A spectacular sight in the tropics and hot coastal areas of the Americas is the ever-blooming bougainvillea, a shrubby vine covered with bright and gaudy blossoms. Named in honor of L.A. de Bougainville, a French navigator who lived from 1729 to 1811, bougainvillea are native to South America. First described and classified in 1789, bougainvillea had actually been discovered in Brazil twenty years earlier. Since their petals resemble paper, bougainvillea are popularly known as Paper Flowers.
Botanically, bougainvillea are classified as Bougainvillea glabra, Bougainvillea peruviana, or Bougainvillea x Buttiana (which is a hybrid of the previous two.) There are other species, but most commercial varieties are selections and hybrids of these three main species. New hybrids appear regularly.
The flowers we associate with bougainvillea are actually red, purple, pink, lavender, orange, white, and bi-color bracts. True bougainvillea flowers are small, white, and tubular, appearing inside these colorful papery bracts.
Normally, bougainvillea grow as thorny vines, but recent efforts have produced mostly thornless hybrids. Another trend is toward the development of shrubby plants with more compact habits for container growing.
Light & Bougainvillea
Sunlight is probably the most important factor in bougainvillea cultivation. Bougainvillea need full to sunlight — no less or they will not bloom.
A common misconception is that bougainvillea bloom only during the fall, winter, and spring. Bougainvillea can bloom all year if properly grown in good light.
Growth in the winter can be retarded if plants are kept too cool. A hot greenhouse seems to encourage the new growth which leads to repeat flowering.
During the blooming period, NEVER let potted plants wilt or stand in too much water. Bougainvillea need a happy medium. After planting in the ground, hold back on watering a little until the bougainvillea begins expand its roots then water as necessary.
A top dressing with Colorstar bougainvillea fertilizer will get the growth off to a good start. Incorporating a well balanced slow-release coated fertilizer into the soil at planting time will encourage growth and blooming for a long time. Too much nitrogen in the fertilizer will cause excessive leaf growth, leading to delayed or aborted blooming.
Iron is vital for good green color, but tends to be unavailable to bougainvillea plants during cold winter weather. Soluble, granular iron works well, and, unlike sprays, will not stain leaves and blooms.
Bougainvillea bloom on new growth. With proper pruning, sunlight, and water, plants will repeat a blooming cycle in about 4 weeks.
A rule of thumb is to prune, once the blooming is over, one-half of the growth that ends in the bloom. For example, if the growth where blooming occurs has grown out 6 inches (see diagram), prune off the old bloom cluster, plus 3 inches of the stem after blooming. Also, pinching the tips of your bougainvillea encourages new growth and flowers and maintains a compact, manageable plant.
For winter protection of in-ground plants, mound or bank soil 6 inches over the roots and lower stems of the plant. Leave this all winter and allow the outer stems to freeze. In the spring, once the chances of freezing have passed, cut the plants back to this soil mound and wash the mound away, leaving the lower stems exposed. With steady light, warm temperatures, and watering, they should begin budding in about 4 weeks.
Keep potted bougainvillea plants out of 32 degree and colder weather by moving them in for the duration of freezing temperatures. If the leaves burn from wind or frost, give your plant good warmth and light. It should begin growing back within 10 to 20 days, and should bloom in the expected 4 week time frame.
Pests & Bougainvillea
Aphids are probably the only bougainvillea pest we encounter in the Brazos Valley. If you have a problem with aphids or any other pest on your bougainvillea, bring the pest in to Heirloom Gardens for a positive identification, and we will recommend measures for pest control.