I agree, Cynthia! Here are a few that I like.

"Live as if you are going to die tomorrow. Garden as if you are going to live forever." -- J. Kipling

"Perennials can be moved! Many of them have traveled long distances in our garden. Had they belonged to a frequent-flyer club, I am sure a few would have earned a trip to Hawaii by now."
-- Fred McGourty (The Perennial Gardener)

"You can have either a great garden or a clean house." -- (I can't remember who said this, but I think
it is the motto of all great gardeners).

"Aside from the Garden of Eden, man's great temptation took place when he first recieved his seed catalog." -- Longfellow

Ha. Love these!

to NGA, Cynthia!
"By looking at our world through its gardens, we reaffirm the simple human capacity to create beauty on this earth." -- Audrey Hepburn

"For love of gardening is a seed that once sown never dies, but always grows and grows to an enduring and ever-increasing source of happiness." -- Gertrude Jekyll

"Anyone with an addiction, benign or malign, wants to share it with others." -- Christopher Lloyd