Peat Moss And Gardening – Information About Sphagnum Peat Moss
By: Jackie Carroll
Peat moss first became available to gardeners in the mid-1900s, and since then it has revolutionized the way we grow plants. It has a remarkable ability to manage water efficiently and hold on to nutrients that would otherwise leach out of the soil. While performing these amazing tasks, it also improves the texture and consistency of the soil. Keep reading to learn more about peat moss uses.
What is Peat Moss?
Peat moss is dead fibrous material that forms when mosses and other living material decompose in peat bogs. The difference between peat moss and the compost gardeners make in their backyard is that peat moss is composed mostly of moss, and the decomposition happens without the presence of air, slowing the rate of decomposition. It takes several millennia for peat moss to form, and peat bogs gain less than a millimeter in depth every year. Since the process is so slow, peat moss isn’t considered a renewable resource.
Most of the peat moss used in the United States comes from remote bogs in Canada. There is considerable controversy surrounding the mining of peat moss. Even though the mining is regulated, and only 0.02 percent of the reserves are available for harvest, groups such as the International Peat Society point out that the mining process releases massive amounts of carbon into the atmosphere, and the bogs continue to exhale carbon long after the mining concludes.
Peat Moss Uses
Gardeners use peat moss mainly as a soil amendment or ingredient in potting soil. It has an acid pH, so it’s ideal for acid loving plants, such as blueberries and camellias. For plants that like a more alkaline soil, compost may be a better choice. Since it doesn’t compact or break down readily, one application of peat moss lasts for several years. Peat moss doesn’t contain harmful microorganisms or weed seeds that you may find in poorly processed compost.
Peat moss is an important component of most potting soils and seed starting mediums. It holds several times its weight in moisture, and releases the moisture to the plants roots as needed. It also holds onto nutrients so that they aren’t rinsed out of the soil when you water the plant. Peat moss alone does not make a good potting medium. It must be mixed with other ingredients to make up between one-third to two-thirds of the total volume of the mix.
Peat moss is sometimes called sphagnum peat moss because much of the dead material in a peat bog comes from sphagnum moss that grew on top of the bog. Don’t confuse sphagnum peat moss with sphagnum moss, which is made up of long, fibrous strands of plant material. Florists use sphagnum moss to line wire baskets or add a decorative touch to potted plants.
Peat Moss and Gardening
Many people feel a twinge of guilt when they use peat moss in their gardening projects because of environmental concerns. Proponents on both sides of the issue make a strong case about the ethics of using peat moss in the garden, but only you can decide whether the concerns outweigh the benefits in your garden.
As a compromise, consider using peat moss sparingly for projects like starting seeds and making potting mix. For large projects, such as amending garden soil, use compost instead.
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Peat Moss in a Vegetable Garden
Peat moss is an old stand-by in the garden. The fluffy material has been favored as an organic soil amendment for many decades. There are, however, some peat moss naysayers. The truth is, if you want to use peat moss in the vegetable garden, there are a few factors to take into consideration.
What is peat moss?
When we’re talking about peat moss for gardening, at least in the US, we’re talking about sphagnum peat moss. Sphagnum is a type of moss that’s most notable for its amazing absorption ability, capable of taking in 20 times as much water by weight as the moss’s dry weight. It’s basically a natural sponge. Sphagnum moss prefers growing in moist tundra-type areas, and most of what gets used for gardening comes from peat bogs in northern Canada. As the sphagnum moss dies in these bogs, it very slowly decays into what becomes the peat moss that's so popular for gardening.
Peat Moss Cow Manure Fall leaves What Should You Put in Your Beds
Peat Moss? Cow Manure? Fall leaves? What Should You Put in Your Beds?
Q. I'm making raised beds for my veggies four feet wide, as you've suggested. I've filled them with soil and was wondering about amendments. Thus far I've added peat moss and composted cow manure. Do you recommend adding perlite and vermiculite? I'm also tilling in some double-shredded leaves. Is this OK?
Now, shredded leaves are great and double shredded leaves are twice as good. If I were a better man, I'd double shred my leaves, but with deadlines and advancing age I'm happy to get them shredded once. I'll use most of those shredded leaves for compost making and some as a mulch directly on top of my raised beds. But I won't till any into my soil!
The first reason is the tilling itself. While tilling or double-digging is necessary to loosen up the soil when you first make your raised beds, we want to avoid tilling them afterwards, as tilling causes soil nutrients to be lost and brings weed seeds to the surface. (For details, see our 'no-till' articles.)
