Originally Posted by Bonvondon
Ok, so everything was going well a week ago.
Im growing in a light organic soil. Potted up from 1.5L pots to 6L Pots 5 days ago. This time I decided to add some organic amendments to the soil. Plants are 4 weeks old.
Most of the plants seem ok but some have looked unhappy and have started to show rust coloured patches on the leaves and discolouration on the leaf tips.
I gave them a light feed of fish mix at 2ml per litre and also some bio silicone at .5ml per litre and that's it.
Feeling like i did something wrong with the soil mix. I added around 2-3 handfuls of each amendment to 50 litres of soil.
Am under a 600w mh.
Any advice as to what I should do would be greatly appreciated?
Whatever is going on is expressed as calcium deficiency. Most likely because the plant uses a lot of calcium at this point and the roots were slightly burned.
The soil mix you've described isn't very hot, however the dolomite lime takes a while to mellow out, at least a week and a month is even better.
However when you pot up, you have to always make sure the roots don't get into contact with hot soil, and that's relative to the soil the plant is growing in. For instance the plant's soil has an EC of 1.6, and the new soil an EC of 2.0, the roots are going to burn.
So the solution is to fill a pot with a drainage layer, then hot soil, then an inch of light soil, and put the plant's rootball on top of that. And fill in the sides with more light soil. That way, the roots can't burn.
Or grow in coco coir, which has no nutrients at all, and with which you can pot up at will.