Hi I need some help with my avocado plant, I have had it over a year and grew it from a seed.
I haven't got a picture of it at it's prime but from there it started to go down hill, the leaves turned brown/ black, I removed it from the windowseal thinking it was sun burn, but it continued even out of direct sun and I read it might be due to salt accumulation so I changed its soil.

When I was changing the soil the roots looked healthy and white.

Yet the probelm persisted and now I have lost some of the stem and overnight the black/brown has continued down the stem

Is this a type of disease I can't help? unfortunately I haven't got photos of the leaves but they started to turn black/brown from the edges and worked their way up the leaf.

Thank you I'm advance.

and hello!

I am sorry for your sad plant. It was a nice one wasn't it? However, I don't think it is worth recovery now. all you can do now is have the soil damp, not soggy, put it back in the windowsill, and wait.

It would not sunburn one day if it was living in the same spot all along. I doubt it was salts.

There are lots of easy long living windowsill plants but Avocado is not one of them.

If you try again, as you did have a lovely plant
give it plenty of light, like that one had, and not too big a pot, certainly this size looked OK. Caution on water; am not sure what happened, but it is very natural and tempting to see a plant start to fail and reach for the watering can, often NOT the answer.

Hi!
I grow avocadoes. All of my trees were originally started from seed. I have a 50 year old tree that was started from seed by the little girl that lived in my home prior to us purchasing the land. When her brother mowed the lawn, she would run out there to protect her little tree from getting mowed over. Avocadoes are trees, so once the plant has started growing from seed it needs to be treated as a tree. They don't want to stay small. If you try to keep it as a windowsill houseplant for too long it will die. If you put it in a large pot it will grow for awhile, but eventually it will die. I guess if the pot is big enough, you could keep it for awhile but ultimately it would take a magic trick to keep it alive. Fruit producing Avocado Trees have massive root systems and can only really flourish in the ground.
The alternative is to get an Avocado Tree that is grafted. I don't personally have any, so I can't tell you much more about them.
It's fun to put toothpicks in the avocado and start a tree. But when leaves turn black and die it's not from sunburn in this situation. Avocados thrive in full sun. I live in Florida, so when I say full sun, I m saying full force Florida sun.
I'm sorry to not give you good news. I know how much it hurts to lose a plant, especially one you started from seed.
Maybe another gardener here has a different story from mine.
I feel so bad, I don't even want to hit the finished button, hoping I can think of something. , but that's all I can say.