I've recently transplanted my rockwool cubes in soil and some of the plant leaves are turning yellow where some others are dropping down... Any ideas? I have a moisture meter and it says moist for all but not wet.
It's completely normal for the first set of leaves called cotyledons to yellow and fall off. Those are where the first dose of nutrients are stored to support itself ass a seedling. As for the drooping, probably over watered or your soil retains to much water. I would wait a few days before doing anything. I would need to know more about your grow though. What kind of lights, soil, size of pot etc.
I was hoping it was just part of the natural process, I'll wait a few more days then and let the soil dry before I worry. My grow right now consists of 8x seedlings in red solo cups (started in rockwool) with a mixture of 2-1 Pro Mix All Purpose and Perlite. They're under 4x 42w (150w) CFL daylight bulbs in a flat white box with an intake and exhaust fan. I plan to plant them outside in 5 gallon buckets when they're strong enough, kind of a budget grow.
Don't worry about the yellowing mine have done the same. Try not to give them too much attention jus let them be. Something g u might want to look out for is ph for water if u don't keep ur ph constant ur gonna run into problems that look like a toxicity or a deficiency. I ran into all sorts of problems cause my ph was not constant. Here some pics to show what happened to my other two Sent from my SM-G530T using Grasscity Forum mobile app
Both r same age. Lil one caught boron disease due to inconsistent ph levels caused major stunted grow and looked like was about to die Sent from my SM-G530T using Grasscity Forum mobile app