Peat moss is a gardening component that many people like to use to increase their soil’s acidity or improve its ability to hold onto moisture. The moss is a particular kind of growth native to certain regions of the world which contains peat. Since peat moss use far exceeds its production, many gardeners look for ways to replace it with viable alternatives. Some are better than others, depending on what people are hoping to get from the soil. By considering these approaches, gardeners can minimize their consumption of peat moss and continue to maintain healthy gardens.
Why Use Peat Moss Alternatives
While many gardeners are familiar with the use of peat moss in various gardening endeavors, they may not be aware of the cost of using it. Unlike using coconut coir, compost, or bark mulch to increase drainage or improve moisture retention in soil, peat moss is not particularly sustainable. To harvest it, someone has to scrape off the top layer of moss from ancient bogs in certain parts of the world, largely in Canada. It takes as long as centuries to rebuild the moss once it has been scraped away.
Unfortunately, for what it does, peat moss is also not necessarily the best tool for the job. The peat moss is natural but not reusable, so gardeners have to buy it over and over again. It compacts the soil in a garden, which can make oxygenation more difficult. Peat moss is also fairly acidic, which means that some plants require additional amendments to be able to grow in it.
Why Peat Moss Is Effective (and What to Look for in Alternatives)
Despite its drawbacks, peat moss continues to be one of the most popular soil components for gardeners, particularly those who use containers. The product is expensive, but for a person’s investment, they get a soil component that is:
- Lighter than topsoil
- Free draining once the peat has absorbed all the water it can
- Nutrient-dense, although this depends on the nutrients of the source
- Lightly acidic, which is ideal for many container plants
As such, people who are looking for alternatives to peat moss need to make sure that they can still check most or all of these boxes in other ways. In many cases, they will need to use more than one product. For example, someone who uses LECA to improve drainage with other soil may need to add compost or bark mulch on top to provide added nutrients.
One of the most natural and sustainable alternatives to peat moss is organic compost. Although gardeners may be able to purchase compost locally, they might also choose to generate it themselves. Compost is a combination of yard waste and decomposing food. When layered together properly and allowed to decompose over a period of a few months, it creates organic matter rich in nutrients that plants need. It can be difficult for inexperienced people to make at first, but may eventually provide a virtually unlimited amount of compost for gardening.
Compost is ideal as a replacement to peat moss because of its ability to retain moisture and its natural acidity. Peat moss tends to be acidic, with a soil pH around 3 to 6. Compost, through the process by which micro-organisms break down organic particles into nitrogen, also has a pH more acidic the neutral. As such, gardeners may be able to mix the compost in with the rest of their soil much in the same way they would peat moss. If they would need to increase the alkalinity of the soil by adding limestone to suit a particular plant when using peat moss, they would take a similar approach with compost.
Compost is rich, very dark in color, and contains a sour odor. People producing their own compost (which can even be done in the kitchen with an electric countertop composter) will know that it is ready for use when it meets these requirements. Gardeners have a few options in the ways that they can incorporate compost as part of their planting or garden maintenance routine:
- Sprinkle compost on top of soil
- Rake compost into freshly tilled garden beds
- Mix compost into soil for potting
Compost has a high nutrient density, but those nutrients will decrease over time. As such, people may need to apply compost more than once a year to achieve the best results.
Coconut coir offers a material that is easy to renew and features many of the benefits of peat moss. The coir is the dry, stringy or husky pieces on the exterior of a coconut. Coconut growers used to throw away this byproduct. Over time, people began to realize that the fibrous pieces can provide nutrients for plants, as well as helping to maintain an ideal moisture environment for growing. The manufacturing process to create the coir can significantly affect its quality. Gardeners who are willing to seek out high-quality products may be able to use them as an effective replacement for peat moss without compromising plant health.
Creating coir for sale is a process that can take up to several weeks. Growers start with the byproduct they get from husking coconuts grown for consumption. These husky pieces are soaked in water and separated based on their size, quality, and type. The smallest pieces may be pressed and hardened into disks that gardeners can use in place of peat pots. Larger pieces can serve as a replacement for bark mulch, commonly placed on top of garden soil. The pieces of sizes in between can be pressed into a brick or kept loose as a soil replacement.
High-quality coconut coir is an effective component of soil. Gardeners may choose to mix it in with their existing soil, much as they would perlite. Since coir is natural, it will biodegrade unlike these other materials. Unfortunately, the quality of the coir is an important aspect that people must research before buying. Some products have a high sodium content from being soaked in salt water. Others may bring harmful pests because they were not treated before packaging. People should investigate and stick with brands that they know are reliable.
Gardeners have been using wood products to improve the quality of their soil for centuries. For example, it is quite common for people to top fresh or treated soil with a layer of organic matter and another layer of wood mulch. Wood products, particularly those that are partially decomposed, can be effective at moisture retention without compromising drainage capability. People can use:
- Small pieces of wood
- Bark mulch
The type of wood is an important choice, since many species of trees are also limited in supply. As a general rule, gardeners should plan to select wood that is sustainably grown and easy to find close to the gardening site. Some people may want to mulch their own wood from the garden and use it as a way to recycle old growth in favor of new. The wood products must come from untreated wood because treated wood often contains chemicals that can be toxic to plants and animals.
Certain types of wood, like pine bark, can be an ideal replacement for peat moss given their nutrient content. Peat is a common addition to gardens that have a naturally higher soil pH, given the peat’s higher acid content. Many wood species are also slightly acidic. People should take care in the quantity of wood that they add to their soil, however. Plants that need a higher moisture content may not be able to absorb as much water from wood, which is lighter and drains more quickly than peat. In this case, it may be worth using a combination of peat moss alternatives, like wood mulch, coconut coir, and LECA. A moisture meter may help gardeners understand how effective this solution is.
LECA, or lightweight expanded clay aggregate, is an interesting man-made approach to replacing peat moss in gardening. In essence, LECA is a collection of manufactured balls of clay that will expand in water. Gardeners may not want to use it for gardening applications directly in the soil outside. Rather, they may be more likely to take advantage of it for a raised bed garden or indoor planting.
Since the clay is manufactured and dried, people should not count on it providing nutrients for the plants to thrive. Its primary function is to manage moisture content and drainage for a pot. For example, many indoor plants have a need for higher moisture content. If gardeners use peat moss, the soil may decrease aeration. Insufficient aeration or excess moisture retention of the soil can lead to root rot, which is a common cause of poor health in a plant or growth failure. Pooling water in the pot can also draw pests and promote fungal growth.
People can use the clay balls as a replacement for most or all of the soil, depending on the plant. Because the balls absorb water, they create a reasonable environment for plants to absorb that water through the roots over time. Since they do not completely dissolve in water, they allow free drainage in the gaps between the balls. That helps to ensure that the roots are never sitting in standing water. Gardeners should keep in mind that this soil alternative contains no nutrients. They will need to add everything the plant needs through a feeding mechanism, fertilizer, or other soil alternative.
As with many other approaches to gardening, what works for one person might not work as well for others. Gardening is heavily dependent on the climate, the options that people have for soil in the area, and what they would like to grow. In many cases, gardeners will need to use a variety of soil components to effectively replace the benefits they get from peat moss. Having the right information and being willing to try out new things will help people to determine which ones are the most effective for them, without feeling pushed to make any particular choice.