I am very happy you have Ganesha as a blessing for your garden.
Ganesha is known as the remover of all obstacles and is called upon
before the start of many kinds of ventures. Sculptures of Ganesha are
usually found found at the beginning of a sequence of deities on the
exterior walls of a Hindu temple. He is placed there to remove
obstacles faced by the worshipper in his or her religious seeking.
Ganesha images are usually placed in niches on the south walls of
temples, where they are the first major images that devotees view as
they begin their clockwise circumambulation. This placement is
appropriate for a divinity who is regarded as the god of beginnings
and is to be invoked before undertaking any task. This role has
assured Ganesha's popularity with all Hindus. Even Jains and Buddhists
worship him. A Ganesha image sits atop my computer monitor right
beside my Buddha image. I'm Buddhist rather than Hindu.
Statues of Ganesha can be found in most Indian towns as well as
regions outside of India where Hinduism is common. His image is
placed where new houses are to be built. He is honored at the start
of a journey or business venture. And authors traditionally invoke
him at the beginning of a book or article.
How Ganesha came to have the head of an elephant is explained in
various stories. One account of his birth is that Parvati formed him
from the rubbings of her body so that he might stand guard at the door
while she bathed. When Siva approached, unaware this was his son, he
was enraged at being kept away from his wife and proceeded to lop off
the head of Ganesha. To ease Parvati's grief, Shiva promised to cut
off the head of the first living thing he saw and attach it to the
body. That creature was an elephant. Ganesha was thus restored to
life and rewarded for his courage by being made lord of new beginnings
and guardian of entrances.
In sculpture the position of Lord Ganesha's trunk has a strong
symbolic meaning. If the trunk turns to the Ganesha's left, that is
the direction for success in the world. If it is to his right, the
trunk represents renouncing the world. When one chooses a Ganesha
sculpture that is proper for their own spiritual path the trunk
position is one thing that is good to keep in mind.
As the god of beginnings, a logical placement in your garden would be
at, or near, the entrance and facing toward the visitor as he or she
entered the garden.
There are no hard and fast rules about such placement, so logic
combined with a knowledge of the god's attributes has to lead your
heart in the matter.
You will find more about Ganesha here:
http://ganapati.club.fr/anglais/adetformes.html - a detailed
description of the god and the symbolism surrounding him.
"The Hindu : Multiple forms of Ganesha"
And this article about the Ganapati Festival can fill in even more detail for you.
Search - Google
Terms - Ganesha - Ganesha image orientation - Ganesha image placement
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May you and Ganesha have many lovely years together.