I've always been a city boy — I can't even coax a weed to grow. But I discovered a national treasure, practically in my own back yard, which made me wish my thumbs were greener.

Donna Frantz's greatest skill is not really the organic farming that has dominated her life for the last 16 years. No, she is the poster child for living your dreams with energy and ­passion. At 81, she is not about to stop learning and doing new things. You read that right: 81.

Donna and her husband, Leon, started a seasonal farmers market that grew into a year-round florist and gift shop that they operated for 21 years. She really wanted a farm, though, and looked for 19 years before she found one.

So at age 65, when most folks are contemplating retirement, they moved to the farm — her "25 acres of gold."

I recently spent four hours there as Donna proudly showed me her farm. I even had a chance to ride on her tractor — a first for me. As long as she can physically work the farm and her mind stays sharp, she has no desire to retire.

"The soil around Waconia, Minn., is rich and black and perfect for my lifelong dream to grow and share these fabulous vegetables with people," says Donna, who has been an organic gardener all her life.

The produce is picked fresh daily, washed and brought into the lower level of the restored 1890s barn, which houses her business, At the Farm.

She also sells seeds, herbs, flowers and vegetable plants. Her five employees, her "elves," taste everything before they sell the crop to be sure it meets her standards.

But the most important commodity Donna dispenses is wisdom: farming advice, to be sure, but also motivation, dedication, common sense and how to live with passion.

Her mom and dad were farmers. Her mother told her never to be a farmer.

"Mother had an A-plus work ethic," Donna said. "Dad said never, never, never worry. He just flew by the seat of his pants and had a let-it-flow attitude."

To live her dream, she ignored her mother's advice. She works every day — seven days a week. She's never had a vacation. Her vacation is on the farm. She loves work and can't believe she created this.

Every morning, she gets on her tractor and travels around her farm and continually reminds herself that all this is beyond her wildest dreams. She reads self-help books, not for enjoyment, but to learn.

I asked an employee to share Donna's secret: "She's always in the moment. She always wants to know what is going on in our lives and the lives of customers — success of kids, sickness, vacations, everything."

We do something similar here at MackayMitchell Envelope with our Mackay 66 customer profile.

I asked Donna to prioritize what made her successful. Aside from her first answer, which is what every good farmer would tell you, the rest of her advice is universal.

1. Soil. The soil smells good after it rains.

2. Quality of products. It's important to not be too economical and don't let the cost of your seed get in the way of quality. You must have good seed to be successful.

3. Research, research, research. If it's a new seed, you test and test. You will never know how good it is until you grow it and try it.

4. Be good to your customers. Tell them when you don't know.

5. Above all, be honest.

6. Stand behind your product. If someone gets a bad melon, they can throw it away and get a new one.

Donna said, "I don't care how many zeros you have in sales — from $1 million to $100 million — business concepts won't change. It's better than money when people like what you do."

Mackay's Moral: It's never too late to plant the seeds of success.

Harvey Mackay is a Minneapolis businessman. Contact him at 612-378-6202 or e-mail harvey@mackay.com.