4f54397257a1210d78ef3d52403fb3b2

What’s in the potting soil that you are using?

Chances are, if you are like most gardeners, you don’t really know. It’s dark brown, it’s moist and it looks like, well... potting soil. But, if you’re concerned about sustainability, global climate change and the environment, you might want to take a closer look in that bag.

rvanderhoff

The majority of potting soils, contain peat moss as their primary ingredient and that’s where the issues begin for a lot of environmentalists and a growing cadre of concerned gardeners.

If you’ve been a gardener for long, you are likely familiar with peat moss, but may not know about its associated environmental issues. Peat moss is the decaying plant matter that forms under sphagnum moss. As sphagnum moss grows, it layers upon itself, collecting and compacting dead matter beneath the living layer. Very slowly, the peat layer builds as more moss grows overtop, creating the rich, earthy, substance known as peat moss. Although devoid of nutrition or healthy biological microorganisms, it is a popular ingredient in most potting soils and some soil amendments.

What are the issues and why go peat free?

First, peat renews at a very, very slow rate. Since it is organic matter, many people assume that peat is a renewable resource. Technically, it is, since the moss is a life form that continues to grow. The problem is that it grows at a very, very slow rate - only 1 to 2 millimeters a year. This has lead to many debates about the renewable aspects of peat harvesting. A thousand years of peat growth is easily harvested in a week. Adding to the problem is the location of this peat resource.

Peat_Harvesting_8-7-10

Sphagnum moss only grows in northern bogs or wetlands. About 90% of the peat that is used in North America comes from commercially mined Canadian peat bogs. Peat sustains many Canadian wetlands due to its water absorbency (the same reason soil companies use it in their potting mixes) and when mass harvested, this ecosystem is eliminated.

The mining process involves digging a network of ditches and basins around and through the bog, then draining the water away from the wetland, causing the area to dry out and die. Once that happens, the surface plants are removed and the peat harvesting begins.

The second big concern is that peat bogs store carbon, lots of carbon; and that’s a big issue among global warming scientists. Although they cover only 3% of the world’s land area, peatlands contain almost 30% of all the carbon stored on the earth’s lands. Of course, the release of carbon into our atmosphere is the primary cause of global warming. The more peat we harvest, the more carbon we put into our atmosphere and the more global warming.

How exactly does peat moss fight global warming? Well, as the mosses grow, they absorb carbon dioxide, which becomes locked up within the plants structure and remains there as the plants decay and turn to peat. Scientists think that peat bogs contain more carbon than all the world’s tropical rainforests combined. Each square yard of a peat bog may contain several hundred pounds of undecomposed organic matter, for a total of between 200 and 450 billion tons of carbon stored away in peat bogs worldwide. But when the bogs are disturbed or drained for peat extraction, the peat starts to decompose and the carbon dioxide is released back into the atmosphere, where it acts as a potent greenhouse gas, trapping heat; much like the burning of fossil fuels.

Third, peat bogs are home to a large array of flora and fauna that thrive in these unique environments.

Although a small amount of peat is used as fuel in Europe, in the U.S., peat moss is almost exclusively used in horticulture. 40,000 acres of peat moss are currently being harvested in Canada, with 90% of the product destined for the gardening industry. Many conservationists, gardeners, and wetlands scientists are now recommending a boycott of peat. England’s famous Royal Horticultural Society has targeted a  90% reduction of its own peat use by the end of this year and the England’s government has set aggressive targets toward a huge reduction in peat consumption. England’s largest retailers of peat moss, companies similar to our own Home Depot and Lowe’s, have agreed to meet or exceed these targets. Bravo!

Yet in the U.S. the peat moss debate has barely reached a whisper. If I’ve piqued your interest, I encourage you to do a little more research and then make your own decisions about your consumption of peat moss.

Next time you’re picking up one of those potting soil bags, flip it over and take a look at the ingredients. It might be worth knowing what’s in the bag.

Ron Vanderhoff is the Nursery Manager at Roger’s Gardens, Corona del Mar.

Questions from Readers August 8.

Did you notice that the Costa Mesa Sanitary District is offering residents Earth Machine compost bins for only $20.  I looked it up and found it selling for $100. I picked up one today and it seems sturdy and well designed. They seem to have a good supply and have more on order. Your readers might want to know about this.  Information is available at www.cmsdca.gov or by calling the Costa Mesa Sanitary District office at (949) 645-8400.

Van Wright, Costa Mesa

Answer:

Thanks for the tip Van and good timing, considering the topic of this week’s column.

Assembly_7-24-10_4

Plant Care Reminders

Stag Horn Fern Care and Propagation
Ferns Walter Andersen Nursery

Stag Horn Ferns (Platyceriums) - Care and Propagating

Planting and Mounting
Star Jasmine Monthly Plant Care
Vines Steve Brigham

Jasmine - Star (Trachelospermum jasminoides) - Monthly Plant Care Calendar

You can have these monthly Plant Care Reminders sent directly to you each month!

