peppers, very dark as well. Thai Dragon looks ok nice color no problems there.

After doing some research I found out that bell peppers are apparent not only hard for me to grow but there are many others that just cant grow bells. One of the tips I read was to give it a nice foliage spray with epsom salt (magnesium sulfate). Apparently they need it and it helps regain that dark green color and just helps overall. I guess bells have higher magnesium requirements than other peppers.
I'm going to try that and see if that helps.

Here is a link that might be useful: My garden

I think many of us are in the same boat with the peppers. Mine match all that you've said; they seem to be about 5 - 7 inches tall and already have very small "bloom pods" on them (they haven't bloomed yet, but the little globe-like pods are there).

Last year I had over 50 pounds of California Wonder bell peppers from this same garden between eight plants. This year the plants are towards the south of the bed instead of the north - so they were not planted in the same spot.

Here is a link that might be useful: BsnTech Gardening Blog

You said half top soil and half manure. It may be there isn't much drainage. Did you add anything else to help the bed drain? My (amateur) experience is that peppers don't like wet feet.