Who: Wendy Volhard, 72, a dog trainer and author, is a former reporter for the Wall Street Journal.

What: Volhard Dog Nutrition makes and sells Wendy Volhard Natural Diet Foundation 2, a natural dehydrated dog food.

Where: Culpeper, Va.

Started: 2010

AARP: What's your advice for someone 50-plus who wants to start a food business?

WV: 1. Find something you really believe in and follow your instincts and ethics.

2. You need a good business plan; discuss it with an accountant and a lawyer. In my case, it was an intellectual rights lawyer, since I am dealing in recipes. Find out the exact costs of making the product. Also work out the overhead and profit margin before you start.

3. Rarely can you do this alone. Look at your own strengths and weaknesses and know your limitations. Hire people you can trust, and employ them in the areas in which you're weak. Pay your employees well, so they have a vested interest in growth of the business.

AARP: What's the best piece of advice you ever received?

WV: Always be in charge of the finances.

AARP: What's one thing you know today that you wish you knew when you started out?

WV: I wish I had been better at working out production cycles. That has been the biggest challenge. Leaving enough time to make sure that you have enough bags of food on hand right where and when you need it. You can't have any down time, which would mean product being put on back order — something that, when feeding dogs, you cannot do.

AARP: What was your best day at work?

WV: Going over the first year's figures to see if our adventure was a viable proposition and finding it was.

AARP: The worst?

WV: When I realized that I underestimated the demand for the product. Our products take a month to make from beginning to end — and learning when to order the ingredients, so there is a constant supply, was a learning curve.

AARP: What is a pay range someone might expect?

WV: $50,000 to $100,000 annually to start, depending how quickly you grow.

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