Earlier this year, investment guru Jim Rogers predicted that within the next decade farmers will be the ones driving Lamborghinis, while stock brokers will drive tractors or taxis. His contrarian proclamation has since fueled intense investor interest in the agriculture sector. But despite this growing interest, the majority of investors have yet to discover the sector’s most promising niche: sustainable agriculture.

Today, farming uses 80 to 90% of all the water consumed in this country, along with millions of gallons of chemical pesticides, hormones and antibiotics. After food is grown, processors and retailers ship it across vast distances before it reaches consumers. The result is a tangled web of farms, runoff, oil dependency and highly-processed or unripe food laced with chemicals. Sustainable agriculture offers a healthier, more environmentally-friendly alternative.

Two measurable factors are driving growth in the sustainable agriculture sector: rising oil prices and increasing consumer demand. Traditional agriculture is highly dependent upon petrochemicals. In fact, in 2006, when fuel and fertilizer prices began to rise, USDA researchers noted that most farmers immediately began to reduce fertilizer, fuel, pesticide and herbicide usage to reduce costs. With input costs on the rise, “sustainable” practices may become synonymous with “cost-effective.”

At the same time, savvy consumers are demanding foods free of pesticides, hormones and antibiotics. In an effort to appease these consumers, food companies like General Mills Inc. and Sysco Corp. have already been asking farmers to change the way they farm, from conserving water to limiting pesticide usage. Recently companies like Wal-Mart Stores Inc., The Kellogg Company and PepsiCo’s Frito-Lay have mandated conservation practices, and the few producers able to meet their requirements have been inundated with orders.

All this means that a new crop of agriculture businesses, ones with cost-effective, eco-friendly innovations, will experience increased demand for their products. A few investment firms have already begun to take advantage of this trend, seeking out these companies and investing in them directly.

My firm, New York-based NewSeed Advisors, invests exclusively in businesses that make a significant contribution to sustainable agriculture. By doing so, NewSeed hopes to provide investors with double-digit returns and a clear conscience. Our goal is to find small companies, even companies just starting out, to make seed-stage investments and to guide them toward profitability. It’s not a “beat them or join them” proposition. Agriculture is a $100 billion industry; there is room for everybody.

NewSeed is not alone in this thinking. Canadian investment firm Investeco has invested in sustainable agriculture companies such as Organic Meadow and Horizon Distributors. Black River Asset Management, a subsidiary of Cargill, also invests in sustainable agriculture companies as part of its broader mandate.