Why Does My Bougainvillea Lose Its Leaves?

bougainvillea image by Tina Stumpp from Fotolia.com

Bougainvilleas are tropical plants that grow on vines with clusters of pink, lavender, red, gold or orange bracts. A bract is a modified leaf. Bougainvilleas are frequently grown as an annual in areas with cold winters. The bright, elegant vines are easy to grow and often used to drape garden fences and add colour.

However, the leaves might fall off in certain conditions.


Aphids, small insects with soft bodies, move slowly, sucking fluids out of the plant. Their colour might be green, brown or black, and sometimes they have wings. Not only do they transmit deadly plant viruses as they suck the plant with their mouth parts, but they stunt the plant's growth, damaging the leaves and buds. The leaves in turn fall off, and the plant may die. To prevent aphids from attacking a bougainvillea, remove weeds.

Cold Weather

Being a tropical plant, bougainvilleas are sensitive to cold weather. Temperatures above 15.6 degrees C are ideal for this plant. It is frost sensitive. In the winter time, bougainvilleas grow dormant and lose their leaves.


Bougainvilleas require sunlight, either sun or direct sunlight throughout the day. Too little light will cause the leaves to fall off. If the plant's leaves are pale, or it starts to lose leaves, it might need more sunlight.


All plants need water. The amount of water needed for a plant varies from species to species. The recommended water range for a bougainvillea is dry to normal. Both over-watered and under-watered plants will have wilted leaves. According to www.backyardgardener, "Plants are almost completely made up of water so it is important to supply them with adequate water to maintain good plant health." Without enough water, roots wither and the plant dies. With too much water, the roots will lack oxygen and could become diseased (root and stem rots).

Perfect Conditions

With the right conditions, bougainvilleas can add a lot of colour to a garden. They require little maintenance and can tolerate heat and humidity. These flowers bloom from early summer to late fall, cascading colour for several months.