Malhar, over the years I found the key to successful graft here in SoCal is to start with a healthy rootstock. I am in the minority here, I prefer to graft from mid April, otherwise, it’s hard to get scions until August from tropicalacres. Benefit of early grafting is, the scion gets a full summer to grow. I don’t like to graft in August or later because there is a high probability of the scion to flower in winter and continue flowering throughout its life. Here are couple E-4 scions I grafted on ataulfo rootstock (scions from tropicalacres) on 4/20/22. I had the rootstock for 2 years and it was probably 2 years old when I bought it. I left the third major branch to graft Angie but couldn’t find Angie scions. I will probably cut the branch and keep the tree as E-4 only. As you can see I have the pot against a brick wall to keep it warm at night. I use buddy tape to wrap the scions and graft union then tighten the union with garden Velcro tape. I use the same Velcro to stake the branches after the scion takes (~4 weeks later).
E-4 scions grafted on 4/20/22
4/20/22
Growth of the scions in 2 months or less