Avocado Container Size

[kfog]

One of the avocados I grafted last year had been doing pretty well until the last month or so. Recently some of the older leaves are looking a bit yellow and a few have brown tips. It is growing in a container (around 4 or 5 gallons) in a  fast draining medium (EB Stone cactus & succulent with some extra perlite) and fed with a standard avocado/citrus feed. I'm wondering if the container is too small and could be contributing to the problem.  I have another slightly smaller grafted avocado that is growing in a similar container with the same medium and that one seems absolutely fine. So I'm really not sure what's going on. Would appreciate any advice or suggestions.

[pagnr]

Avocados in Australia are most often propagated in taller narrow pots or bags. This improves drainage and air in pore space in the pot overall, and more so in the root zone.
These type of bags, 7 litre tall or even 9 litre, same diameter are common.
https://nurseryandgardensupplies.com.au/product/black-poly-bags-7-ltr-deep/
Tall pots of similar shape might be useful, compared to more squat pots.
If the exact same pot mix is used in a squat pot and a tall pot, the drainage and air pore space ( air filed porosity ) will be better in the tall pot.

[kfog]

How about the yellowing leaves? Does anyone have any thoughts on that? Could it be lack of nitrogen? Thanks in advance for any suggestions.

[Plantinyum]

How about the yellowing leaves? Does anyone have any thoughts on that? Could it be lack of nitrogen? Thanks in advance for any suggestions.

mine also has this, with more of the browning at the tips. Only on the oldest leaves , and those are begginning to fall off. The plant is growing strong with new growths all over atm.  Ive read that the brown on the tips of the  older leaves is usually due to accumulated salts in the plant tissue, from fertilizers.  My climate is verry different that yours and my plant is inground ,so i dont know if were both having the same thing happenning....

[Mark in Texas]

One of the avocados I grafted last year had been doing pretty well until the last month or so. Recently some of the older leaves are looking a bit yellow and a few have brown tips. It is growing in a container (around 4 or 5 gallons) in a  fast draining medium (EB Stone cactus & succulent with some extra perlite) and fed with a standard avocado/citrus feed. I'm wondering if the container is too small and could be contributing to the problem.  I have another slightly smaller grafted avocado that is growing in a similar container with the same medium and that one seems absolutely fine. So I'm really not sure what's going on. Would appreciate any advice or suggestions.

I don't seeing yellowing.  Hard to beat Osmocote Indoor-Outdoor Plus, 6 mo. slow release, 15-9-12 with micros. 

You must retrain with staking or cutting back one of those side branches straight up to form a new central leader.  I did the goalpost topping about 3' up on a Reed and it never recovered from being all wonky.  A good freeze and I'm now back to a beautiful tree that I maintain to 12' H X 8'.