Stroll around a typical home-goods store and you might feel as though you’re walking outdoors – everything is turning green. Over the past year, more mainstream companies have jumped on the green bandwagon, unveiling “natural” cleaners, recycled products and packaging, sustainably made furniture, and housewares aimed at a growing market niche: the green consumer.

Wal-Mart, for instance, is stocking shelves with organic cotton towels and Clorox’s latest cleaning line, Green Works.

Walk into Crate & Barrel, and you’ll probably notice chairs made of sustainable wood, teak dining collections, and a shopping environment with a low-energy lighting system.

Companies are realizing that going green – or at least sprinkling some green into their mix of conventional products – is good business. Indeed, American consumers are expected to double their spending on eco­friendly products and services in the next year to an estimated $500 billion, according to Landor Associates.

“I find myself weighing a green purchase versus a regular purchase, and there were many times in the past when price would have made the decision for me,” says Leah Ingram of New Hope, Pa., whose blog, The Lean Green Family, chronicles her family’s transition to a greener lifestyle. “Now that I’m more aware of [the environment], I’m willing to spend a little more.”

Yet it’s unclear how much of an impact all this green buying will actually have on the environment. Purchasing anything, regardless of how green it is, adds something to a person’s carbon footprint. And concern is growing over “greenwashing” – or misleading claims made by companies about the environmental benefits of their products.

“There’s so much greenwashing going on. It can be frustrating to find out which companies are really green,” says Amy Todisco, owner of GreenLivingNow.com, an online natural products store in Huntington, Vt. “When you find out that [some brands] are not doing what we thought they were doing, it’s very disheartening.”

Ms. Todisco has been researching products like laundry detergent, cleaning supplies, and personal-care items for more than 14 years. She’s found that many that are marketed as “natural” still use synthetic ingredients.

One of the challenges for consumers is that there are no uniform standards for “green,” says Celia Lehrman, deputy home editor of Consumer Reports.

As a result, products are appearing on store shelves in shades of green. One company may remove or substitute a few ingredients and call the result ecofriendly when, in fact, its product still contains traces of harmful elements. Another company may take an approach in which everything from materials to packaging to distribution is designed to be as ecofriendly as possible.

While this is the ideal, it can get complicated and expensive in a global economy, says Ed Stafford, an associate professor of marketing at Utah State University who has studied green marketing.

Ms. Lehrman suggests that consumers look for third-party certification on products. (See below.)

One area consumers aren’t likely to overlook in deciding on a product is performance, says Dr. Stafford. If a company decides to go green, its product has to be as good as the nongreen product. “The bottom line is, we don’t buy carpet cleaner to save the planet. We buy it to clean our carpets.”

Testing of green and energy-efficient products has shown that performance is improving on the whole, Lehrman says, although she advises checking the Consumer Reports website for specific product reviews.

Sometimes, just refraining from buying anything is the greenest choice a consumer can make, experts say. “If you need something new, you have to weigh the whole life-cycle cost of the product and decide whether or not you’re really helping the environment by buying something,” Lehrman says, citing $400 organic sheets as an example. “Is it better to just not buy new sheets?”

“Buy less, buy better, and when possible, buy local,” advises Maxwell Gillingham-Ryan, creator of “Apartment Therapy,” a book and website that encourages green living. He advocates “editing” your home, buying only what you really need.

“The whole green mantra is ‘reduce, reuse, and recycle.’ It’s not ‘shop,’ ” says Linda Hunter, author of “Green Clean,” a guide to green cleaning solutions.

But trying to transform your entire home into a green one overnight can seem daunting, says Ms. Ingram. “You have to take it step by step. I can’t change everything about how I live, but ... if you just take it a little at a time, it won’t feel so overwhelming.”

How to tell if a product is really green

When you’re buying green products for your home, checking the label isn’t enough, consumer advocates say. It’s better to check for third-party certification. Some common ones:

• Designed for the Environment – Introduced by the US Envir­onmental Protection Agency (EPA) to indicate that products contain environmentally preferable ingredients.

• Green Seal – Aims to reduce the environmental impacts tied to the use, manufacture, and disposal of products and services.

• Energy Star – An EPA certification whose goal is to reduce greenhouse gas emissions through energy efficiency.

• Water Sense – It certifies water-efficient products such as faucets and toilets.

• Forest Stewardship Council – Products that bear the FSC logo are guaranteed to contain wood or wood products harvested from a certified, well-managed forest.

• Leadership in Energy and Environmental Design (LEED) – Promotes sustainable site development, water savings, energy efficiency, sustainable materials selection, and indoor environmental quality.

For more details on eco-labels and ways to go green at home, check the guides on these websites: a Consumer Reports site that includes definitions of eco terms; Treehugger's How to Go Green Guides; and the Organic Consumers Association.