What’s happening ??

They all don't adhere to the exact same time frames unless they are clones. Even seeds of same strain can have a lot of variance in this regard. Ensure no light leaks. Provide 12 hours of uninterrupted darkness. Have faith the plants are in flower and just taking a bit longer than the other 2 to show something your eyes can discern. The biological processes are already doing it whether you see it or not. It'll take 8-10 weeks for vast majority and a few can be shorter or longer, too. Being slow a first doesn't always translate to a long flower phase, but probably correlates a bit, but i've also seen plenty finish fast that looked slow early on.

Hello. A few thoughts are simple for this. Different varieties, phenotypes of plants. Due to this, some other blooms later. Perhaps the plants are located in boxing in the most successful way. If you look, it can be somewhere in boxing will be colder or windy than in others. Perhaps light shines on plants in different ways. It is also necessary to check for nothing to shine at night, the light does not go into the tent, in boxing. I would not be very worried and looked after the climate so that nothing to miss. Probably plants calmly bloom a little later, because everything just begins) Good mood and do not hurt there and bloom 💪

Looking at your diarie, its probably cause its 4 diffrent strains one even got the Name "Different" .. i would give it some time when flower starts the phyllotaxis change from opposite to alternate which occurs mainly in older plants or cuts or when flower appears

Mouse talk bull... as always T_T My last experiment was with 2 week plant, that i make to get flower (my first experiment with 6/18 schedule) There is a bunch ignorant ppl, who like to talk without actual experience...

maybe different phneo type, maybe light leaks, maybe just taking some extra time. I see pistils so it is sexed and ready. Plants will not flower till they are mature. Much like kids can't have babies till their mature and hit puberty. Its why photoperiods will not bloom at 12/12 from seed. They have to grow up a bit. 

You may just not be in flower for long enough. Are you sure there is no error with your light timer?

Ist es die gleiche Sorte? Die sehen jetzt nicht schlecht aus, könnte höchstens ein anderer Phenotyp sein. Viele Strains haben „Untersorten“ wie die Gorilla Glue #4 die berühmte „Thin mint“. Da unterscheiden sich die Nachkommen dann genetisch sehr obwohl es Geschwister mit den selben Eltern sind. Die eine Pflanze kommt eher mehr als Sativa die nächste als Indica… Ich glaube, genau diesen Effekt siehst du hi

If u like do Photos i'd like to introduce you to my way growdiaries.com/grow-questions/87557-myth-busting-part-12-618-schedule-myth-busted (u can also read some questions in my profile) And make your own desicions - make sure u do 12/12 or less hours of light - some photos need more time then the other - N excess can slow down the flowering