Valerian root is a supplement sold at many regular grocers now, whole foods, and certainly online. I've been taking it for decades. (though I do have prescription sleep meds also).
Valerian Root is fast acting. It will have you feeling sleepy in 20 minutes, and it will keep you asleep for 2-3 hours. You may be groggy when you wake up for 15 minutes.
Make sure you get Valerian Root, not just valerian. And know that the capsules are a little stinky.
I also like melatonin, but it takes 60-90 minutes to act.