Soil and Water
The Bougainvillea plants thrive well in almost any soil, which is fertile and bears water drainage capacity. Therefore there is no such specification for soil variety for the plant to grow well. It must be remembered regarding growing Bougainvilleas that the plant should not ever get completely dry in between the watering. This does not mean that you should have water standing at the base of the plant. It is just about keeping the container moist. Never put a saucer below the pot bearing the plant. During the warm season the plant will drink lots of water and during cooler times that is in winter it is better to bring the plant indoors. It is the time when the plant won't require much water.
The water requirement of the plant depends on the following elements:
Type of Soil
Plant Size
Root System
Air Temperature
Light
If you are looking for the best result then it is wise to place the bougainvillea plant under full blaze of sun. If the plant gets at least 5 hours of full sunlight a day then it will lead to a good bloom. The more the plant will get direct sun the results will be better. The plant thrives in shades or partial shades as well but in that case there will be nice rate of growth but very limited bloom.
Temperature
The optimum temperature required by bougainvilleas is 70-85 F during warm days and 60-70 F for cooler nights. The young plants get damaged due to frost to a great extent. Although, a light frost is not so harmful as in that case the leaves might fall off but soon re grow after some time.
Fertilizer
Fertilizers bearing high phosphorus and other micronutrients and certain amount of magnesium are good for bougainvilleas. The fertilizers should have a slow or time released action. A small amount of nutrient should always be available to the plant, as this helps the plant to grow. If the soil is dry then do not apply the fertilizer. Never over fertilize.
Pests
The pests that often invade the bougainvillea plant include mites, caterpillars and aphids. Due to them spots appear on the foliage and the soil often stays wet. If situation like these occur then it is better to consult advices from the experts from the local nurseries.
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Baresh Raymond
I am a bougainvillea enthusiast... and have been gardening with bougainvillea for the better half of 15 years. As a result, I frequently write bougainvillea related articles. If you'd like to learn more about bougainvillea, you can visit my blog.