Plant Care Reminders - Herbs - Sunset…

7124 Mr. Mitch
Dill
Do you live In coastal southern California? Do you grow any of these Herbs?

Poppy - California (Eschscholzia…

29558 Coastal Sage Gardening
California Poppy Monthly Plant Care
You can have these monthly Plant Care Reminders sent directly to you each month!

Hibiscus - Blue (Alyogyne huegelii) -…

5375 Steve Brigham
Blue Hibiscus Montly Plant Care
You can have these monthly Plant Care Reminders sent directly to you each month!

Gardening Articles

Plants Crossword Puzzle
Crossword Puzzles Garry Shirts

Puzzle #4 - Plants & Such

Print this and take a few minutes and have some fun trying to figure this crossword puzzle out. Let us know if you have any suggestions for new puzzles. Be sure not to peek!
Cucumber Seedlings
Seeds Chris Eirschele

How to Start Seeds When Living in Cold Climates

Growing plants by starting them from seeds is one way to economically garden.

APLD International Landscape Design Gold Award Winner: Matthew Cunningham

2861
Le Petit Chalet Makeover
APLD Names 2011 Landscape Designer of the Year

Patrick Anderson - Southwest

18095
Patrick Anderson
Region: Southwest

Some Gardening Traditions just aren’t “in” Anymore

4808
Better Gardening Practices
In case I forget for a mere nanosecond, my two daughters will quickly remind me that my…

Plant Recommendations

Heteromeles arbutifolia
Plant Recommendations Connie Beck

Trees and Large Shrubs - Southern California

Connie Beck's Top Plant Recommendation: Favorite Trees and Large Shrubs for Southern California.
Agonis flexuosa 'Jervis Bay After Dark'
Plant Recommendations Bill Teague

Australian Trees - Southern California

Bill Teague's Top Plant Recommendations: Favorite Australian Trees for Southern California.

Yellow: A Color Well Worth Considering

4267 Christiane Holmquist
Flannel Bush
Of the many colors I try in my garden yellow is one I gravitate to again and again.

Ivies for Small Moss Filled Topiary -…

11026 Pat Hammer
Hedera helix 'Lady Frances'
Pat Hammer's Top Plant Recommendation: Favorite Ivies for Small Moss Filled Topiary in…

Featured Plant Care

Blue Bunny Hydrangea monthly plant care

Hydrangea - Blue Bunny (Hydrangea involucrata 'Wim Rutten' ) - Monthly Plant Care Calendar

in Shrubs
You can have these monthly Plant Care Reminders sent directly to you each month!
Zuchinni Monthly Plant Care

Zuchinni Squash - (Cucurbita pepo 'Zucchini') - Monthly Plant Care Calendar

in Edibles
You can have these monthly Plant Care Reminders sent directly to you each month!
Phormium Monthly Plant Care

Flax - New Zealand (Phormium spp.) - Monthly Plant Care Calendar

You can have these monthly Plant Care Reminders sent directly to you each month!
Grevillea banksii Monthly Plant Care

Grevillea - Red Silky Oak (Grevillea banksii) - Monthly Plant Care Calendar

in Shrubs
You can have these monthly Plant Care Reminders sent directly to you each month!

Latest Articles

Six things for your indoor plants during winter

Do These Six Things to Keep Indoor Plants Healthy During Winter

Winter has hit southern California along with the rest of the U.S. No polar vortex here,…
Gardening Professionals and Clubs

Gardening Pros & Clubs: Using the Great Features on the Mulch

We'd like to help connect gardening professional and home gardeners. We've designed a…
Star Jasmine Monthly Plant Care

Jasmine - Star (Trachelospermum jasminoides) - Monthly Plant Care Calendar

in Vines
You can have these monthly Plant Care Reminders sent directly to you each month!
Bababerry Raspberry Monthly Plant Care

Raspberry - Bababerry (Rubus idaeus 'Bababerry') - Monthly Plant Care Calendar

in Edibles
You can have these monthly Plant Care Reminders sent directly to you each month!

Popular Articles

Baseball Field Maintenance

Baseball Field Maintenance - A General Guide for Fields of All Levels

in Lawn
More great baseball field resources can be found here (including a pdf version of this…
Queen Palm Care & Use

The Queen Palm (Syagrus romanzoffiana) Care & Use

in Trees
Jungle Music Palms and Cycads is a family owned and operated business established in 1977
Microgreens

What are Microgreens and How to Grow Them

in Edibles
Microgreens are tiny leafed vegetables that are grown from seed and require very little…
Kahili Ginger Plant Care

Hedychium gardnerianum (Kahili Ginger) - Monthly Plant Care Calendar

You can have these monthly Plant Care Reminders sent directly to you each month!

User Guides (Slide)

Popular Recommendations (Slide)