Q.What Is Causing My Pittosporum Golf Ball To Have Brown Tips To The Leaves
I have cocopeat, Vermicompost and Garden soil. In what ratio should I use them for pots. Is there any other material which I can use?

Certified GKH Gardening Expert
I would recommend that, about, half of your mix needs to be cocopeat. This will help negate the effects of thick garden soil and thicker vermicompost. You can add the other two ingredient in equal parts to make of the other half.
So, one part vermicompost, one part garden soil, and two parts cocopeat will be ideal.
Test for good pH range, to be sure, and amend if necessary.
Be sure that you do not keep the soil too wet. It needs to dry out, thoroughly, down to about 2 or 3 inches between waterings. You may need a fungicide to combat an infection at this time.
Here are some articles that will help:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/soil-ph-plants.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
https://www.gardeningknowhow.com/ornamental/shrubs/pittosporum/growing-japanese-pittosporum.htm