How to Create Black Gold for Your Garden Soil

Young Woman Recycling Dried Leaves in the Composter, Slovenia, Europe

Neyya / Getty Images

Project Overview
  • Working Time: 2 - 3 hrs
  • Total Time: 6 - 8 wks
  • Skill Level: Beginner

Compost is the poster child for organic matter. It is the end product of the decomposition of organic matter. It can be any kind of organic matter, which includes garden waste, kitchen scraps, leaves, grass clippings, straw, even manure.

Compost is not particularly high in essential nutrients, (N-P-K), and is considered a soil conditioner rather than a fertilizer, but it creates better soil and makes nutrients more accessible to plants. Compost can also:

  • Improve soil structure
  • Aid in necessary microbial activity in the soil
  • Attract beneficial insects such as earthworms
  • Suppress several soil-born diseases
  • Hold nutrients in organic or slow-release form, allowing for availability throughout the growing season

By the time the compost cooking process is complete, weed seeds, fungus spores, and other undesirable elements that may have gone into your compost bin should no longer be viable. Finished compost looks like rich soil. It’s dark and crumbly with an earthy smell.

What You'll Need

Equipment / Tools

  • Garden hoe or rake
  • Tarp

Materials

  • Compost bin (optional)
  • Brown and green matter for compost

Instructions

While there are many methods of composting and many composting bin styles, there is no best method. The important thing to remember is that you can never add too much compost to your soil.

There are two basic approaches to making your own compost: active and passive:

Passive composting is the "Compost Happens" school. All you need to do is pile up your organic matter and wait. It can take a few years to fully decompose, but eventually, it will. However, it may never heat up enough to kill off weed seeds and spores.

Active composting requires varying degrees of effort. Truly active composting involves being somewhat precise with the layers you add to your compost pile and turning it regularly. Here's how.

  1. Choose Your Bin or Pile

    Make a pile of the compost material or keep things neater with a bin that is at least 3 feet by 3 feet.

  2. Add the Layers

    Start with a 3 to 6-inch layer of brown material such as hay, straw, or dry leaves. On top of this, add a layer of up to 18 inches of green material such as plant debris, kitchen scraps, and grass clippings on top of the brown layer.

    Any type of organic material that has not been treated with herbicides or pesticides can go into your compost. Some common materials include:

    Green Material (N) - Coffee grounds, garden trimmings, prunings, grass clippings, hair, kitchen scraps, rotted manure, seaweed, and tea leaves.

    Brown Material (C) - Cardboard, corn cobs and stalks, leaves, newspaper, shredded paper, pine needles, sawdust, straw or hay, and wood ash.

    Add eggshells, which are neither green nor brown, but still add some calcium to the mix.

    Tip

    While it is advised that you keep weeds, especially perennial weeds, pesticide-treated material, and diseased plants out of your compost bin, almost every other form of plant material is fair game. Other materials to avoid include bones, meat and fish scraps, and pet manure.

  3. Water the Pile

    Water the pile until it is damp throughout, but not soaked.

  4. Add More Layers

    Repeat the layers until the compacted pile is at least 3 feet high. If it is smaller than 3 feet, it won't heat up enough to create compost.

  5. Turn the Pile

    Using a garden hoe or rake, turn the pile every couple of weeks to make sure it stays uniformly mixed.

  6. Cover the Pile

    When the pile reaches its full size, cover it with a tarp to keep the nutrients from washing away and to prevent it from getting too wet.

  7. Sift Through the Compost

    When it is crumbly and resembles soil more than debris, it's time to sift out the large pieces that have not yet decomposed and start using your compost.

  8. Repeat the Process

    Ideally, you'll have several compost piles going at once. One that is ready to use, one that is full and in the decomposing process, and finally one that you are still adding to.

    Tip

    As with anything in nature, there are a lot of variables, so there is no perfect method of composting. Three parts green to one part brown is a good rule of thumb to follow. However, if you're a "let it rot" kind of composter, you'll still end up with good compost.

What to Look for If You Are Purchasing Compost

You can buy compost by the bag or by the truckload. Either way, it's good to know the source.

Bagged Compost: The problem with bagged compost is that you don't really know what you're getting until you bring it home and open the bag. Many times compost by the bag is composted manure, which is usually fine. To be on the safe side, look for the word "organic" on the label. That would offer some guarantee that whatever ingredients were used were not contaminated or something you would not want in your garden, like sewage, heavy metals, or pesticides.

Bulk Compost: This is definitely the cheapest way to purchase compost. Just as important, you can see what you're getting before you get it home. Don't be afraid to ask what they are using to make their compost and if it is organic.

How to Use Compost

Compost can be added to your garden at any time, either turned into the soil or used as a mulch or top dressing for established plants. You can add it just before planting time or amend your beds in the fall and let the natural freezing and thawing process work it into the bed.

How much compost your soil needs will depend on the quality of the soil. The more you add, the better your soil will become. It's really hard to go wrong adding compost, but it's not a one-time fix. You'll need to amend your beds annually, which is why gardeners always say there is never enough compost.

Article Sources
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  1. Making and Using Compost. MU Extension Website