Doctors bury their mistakes,
Bartenders drink their mistakes
and Landscapers cover theirs with pine straw
Eddie Rhoades

Here are some from a GardenWeb thread some time ago. Cannot say who all the authors are.

Gardening Quotes

The less help you have in a garden the more yours it is.

My rule of green thumb for mulch is to double my initial estimate of bags needed plus three. Then I'm only two bags short.

Heaven is not merely over our heads but under our feet.
- Thoreau

You don't have too many slugs; you merely have a deficiency of ducks.

The best fertilizer is the gardeners shadow.

There is always next year.

A perennial is a plant that would have come back year after year if it had survived.

I consider every plant hardy until I have killed it myself. - Sir Peter Smithers

If you are not killing plants, you are not really stretching yourself as a gardener. - J. C. Raulston

Birders have their "life lists" of birds seen - it almost seems I have my "life kill list" with an indirect goal of killing more different kinds of plants than anyone else - and I'm well on my way. - J. C. Raulston

Weeds have rights too.

That plant wasn't a mistake, it was an experiment." - Janet
One part soil,
two parts water,
and three parts prayer.

A book is like a garden carried in a pocket.

He who plants a seed
Beneath the sod...
And waits to see...
Believes in God.

Anybody who wants to rule the world should try to rule a garden first.

God made rainy days, so gardeners could get the housework done.

A hand that's dirty with honest labor is fit to shake with any neighbor.

Give a weed an inch and it will take a yard.

He (or she) who plants a garden believes in the future.

Bloom where you are planted.

Perennials
First year they sleep, second year they creep, third year they LEAP!!!

A priest stops to watch a gardener tending her garden and says, "What a beautiful job you and God are making of that garden." And the gardener replies, "Yes, but you should have seen the mess it was when God had it on his own!"

Your mind is a Garden, your thoughts are the seeds, and the Harvest can be either Flowers or Weeds.

Come into my garden, my flowers want to see you.

When the world wearies and ceases to satisfy...there is always the garden.

Plant your own garden and decorate your own soul, instead of waiting for someone to bring you flowers." -Veronica A. Shoffstall

An hour in the garden puts lifeÂs problems into prospective.

There is peace with a garden, a peace so deep and calm.
That when the heart is troubled, itÂs like a soothing balm.
ThereÂs life within a garden, a life that still goes on.
Filling the empty places, when older plants have gone.
ThereÂs glory in the garden, at every time of year,
Spring, summer, autumn, winter, it fills the heart with cheer.
So everyone tend your garden, its beauty to increase.
For in it you will find solace, and in it you will find peace.

~ Earth laughs in flowers ~
by Emerson

"Life is a garden...DIG IT!"

My green thumb came only as a result of the mistakes I made while learning to see things from the plant's point of view. ~H. Fred Ale

Great Gardeners are like Great Cooks - if it is a failure, throw it to the dogs before anyone knows about it.