Can you donate blood if you smoke weed?

Sydney • I'm Sydd and I am your leader.
idk if this belongs here or not but I'ma post it anyway cause I really need an answerrr... I have an appointment tomorrow but yea I have been researching it and it seems like weed and alcohol are fine but I am wondering if anyone here has had any experience with this... please let me know. wondering if they will detect it or not.