Fertilizer or Plants food question

[Kakricas]

Greeting from Chalong!

 

I have planted these flowers (or how there are called) nearly 8 months already but they do not grow as they should (1cm every month). Does anyone of you know what kind of plant food or fertilizer i have to spray on them and how often?

 

Thank you

 

Edited January 25, 2021 by Kakricas
wrong photo attached

[LivinginKata]

We have these sort of bushes along the back wall in our home. My wife buys fertiliser pellets from HomePro. She can't remember the brand name. But just take a photo into any plant seller or HomePro garden area and they will give you sound advice.