I have about 5 avocado plants grown from seed stage in containers. 2 are close to 2.5 years old and 3 are about a year or 1.5 years old.
The 2 oldest ones are not doing so well but the youngest ones have grown fairly tall and so I was thinking they're healthy. However, one of them shows some sort of burning marks. Any idea what may be going on?
On the other one they look brown and so half the leaves dry off. But they don't look like in the picture below.