Peat Moss in the Garden – Sphagnum Peat Moss Uses

Peat Moss: What It Is and How To Use It In Your Garden

If you love gardening, chances are you come across references to peat moss on a fairly regular basis. Peat moss has several practical uses in the garden, from starting seeds to improving your soil, and is a useful amendment for both flower and vegetable gardeners.​

If you’re anything like me, you are willing to put in the time and effort to make your gardens as productive and healthy as possible.

Part of that process is understanding the various soil amendments and planting mediums available, which means that you need to be aware of the benefits, downsides, and practical uses of sphagnum peat moss.​

What Is Peat Moss?

So what is peat moss, anyway? The dark brown, compact matter that we recognize as peat moss is a far cry from the organic material’s origins. Peat moss is the decomposed remains of sphagnum moss and other living things that forms a dead, fibrous material over the course millennia in peat bogs around the world.​

Unlike compost, peat moss forms in the absence of air. This slows the decomposition process and creates a homogeneous material that is highly absorbent, which makes it very useful in the garden as a soil builder and a seed starter.​

Benefits of Peat Moss​

Peat moss is a unique organic material that provides gardeners with several benefits, including absorbency, compaction prevention, a sterile planting medium, and its acidic ph.​

The most important benefit of peat moss is the material’s absorbency. Peat moss retains water much better than average soils, which increases the absorbency of any potting mixes and garden soils that use peat moss.​

Not only is peat moss absorbent, it also does not compact, unlike other organic materials. Soil compaction is damaging to gardens and reduces water absorption and plant growth. Peat moss remains springy when it is wet and rehydrates easily, plus one application of peat moss can last for years.​

Peat moss is also a sterile planting medium, which means that it does not contain harmful pathogens or weed seeds. This, combined with its absorbency, makes it ideal for starting seedlings and is why peat moss is an essential component in most seed starting mixes.​

The pH of peat moss is slightly acidic. Acid loving plants like blueberries and camellias benefit greatly from peat moss applications, although plants that require neutral or basic pHs may not benefit from too much peat moss in the soil without additional, more alkaline amendments.​

Downsides Of Peat Moss​

As with most products, there are downsides associated with peat moss. The biggest is expense. While prices vary, peat moss is relatively expensive, especially if you plan on using large amounts. On the other hand, mixing your own potting soil can be cheaper than buying pre-mixed potting soil in the long run.​

Another downside is fertility. Peat moss has a relatively low nutrient content profile. It does contain some beneficial microorganisms naturally, and more can be introduced. As far as nutrient value, peat moss isn't high, but it isn't absolutely zero like many people believe. There is good evidence that there are both microorganisms in peat moss, as well as some level of nutrition, depending on the geographical origin and depth the peat moss was harvested from. For more info, click here.

The acidic PH of peat moss is beneficial to some plants but not beneficial to plants that prefer alkaline soils. For these plants, compost is a better peat moss alternative, as it has a more neutral or even alkaline PH, depending on the compost composition.​

Having a green thumb does not always translate to using environmentally green methods. Peat moss is a nonrenewable resource. Some gardeners have environmental concerns about peat moss that make it a poor choice for their gardens and is certainly an important factor to consider.​

How to Use Peat Moss in the Garden

Peat Moss in a Square Foot Garden.

Peat Moss in a Square Foot Garden. source

So how, exactly, should you use peat moss, now that you know about the benefits and downsides of sphagnum peat moss? How to use peat moss in your garden depends on what you plan to use it for. Peat moss is useful as an additive in potting mixes, as a soil amendment, and in your vegetable garden.​

Peat moss is a great seed starting medium. It is sterile, absorbent, and the homogeneous material is easy to work with. This keeps the seed bed uniformly moist, aiding in germination. Most seed starting mixes contain peat moss, and you can make your own seed starting mix by mixing peat moss with other soils or by making a peat moss based potting soil and adding fertilizer and vermiculite.​

You can also use peat moss as a soil amendment. Dry, sandy soils benefit from adding peat moss to retain moisture, and peat moss improves drainage and prevents compaction in dry and wet soils alike.​

These qualities make peat moss particularly useful in vegetable gardens, where extremes of dry and wet can negatively impact the growth and production of vegetables. Just remember that too much peat moss can change the PH of the soil, so garden accordingly.​

Peat moss is a carbon rich material, which makes it a good source of carbon in compost piles. The moisture retaining quality of peat moss also reduces the need for frequent watering, which makes it doubly valuable. The only downsides of using peat moss in compost are the expense and the environmental concerns associated with sphagnum peat moss.​

Application

Properly applying peat moss to soil mixes and as an amendment is important for the success of your garden. You will apply it differently depending on how you plan to use it, but for all applications it is important to wet the peat moss before adding it into the soil.​

