Originally Posted by Muarco
The soil is some generic gardening soil, I know was not wise and I'm considering transplant into a pot with better soil but I don't know if it's the right timing. There are drainage holes under the pot.
I think it is mildew.
- There is some blackish/blue residue or mold on the medium
- The dried up leaf in the back looks like it would have a lot of mildew spores on it under a microscope
- The white rings on the front leaf.
What I would do is chuck the whole thing out, clean the containers with bleach, and start anew with coco coir from Canna, Plagron or Biobizz.
- Put a perlite or hydroton drainage layer just high enough to cover the drainage holes
- From seed to mid-flower, feed with BioSevia (or Canna) flowering food at 0.4 EC, plus epsom salt at 0.1 EC and some trace elements. When the plant is in heavy flowering, feed with grow food (0.6 EC) and epsom salt; at this time, high nitrogen helps the flowers to grow and the potassium helps with forming bud's branches; at this stage also extra non-mobile nutrients Ca, S, Si and trace elements are required for extra cell growth.
- Growing organically, don't pH the tapwater, especially if it's naturally high in pH already.
- bottom water with clean tapwater only; let the tapwater stand next to the plants for at least an hour, a day is better, so the water and plants the same temperature and to let some of the chlorine evaporate.
- only feed again when the plant shows a sign of nutrient deficiency, if the bottom leaves and grow tips are in good shape and growing, don't feed.
This will prevent any under/over feeding and under/over watering.
Plants with cannabis' root system need a constant supply of moisture in the soil, and bottom watering or a water reservoir in the pot is the best way to supply that. And cannabis needs a lot of water throughout flowering too. It is only when the calyx hairs turn brown that the plant starts to attract more moisture from the air than it can evaporate, and at that time it requires a completely dry medium.
There is still plenty of daylight left for a grow this year. I've planted autos outdoors as late as late July.