to the foruoms, @cillajones
. I used to grow a couple gorgeous potted crotons. Sadly they died in the horrid freeze inside our winter-unheated recreational cabin in Central TX last February. They are not cold hardy below 40º.
I lost 6 of them being stupid and planting them outside and not protecting them 6 years ago. Now I know to keep them in large pots anbd bring them inside my city house for winter. They thrived sitting in a sunny window for me. Direct sun hit them about 3 hours a day. The sunshine is what causes leaves to get orange and red. Without enough sun, they stay green and yellow pretty much.
Then in spring, I set them out on the front sidewalk where they got bright light most of the day and 3 hours direct sun (only in the mornings). Texas afternoon direct sun will cook a croton, in my experience.
Your plants look like they need more water. I never let mine get as dry as yours appear to be in the photos. I made sure they were damp at all times else they would lose leaves to "dry, thin, crispy leaf syndrome", I call it. I haven't replaced the 2 that died last February, but here's what 3 hours direct sunlight and bright light rest of the day got me in Temple:
I miss my crotons and will be replacing them this year. Have been devoting most of my 2021 garden time to replacing outdoor dead trees/shrubs that bit the dust in February.