Fertilizing bougainvillea: a useful guide and some mistakes to avoid making

by Mark Bennett

May 08, 2024


Native to the tropical and subtropical areas of South America, the bougainvillea is especially prized for its spectacular, colorful flowers (which bloom throughout the summer season).

Bougainvillea come in18 different species - divided into climbers and non-climbers - and they prefer sunny locations. They also grow quickly, reaching considerable height in a relatively short time.

In this article, we describe how best to fertilize bougainvillea.


Fertilizing a bougainvillea properly


Fertilizing properly is essential in keeping your bougainvillea healthy and vigorous. Like all plants, bougainvillea require the 3 main macronutrients essential for growth: nitrogen, phosphorus and potassium. That said, other micronutrients are also required, to wit:

  • copper and manganese are essential for photosynthesis and the absorption of nutrients;
  • boron and zinc are used for the formation of flowers and the vitality of the pollen;
  • iron prevents chlorosis and guarantees successful flowering.

A good fertilizer should contain all these essential nutrients, but you should also keep an eye on your bougainvillea: yellowing of the leaves, for example, could indicate the need for iron.

Making a DIY fertilizer can prove to be the most effective method for fertilizing bougainvillea properly - keep reading:


DIY fertilizer specially for bougainvillea


Making the perfect fertilizer for your bougainvillea is very simple if you use the right ingredients:

  • compost must always be the base material of your fertilizer, as this will naturally enrich the soil with nutrients;
  • coffee grounds or animal manure is useful for providing nitrogen;
  • seaweed meal or wood ash are excellent providers of potassium ;
  • bone meal will provide phosphorus;
  • finally, eggshells are a useful calcium supplement for strengthening cell walls.

Modify the proportions used according to the characteristics of your soil and fertilize every 6 weeks during the growing season to encourage flowering.

Mistakes to avoid making when fertilizing bougainvillea


To fertilize your bougainvillea properly, avoid making these mistakes:

  • Watering: adding fertilizer to dry soil can easily burn the roots. To promote good absorption of nutrients, fertilize only after watering the plant;
  • The right time: bougainvillea must only be fertilized during their growth period (ie. in spring or autumn);
  • Too much: excessive fertilization of your bougainvillea could be harmful to the roots inhibiting their ability to absorb nutrients effectively;
  • Incorrect pH: bougainvillea prefer slightly acidic soil and even minor deviations from an optimal pH could prevent roots from functioning properly;
  • Incorrect fertilizers: choose organic fertilizers rather than chemical ones for a healthier and more sustainable soil; also, choose a fertilizer that has a balanced ratio of nitrogen, potassium and phosphorus (the ideal being a 10-10-10 NPK ratio);
  • Monitoring: the use of a fertilizer may not be sufficient to encourage healthy growth of your bougainvillea if you do not keep an eye on it and make adjustments to the fertilizer as required (see the yellowing of leaves example given above).

Following this short guide, your bougainvillea should be healthy and happy!