My bougainvillea plant hardly flowers and only at the tips. It has one very long vertically growing stem(if I may call it so).

enter image description here

Is this an example of apical dominance. If so how is it to be corrected? Do I have to cut the long step?

  • 1
    $\begingroup$ what is the water regime? what is the climate (day length and heat)? how much sun does it get? $\endgroup$
    – Hachiloni
    Aug 16, 2020 at 12:39
  • $\begingroup$ @Hachiloni Everyday a lot of water is added to it. It receives continuous fresh air, but direct sunshine for nearly 3 hours in the morning. In August, days are long with rain as it is monsoon here in India. $\endgroup$ Aug 16, 2020 at 15:15
  • 1
    $\begingroup$ This question and others like it are much better suited to Gardening & Landscaping. $\endgroup$
    – MattDMo
    Aug 17, 2020 at 1:26
  • $\begingroup$ Welcome to Biology.SE! Please take the tour and then go through the help pages starting with How to Ask questions effectively on this site. In particular, I'm voting to close this question because it would be a better fit for Gardening & Landscaping, but please don't repost (instead request migration). Thanks! 😊 $\endgroup$
    – tyersome
    Aug 17, 2020 at 20:58

1 Answer 1


bougainvillea is a qualitative short day plant meaning that it needs long, uninterrupted nights to flower. Most flowring accours when it gets 8hrs of light (=16 hrs of night).

India is a huge country so you need to be more specific or tell us how many hours of light the plant gets. Note that if it's exposed to light from the house/street it may not flower as the light intensity for photoperiod is much smaller than that of photosynthesys.

Flowering requires a lot of energy, even if all conditions are met not enough sunlight might prevent flowering. bougainvillea loves sun, give it as much direct light as possible.

According to fao, Paclobutrazol shortens the time to flowering in long day conditions, meaning that GA might delay flowering. Another way to prevent GA synthesis is to stop watering the plant. Once the leaf start to fall give it water again.

Don't water too much:

these plants need full sun & well-drained soils. After establishing, minimal watering is needed. Two or more irrigations with 3/4 – 1″ of water per week would provide too much water for the bougainvillea to bloom well.

What to do:

  1. Give it more sun
  2. Give it less water
  3. Induce water stress to prevent GA synthesis
  4. shorten the day, you may cover the plant with a dark cloth from the late afternoon to the morning
  • 1
    $\begingroup$ Yes, too frequent watering is what I have seen stopping flowering. I have seen them flower even growing with only indirect light. The gardening and landscaping SE is also a good place to ask. If your plant has been grown from seed, that may account for slower flowering also. $\endgroup$ Aug 16, 2020 at 23:11

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .