After switching the light schedule, our supposed "autoflowers" have finaly started to show signs of actually flowering. Week 9, what a trip.
This grow is full of surprises and new lessons for me: the potting mix i have used for this grow is apparently purely peat (black and white peat moss) with perlite mixed in. After digging into some more information about all kinds of soils i found out that i was apparently growing "hydroponically" because this is apparently a soilless mix. The world is full of surprises 😅
This does explain a lot of the stuff that i've been trying to deal with in the last few weeks: first and foremost my plants were looking like they were developing a range of different nutrient deficiencies. I still find it hard to tell which ones, but symptoms ranged from decoloration and deformation of the lower leafs up to small burnt tips on the developing flowers, new growth being brittle and signs that looked like underwatering. I'm convinced that this has a lot to do with the fact tht this is a soilless medium with 0 pre-supplied nutrients (the light mix does supply nutrients for a week or two, but no more). I've been going really slow on the feeding because in previous runs i tended to overfeed and had issues with that, so therefore only used about a quarter to half of the recommended dosages.
So, at this point i've completely switched up my feeding: i bought 2 new bottles of hydroponic fertilizers (GHE Bloom and GHE Micro) and i'm using those in addition to a little bit of plagron terra grow - to make sure the plant also gets its fair share of nitrogen. After 3 days of watering with this stuff (both at 2ml/L) the plants are almost literally screaming "THANK YOU!" and seem to be really benefitting from this new insight and change of strategies.