Third Quarter or Last Quarter Moon
The third quarter, or last quarter, is the postmenopausal woman, sometimes pejoratively called the crone. As the goddess, she is the Greek Hecate and the Celtic Morrigan. The waning moon is a time for divination overcoming obstacles, and relinquishing bad habits or thoughts. Customarily, weeding the garden and ploughing are done during this part of the moon cycle.
Source
The Pagan Book of Days
Nigel Pennick
Witches Of The Craft® 