April is caladium planting time in New Orleans. Caladium corms may be planted when night temperatures are above 60 F. Caladiums prefer loose, well-drained soil and thrive in shade with dappled light. If you choose to grow caladiums in a sunny location, you will need additional water and nitrogen fertilizer. Also, the strap-leaf varieties tend to have better sun tolerance. All caladiums will benefit from a side dressing of nitrogen in the summer.
Blood meal is a good product to use at that time.