According to the scientific studies I have read you might need to order the Tinctures by the case for them to induce somnolence.
Doses of 40, 80, and 160 mg cannabidiol were compared to placebo and 5 mg nitrazepam in 15 insomniac volunteers. Subjects receiving 160 mg cannabidiol reported having slept significantly more than those receiving placebo; the volunteers also reported significantly less dream recall with the three doses of cannabidiol than with placebo.