You can collect nectar from big flowers in full bloom by following steps.

  1. Tap   and open the walk view.
  2. Go close to the big flower in full bloom and open the detail screen, then swipe down to the flower to collect the nectar.  Nectars can be collected from this big flower only once.
  3. Once the big flower has returned to leaf and is in full bloom again, you will be able to get nectar from the same big flower again.

How to video: