Janet Craig's are noted for their dark green glossy leaves and their tolerance for low light. Like many other members of the dracena family they like slightly dry soil. With dry soil their leaves lose their gloss and become cupped. Soil kept too moist promotes brown and yellow spots on the inner new growth. After a few years, these plants will acquire what we call age spots. Fluoride in the water is a main cause of this problem. Once these spots appear the condition is irreversible.
Cut stalk before the Janet Craig gets top heavy and loses its upright position. When the inner growth gets brown and yellow spots, gently split the leaf with your finger nail and tear the leaf in half to where it joins the main stalk, removing the entire leaf.