Mothers?

Okay so i have 3 strains ak white widow and MM i wana keep a mother for each but i dont no which are male or female what should i do i want to switch to 12/12 soon and was told that you cant clone on that cycle or stop the flowering cycle by switching back to 18/7 once you can identify sex....pls help?

you can take clones and label them. flower your bigger plants. when they show sex get rid of the males and the associated clones.
you can take clones from a flowering plant, it just takes longer to root.

ya thats true thanks for the advice