How green do those roses grow?

Nothing says love like fresh, blooming rose … but at what cost to the environment?

How are those flowers grown?

Where do they come from?

And how eco-friendly is it to buy a bunch of hothouse flowers out of season anyway?

About 70% of all cut flowers sold in the U.S. are imported. Most come from Colombia and Ecuador.

Unfortunately, Latin American flower growers use a lot of chemicals on their products, including pesticides that have long been banned in our country.

The Natural Resources Defense Council notes that roses have been found with more than 50 times the pesticide residues allowed in food. Florists who handle these flowers frequently develop dermatitis on their hands.

But those who suffer the worst are the farm workers themselves.

Studies in Ecuador, Colombia, and Costa Rica found that nervous system damage, genetic damage, miscarriages, premature births, and congenital deformities are all linked to chemical exposure in the flower industry. Plus, runoff from these pesticides pollutes the waterways due to lax environmental laws in South America.

So what about that bouquet? You do have some earth-friendly options for those you care about.

Look for organic, fair-trade, or sustainable -- ideally, you'd get a flower that's all three, but that's admittedly tough to find. But any one of these will be better for the planet than a generic bloom.

You can buy flowers that are certified USDA organic. Look for the same "organic" logo that you already find on foods.

TransFair has begun certifying fair-trade flowers. The fair-trade label guarantees that workers get decent wages and the products are grown in an environmentally responsible manner.

Another label to watch for is VeriFlora. This program certifies that flowers are sustainably grown with fair labor practices, and if they're not organic, the grower is on the path to becoming organic. Certification is conducted by a recognized neutral third party.

Where can you buy flowers with any of these labels? Ask your local florist to start carrying certified roses. Also, supermarkets like Trader Joe's and Safeway now carry VeriFlora-certified flowers, plus Whole Foods may sell organic flowers. Sam's Club has fair-trade certified roses. The specific selection varies depending on your location.

You can order online for holidays and special events at various sites. All of the roses at Organic Bouquet and Organic Style are VeriFlora-certified and some are certified organic.

The "planet-friendly" section of 1-800-Flowers features organic and fair-trade bouquets and gift baskets including one bunch of fair-trade certified roses.

FTD has a "go green living" section with flowers described as 'certified sustainably grown,' but the site doesn't say where the certification comes from. When I called the 800 number, nobody could tell me more about this issue, so I'm not sure if this is green-washing or legitimate.

For more certified organic flowers, visit Diamond Organics and California Organic Flowers, or search Local Harvest for a farm near you.

If you can find local flowers, do buy them. But while so many of our cut flowers are imported, florists note that those roses are shipped in the cargo holds of passenger jets which would already be making the trip. Fragile plants can't exactly go in container ships like other imports. Thus, it's hard to say how they're adding to your carbon footprint.

The best way to show you love the planet and your loved one is with greener blooms. Organic, fair-trade, or sustainable roses help everyone enjoy the sweet scent a bit more.