The royal Poinciana, or Delonix regia, comes with many names. Known as the flame tree, fire tree and flamboyant tree, the royal Poinciana produces large, fiery red or golden blooms that blossom from spring through summer. This fast-growing, deciduous tree develops fernlike foliage and takes on a natural umbrella shape. Its tolerance to poor soils and hard pruning make it an excellent selection for bonsai.
Choose a wide, shallow planting container to accommodate the wide-spreading root system of the royal Poinciana. Be sure to select a container with several drainage holes to promote a well-drained loam.
Incorporate equal amounts of coarse sand, nutrient-rich potting soil and organic compost, such as pine bark. Add a pinch of pure sphagnum moss to the mixture to increase the mixture's water retention. Add just a small amount of moss as it will grow throughout the soil in time.
Cover each of the potting container's drainage holes with mesh and fill the bottom third of the container with soil. Center the royal Poinciana in the container and fill the remaining two thirds of the container with your soil mixture.
Irrigate the newly potted Poinciana with tepid water to promote a good establishment. Water the bonsai evenly and thoroughly until the excess drains from the holes.
Irrigate this bonsai deeply and infrequently to provide a slightly dry environment. Check the loam's moisture levels daily and water your Poinciana bonsai when the soil begins to feel dry. Never allow this bonsai to dry out completely and avoid overwatering the Poinciana, to prevent root rot.
Feed your Poinciana bonsai in the early spring, just as the growing season begins. Use a well-balanced, slow-release fertilizer such as an 8-8-8 or 10-10-10 combination. Feed the bonsai again in midsummer. Avoid heavy fertilization as it will reduce the number of blooms in order to produce heavier foliage. Allow the young Poinciana bonsai as long as five years to produce its first blooms
Prune this vigorous grower to maintain its health and shape. Hard prune this bonsai in the early spring just before the growing season begins. Remove dead, damaged and wilted branches and stems. Trim back branches to promote the desired shape.
Prune the bonsai several times throughout the growing season. Thin the interior branches and stems to increase light penetration and air circulation throughout the tree. Prune back vigorous growing branches to maintain shape. Always use sharp, sterile pruning shears.
Repot the Poinciana bonsai annually. Root prune this bonsai during the process. Use sharp, sterile shears to trim back about a third of the root system. Remove dead and wilted roots before healthy ones. Trim deadened roots back to the root mass. Repot the Poinciana bonsai in fresh soil with a clean container.