If you can't see the critter responsible, you can't know what to do about it. Try to catch 'em in the act. From what I see in this pic, I would look for caterpillars of some type. They drop a lot of little black poo, which may help give-away the location. If all of the damage is old (with brown around the edge of the holes,) the culprit may be finished/gone.

Plants outside get chewed on, usually not cause for alarm. Looks like the ground could use some mulch.

one way to find them... is to realize ... it puts out new growth from the center top ...

and there is no damage there ... so the bug is long gone ...

you need to watch this plant... thru the growing season... to see when new damage is being done .... and then try to find the bug ...

if you are in the phillipines.. that would have been good info to provide to us ...

to my eye.. there are only 3 bad leaves... i might just cut them off.. so they would quit bugging me ... pun intended

ken

To: purpleinopp, ken_adrian
Thank you for your replies. Will monitor for the culprits. :)

To: purpleinopp
Will cocopeat be a good mulching medium?

I'm not familiar with that, it sounds expensive. Almost any kind of dead material can be used as mulch, I use many different things, added to beds when they are available. Does the info here help?

Kitchen scraps are also great for composting in a pile or directly in the garden.

Without a compost bin or pile, you can slightly bury stuff that is or might turn icky. Dig a little hole next to the roses for example, drop your load, cover it up. Done, no need to move that later, like 'finished' compost. Anything that can go in a final spot the first time, that's what I do with it.

Buried or used as mulch, both forms of sheet composting. I was already arriving at this more lazy conclusion, then a back injury, then the ants convinced me I wouldn't get anything from a pile here anyway. It's all going to go on beds, might as well go there the first time I move it. It will decompose as mulch or in a pile, and seems like the closest thing to a natural plan as I can get, though even if I could still fork up heavy loads of compost and cart it around the yard, I don't think I would. Nobody moves compost around in meadows or forests, it just doesn't make sense to me vs. what I've been doing the past couple years.