And one of the biggest benefits of building raised beds is that you create a defined area that you'll never have to step into. No stepping means no soil compaction the soil in your beds stays naturally light and loose and doesn't need tilling. Henry did one big thing right when he made his beds the recommended four feet wide, because that allows him to reach the centers without stepping inside the framed area. But what he tilled into that framed area could cause serious problems.
Now: There is a long history of tilling in amendments like compost and mushroom soil so that they become well-mixed with the native soil. And cover crops have to be tilled back into the soil to make use of the nutrients in their 'green manure' bio-mass. But compost and mushroom soil are pretty much the same as soil and cover crops provide mostly nitrogen. But leaves are all carbon. And carbon ties up soil nitrogen and makes it unavailable to plants.
The only worse thing would be to till wood chips into the soil. Their large particle size means they would take years to break down. The much smaller particles of double-shredded leaves are going to be much easier to remediate. And yes, we can remediate this problem.
But not with cow manure! You have to assume that modern bagged manure is collected from factory farms, where the cows are heavily medicated and fed genetically engineered crops that were sprayed heavily with systemic herbicides. And because these herbicides are systemic—meaning that they're absorbed into the genetically engineered plants—the manure (and meat and milk) is going to contain herbicide residues. And although cow manure is nutritionally balanced, it's also kind of 'cold' it doesn't contain a lot of any of the basic plant nutrients. And the nutrient needed here is nitrogen to balance out the carbon in all those leaves.
Years ago, the answer would have been composted horse manure. It's very nitrogen-rich. But many modern chemical herbicides are so persistent that they survive the composting process even if the animals the manure came from were just grazing on 'regular' sprayed fields. (You'll find lots of warnings about herbicide contamination in horse manure at State Extension websites.)
So I'm going out for coffee instead. Used coffee grounds are widely available, and high in nitrogen. Yes, they're also acidic, but so is the peat moss he used—which was also a bad idea. Peat moss is great for acid-loving plants like blueberries, azaleas and rhododendrons, but not for vegetable beds. So Henry already needs to mix some wood ash or lime into his beds to neutralize that acidity, and with the coffee grounds he's just going to need to use a little more.
And I'm afraid these new amendments will have to be tilled in. Because the peat and leaves were tilled in, any balancing amendments will need to be tilled in as well. So my advice is to collect grounds from local coffee shops, mix some wood ash or lime in with them and till it all into the soil. And since we're already tilling, yes—add some perlite or vermiculite in there as you go these natural minerals are great at loosening up heavy soils and making it easier for plants to get air around their roots.
Now: how much of each thing?
You really can't use too much perlite or vermiculite they don't change the soil pH or its nutrient balance and the volume of coffee grounds and wood ash is going to depend on the initial amount of leaves and peat moss he used. This is where you have to use your best instincts, let it all settle out and then test the soil to see where you are with the pH. You can test it this fall to get a basic idea, but you'll get a more accurate reading in the Spring, after things have settled in together. (And of course, your first year crops will tell the ultimate tale!)
And in the future, only add amendments to the surface of your beds: An inch or two of compost a season to keep the soil fertile and an inch or two of shredded leaves to keep down weeds and attract earthworms.
The benefits of peat moss in the garden
Peat moss is a wonderful natural organic way to condition the soil and give it nutrients, but knowing how to mix it well with other ingredients to get the proper growth from your specific vegetables and plants is very important. Don’t just go crazy throwing peat moss all over the garden and think it will do the job on its own. You have to put some thought into it and do the research first. When used alone, peat moss can destroy a healthy garden, but with additives, it can be your friend. Most gardeners play it safe and only use it for seed starting. Or to give a single seed a head start on its journey to grow strong. Use equal parts peat moss, perlite, vermiculite and compost to create small little mounds for your seeds. A bit of wood ash should be thrown into the mix to counteract the acidity.
Know how much to use
Depending on how big your batch is, you only need a few tablespoons of the wood ash. I would say two tablespoons for a big batch and for a barrel full use a quarter of a cup. I use old egg cartons to store each individual mound, but you can even use ice trays as well. When using peat moss in the garden, it would help if you tested your soil first, because depending on what area you live in, your soil may be more acidic and using peat moss would be disastrous. If you live in an area where your soil is more alkaline, then peat moss could balance the PH and enhance your garden.
No matter where you live in the world, you can create the unique kind of atmosphere. One that your plants need and create a special soil mixture for plant beds. You can make raised flower beds or have your vegetables grow in a special place inside your home. We have so many options now, thanks to businesses like Aerogarden and hydroponics. Costco even sells greenhouses for various prices. Find something that fits your lifestyle and budget.