As A Soil Amendment​

You can apply peat moss in a 2:1 ratio as a soil amendment, with two parts soil to one part peat moss. Mix the peat moss into the top 12 inches of the soil along with any other amendments until the mixture is evenly distributed and plant into the freshly prepared ground.​

As A Seed Starter​

There are several ways to prepare a seed starting mix from peat moss. The mix you use will vary, depending on your preferences. Soilless seed mixes use peat moss as the base with equal parts horticultural grade perlite or vermiculite, and add small amounts of lime and fertilizer to lower the PH and give your seeds some plant food.​

Potting mixes with soil use equal parts soil, peat moss, and perlite or vermiculite, along with any other fertilizers or amendments the gardener wishes to add. Many gardeners experiment with seed starting mixes to find the one that works best for them, so don’t be afraid to play around with your ratios and amendments to find the perfect mix.​

Peat moss is also useful for container gardening, as it preserves moisture and gives your containers a good organic material to grow in. For containers, make sure you mix peat moss with adequate amounts of soil, compost, and fertilizers to keep your container gardens happy.​

There are organic peat moss products on the market if you garden organically, so check the label prior to purchasing. Peat moss spreaders are also useful for lawn applications, and can be rented from home and garden centers.​

Where To Buy Peat Moss​

Luckily for gardeners, peat moss is one of the most widely available garden supplies around. It is sold at most garden stores and home and garden centers like Lowes and Home Depot, and can also be ordered online from a variety of distributors. Look for sphagnum peat moss for sale in your area and compare prices to get the best deal. You can also buy bulk peat moss for large applications, which could give you a discount.​

Prices for peat moss vary depending on the manufacturer and the size of the bag. Most peat moss is sold by the cubic foot, which is helpful for determining how much you need to buy for direct application to your garden. Smaller bags are sold by the quart and are perfect for mixing small amounts of potting soil or adding peat moss to containers.​

Environmental Concerns Of Peat Moss​

Peat moss is a nonrenewable resource. The biological processes that create peat moss takes several millennia, with peat reserves growing less than a millimeter every year. Most of the peat moss available in North America is mined in Canada, where only 0.02 percent of peat bogs are harvested and the industry is strictly regulated.​

Still, groups like the International Peatland Society point out that mining peat moss is a carbon intensive process, and removing peat releases large amounts of carbon dioxide into the atmosphere and limits the ability of the peatland ecosystems to act as a carbon sink. This has negative implications for climate change.​

Peat Moss Alternatives​

There are peat moss alternatives if you have concerns about the price of peat moss or its environmental impact. Compost offers similar benefits to peat moss in the garden and is a completely renewable resource. It also has the added benefit of reducing waste around your home and cutting down on the amount of material that goes into our landfills.​

There are some important distinctions between peat moss and compost:​

Peat Moss

  • Expensive
  • Acidic PH
  • Few nutrients
  • Does not compact
  • Contains few microorganisms
  • Does not contain weed seeds

Compost

  • Usually free
  • Neutral or slightly alkaline PH
  • Rich in nutrients
  • May compact
  • Contains microorganisms
  • May contain weed seeds

Compost is a viable alternative to peat moss for gardeners who want to add organic material to their gardens. Compost improves the soil’s water holding capacity and aeration while adding important nutrients and microorganisms to the soil, and is usually free. As a compromise, some gardeners opt to use small amounts of peat moss in their seed starting soil mixes, as compost can contain weed seeds and pathogens if the pile does not reach the correct temperature.

Is Peat Moss Right For You?

The decision to use peat moss is up to you. While it is important to consider the environmental concerns and price of peat moss before investing, the benefits of peat moss and the value it can add to your soil means that the decision to use peat moss is entirely personal.​

To determine if peat moss is right for you, ask yourself the following questions:​

  • Am I using peat moss in a seed starting mix or in the soil?
  • Can my budget afford peat moss?
  • Do I have easy access to peat moss alternatives like compost?
  • What PH do my plants require?
  • Does my soil have trouble retaining moisture?​

Answering these questions will help you decide if peat moss is right for your gardening needs. Since peat moss is widely available in gardening stores, you won’t have far to go to find it. Just remember to wear a face mask when handling dry peat moss as the fine material is easily inhaled.

If you have any questions, don’t hesitate to ask us questions in the comments section below.

This post was last updated on
  • KayEhm

    Green Moss is GREAT when it comes to gardening if you want to keep plants moist and cool, and control water absorption. I recommend purchasing wholesale green moss from http://www.willametteevergreen.com if you want to put these properties to good use.

  • albert

    can I use 100% peat moss for seeding?

  • Tsering Dhundup

    how long exactly does peat moss remain functional in a single usage? 2 3 or more than three years?

    • As far as I know it will last quite a while, especially if you consider that it is formed in bogs over thousands of years! But you may want to change it out for different reasons!