Bulbs. The true flowers are tucked inside these leaf-like structures that come in bright colors. Make sure these nurtients are balanced in the fertiliser. Answer from NGA May 27, 1999. My Bougainvillea glabra had them big time in Santa Barbara every year come late July. Yellow leaves can indicate a deficiency of either of these materials, but too much of one will cause a deficiency of the other. Answered. ... am watering every other day, all of sudden dropping many blooms and some leaves turning yellow too much water, too little sun, what do I do, I hope to bring inside over winter and keep it (it's about 6 ft and was expensive) Answer from NGA Bougainvillea Looper. Root rot Plants that are over-watered or subjected to water logged conditions can develop root or stem rot. It might be now that we are in fall, the cooler temps have caused the leaves to turn brown and drop, as seen on many trees. About Bougainvillea Colors. Bougainvillea dropping flowers and yellow leaves Barbara Karst) - Knowledgebase Question. The bract color for bougainvillea may come in various shades of pink, red, purple, yellow… Bougainvillea Dropping Yellow Leaves - Knowledgebase Question. Fertilise your bougainvillea with a nutrient-blended fertiliser containing magnesium and iron. I recently purchased a bougainvillea whose leaves are turning yellow and dropping off the plant. Yellow or tan spots appear on older leaves may be sign of Magnesium deficiency (common with yellow bougainvillea varieties), or from over-watering. They’re inch worms & can be brown to green to yellow. the plants receive about 8 hours of sun, I have cut back on watering, i use coffee grounds 2X a week, bougainvillea food, removed, the juniper around it, added more mulch, more organic soil, but the leaves are all green, and have maybe 6 flowers between 7 bougainvilleas plants. These are the most common chewing pests which attack bougainvilleas that I know of. You can see how 1 of the leaves is rolled up. What is causing my bougainvillea leaves to turning yellow & fall off? Dahlonega, GA. Houseplants. Planted 3bmontgs ago, healthy soil, morning sunlight, weekly water....how do I solve this before it dies? 0. Bougainvillea flower drop can be caused by temperatures that are lower than those the plant is used to. Question by devildog5 May 27, 1999. First, note that the flowers you describe on bougainvillea are actually bracts, not petals. Generally, bougainvillea plants are hardy in U.S. Department of Agriculture plant hardiness zones 9 and above. What is the solution to this problem? There … My small potted Bougainvillea plant which has not bloomed for me all Summer here in the NYC area, is now starting to show signs of yellow leaves. Answer + 2.