A small Lakewood, Colo.-based grocery store and vitamin supplements chain is betting big that the demand for organic products will continue to rise, and it is planning an initial public offering (IPO) to free up funds to compete with larger rivals.

Natural Grocers is seeking to raise $115 million in capital to help pay down debt as it continues to carve out a niche with small showrooms in markets ignored by larger rivals such as Whole Foods Market Inc. (Nasdaq: WFM), according to a report Monday from Supermarket News.

The company operates 54 stores in the Midwest and western states, most recently opening shop in Norman, Okla., and Temple, Texas.

The filing with the Securities and Exchange Commission says the company generated $264 million in the last fiscal year ended Sept. 30. The company posted net income of $4 million in the first six months of this fiscal year, up 86 percent from the same period 12 months earlier.

While organic food and beverages accounted for only 4 percent of sales nationwide in 2010, according to the Organic Trade Association, the growth has been strong. Between 1990 and 2010, annual organic product sales have grown from $1 billion to $26.7 billion. Last year that number jumped to $31.4 billion.