Ficus Benjamina cuttings leaves turning brown

[Java Guy]

I'm starting to have some browning and leaf discolorations on my ficus cuttings. They are about 2 months old...started out 4 inches long with 2 sets of leaves. As you can see in the pictures I have had some great growth in that time. This last week I have noticed the problems on the leaves you can see in the pictures. It has happened to all of my cuttings. I have never had an issue with the ficus these cuttings came from.

Growing conditions are under grow lights, temps between 75 and 80 degrees. Humidity maintained around 60 %. The soil is the same I use for everything including the ficus these cuttings came from...Baccto Elite hp high porosity 35/65, screened 1/4 pine bark, screened 1/4 pumice, and a little greensand. I water when the soil is fairly dry but I make sure it's not completely dry. The soil in the pictures looks really wet but that's because I just watered them.

I treat the cuttings and the ficus they came from the exact same way. The only difference is the grow lights. The parent ficus has never been under lights while the cuttings have always been. Could that be the issue? It seems odd that they grew so well under the lights until this last week. I'm stumped...

First picture is the ficus the cuttings came from.

 

[Sheal]

Ficus Benjamina. You're treating them too well Java Guy!

This plant survives on starvation. If you want them to survive discard the lights and the lovely soil, don't feed them and water when you remember. Basically you need to forget the fact they exist. Until the last couple of years I had them in my home for thirty years and got used to their needs, or lack of them.

This most recent plant of mine which I grew from a cutting stood almost 6ft tall. It stood by a west facing window and next to a radiator.

They prefer a light or sunny area that is draught free and don't like to be moved around. They also prefer their roots pot bound and I didn't feed mine in all the years I had them, which means they prefer a poor soil. Mine were planted in a cheap, shop bought compost and watered every two to three months. They can be temperamental and drop their leaves if they are disturbed. The compost in the plant above was probably only changed once in it's lifetime.

I've just looked at your picture again and I'm not sure it's 'Benjamina', the leaves look longer and more pointed than usual?