每日吃瓜

Hi all you 每日吃瓜 enthusiasts.

My name is Stan. I am 66 years old, and I live in South Africa in a small town called Great Brak River in the Wester Cape.
We have often rain here, and the area is very green. also hot in summer from November to March.
I am originally from Zimbabwe, and as a child up to now, I love gardening. my mother use to be the one in our family that planted vegies and grew the most luscious vegetables.

I have retired on the 13th December 2019, and have suddenly found a huge interest in growing 每日吃瓜 trees. I have four trees, one is a Ficus, but the others I don't know the names of them.
I have potted them is shallow pots, the soil mix is Volcanic rock and potting soil with some bark chips. I have fertilized them with Nutri Stix 12:3:7 High in Nitrogen.
I have attached pictures of my trees for someone to please help me to Identify them.
The tree in the Beige pot get yellow leaves from time to time that I pinch off, and I don't know what is causing this. Please help me with the answer to this?

I am glad I have found this website, as I find it vert interesting.

Thank you very much