Did you start them in peat pellets? If you did, they probably need some food and need their roots freed from the netting around the peat pellets.

My peppers also have not grown much despite theri roots being free in a large pot. Maybe not hot enough this year peppers like a lot of heat not sure what weather has been where you are.

i'm curious to see what others say too as my bell peps (not ornimental) seem to be stunted too. at least i think after stating them from seed at end of march that they should be bigger than 3-4 inches tall!

good luck!

Last year I had a horrible year for peppers. They stayed stunted and then shrivelled up. Not one shirk from a garden challenge, I have 26 pepper plants planted. They all seem VERY happy!!!!