Phra Mae Thorani

Phra Mae Thorani is a Thai and Laotian Earth Mother goddess sometimes depicted beneath images of the Buddha. 

The water she wrings from her hair represents detachment, which drowns the demons sent to distract the Buddha from attaining enlightenment.

The Buddha is often depicted with one hand touching the Earth, as a sign that he is seeking the Mother's aid in attaining liberation. This Earth-touching gesture is called the Bhumisparsha Mudra, and signifies the moment when the Demon Mara (delusion) challenged the Buddha's right to gain enlightenment. Mara claimed that his own spiritual achievements surpassed those of the Buddha, and his countless demon soldiers attested to this. The Buddha, in turn, called on the Mother Earth to attest to his worthiness. The testimony of a deity as important as the Earth Goddess trumped that of Mara's army.

Reading about The Buddha's use of the Mother Earth reminded me of the importance of regularly sitting on the ground (weather permitting). It gives a firm foundation to one's meditative practice, and an 'earth', in the electrical sense, for superfluous or unbalanced energies in the body and mind.
While sitting on the ground you can respectfully ask the Mother Earth to remove your physical and spiritual problems. This is something Shri Mataji Nirmala Devi has recommended.