How to Improve Your Soil with Organic Soil Materials and Fertilizer

Krista Bennett

It’s time to get the garden ready and healthy soil is key.

It’s about that time of year and while the plants are growing in the greenhouse, getting bigger and stronger every day, now is the time to think about the next step.

To get your garden or container soil ready for planting them.

If you’re new to gardening, one thing you must keep in mind is that it is hard to be successful at it if you don’t have good soil to work with.

Soil is the foundation of our plants, the same way a foundation supports your home. If the foundation is weak then the structure is weak as well.

Soil is alive with microorganisms that need to be fed with organic amendments regularly. The same way your body uses food as fuel, the organisms in soil use the organic matter in the soil as their food.

Microorganisms provide your plants with nutrients and help defend against pests and diseases. If the soil is dead then it will be a lot harder for your plants to survive.

Following are some ways you can improve your soil organically for healthy happy plants.

First, let’s talk about what not to do.

Chemical Fertilizers

Steer clear of chemical fertilizers. Chemical fertilizers and amendments only mask soil problems and can kill off the microorganisms in the soil.

“Chemical fertilizers negatively impact the soil food web by killing off entire portions of it. Once the bacteria, fungi, nematodes and protozoa are gone, other members of the food web disappear as well. Earthworms, lacking food and irritated by the synthetic nitrates in soluble nitrogen fertilizer move out. Since they are major shredders of organic material their absence is a great loss.” ~Veda Scherer, University of California Cooperative Extension Master Gardener of Calaveras County

So the first thing you can do to improve your soil is to stop using chemical fertilizers and pesticides! I know, it sounds counterintuitive. We’ve been conditioned to believe that we have to purchase expensive chemicals to fertilize our plants and get rid of bugs, but it’s just not true.

Not everyone does this, but it is also important to test your soil.

Soil Test

Once you have stopped using chemicals, get a soil test done by your local cooperative extension or purchase a kit and do it yourself. The results will tell you what needs to be added to your soil based on its current levels of nitrogen, phosphorus, potassium, and micronutrients.

Never add amendments to the soil other than humus without knowing for sure what it needs. You could end up wasting time and money and possibly make the condition of your soil worse.

Organic Materials


The magic ingredient that makes soil nutrient-dense and rich is organic Humus or Compost. Some people think Humus is soil, but it’s a form of mature compost. It is organic matter that can’t be broken down any further.

You can purchase a Humus in bags from a nursery or garden center but Humus or compost can easily be made from scratch using yard waste such as grass cuttings and household waste such as coffee grounds, vegetable peels, eggshells, cores, old bread, and newspaper.

I have a composting bin where I throw my compostable materials year-round.

If material is compostable, it’s added to the compost mound and mixed in so that active microorganisms and air are spread throughout the pile.

©Krista Bennett — Picture of the final stage of decomposed organic materials or humus

Note: Do not put your weed clippings back into the compost bin. They don’t break down. They just start to grow again.

Decomposition occurs faster when the compost is mixed often. In addition to plant nutrients, composting allows concentrated growth of beneficial organisms, including bacteria and fungi, as well as ground-dwelling insects and earthworms.

Humus contains everything a plant needs to thrive. Nitrogen and oxygen are present in abundance, along with potassium, magnesium, and other minerals.

Humus contains more than 25 minerals and nutrients that plants need for proper growth.

Mixing Humus into your soil improves water retention in sandy soils and drainage in clay soils. It’s also a natural fertilizer.


You can add organic matter in other ways by using natural mulches such as shredded wood or bark, shredded leaves, pine needles and grass clippings, and even your kitchen scraps.

All mulch or compost will break down over time adding nutrients to the soil.

Worm Castings

Worms are attracted to organic matter and their castings (worm poop) are extremely beneficial to the soil by providing nutrients and disease-resistant properties.

You can purchase worm castings to add to your garden soil or you can make your worm castings. Collect or purchase some earthworms and add newspapers and worm bedding to a container for 3–4 weeks. After a few weeks, add the worm soil to the compost and mix in.

Besides loosening the soil for plant roots, recent studies have shown that earthworms eliminate unwanted pathogens from the soil as well. Bonus!


Adding one cubic foot of clay every 3–4 months into a compost bin will help infuse trace metals and other inorganic compounds to make a rich compost soil to reapply. Clay soil will also naturally regulate the acidity of the humus soil.


Peat can be purchased at your garden center. It is found in low-lying areas, especially in swamps, bogs, and areas that are frequently flooded and drained. Sediments and minerals are picked up by water and then settle into the low area, concentrating highly fertile soil into small spaces. Peat is sometimes called humus but composting is the more accurate way of producing humus, which is generally used more as soil than peat.

NOTE: Humus or Peat cannot support healthy plant life on their own and they should make up only a percentage of your ideal soil.


A perlite is a form of amorphous volcanic glass. It is a lightweight material like Styrofoam. It’s occasionally called expanded pyrite and is often referred to as “volcanic popcorn.”

Perlite offers a lot of benefits to your garden. The most important benefit is drainage. Perlite is a natural filtration system, allowing excess water to easily drain away while retaining a little moisture and catching nutrients that plants need to grow.

This is especially true in raised beds, container gardens, and even pots or hanging planters.

Airflow in the soil is greatly improved in a bed amended with perlite, which is necessary both for your plant’s roots to breathe and for worms, beneficial nematodes, and other good natural garden inhabitants. Because it’s mineral glass and thus harder than the soil around it, it also helps to slow down compaction and keeps your soil fluffy and lightweight.

Applying Organic Material to your soil.

Add humus material or other composted material on top of your garden soil. Spread a wheelbarrow full for every 10 square foot section of the garden. Mix it into the soil well with a potato fork, rake, or shovel.

Soil can be mixed with a tiller, but tillers are too efficient and cause the soil to dry out, leaving it vulnerable to wind and rain erosion. Use the tiller to break up the base soil, then add the layers of organic materials on top.

Although it takes some muscle grease, using a simple shovel or trowel to mix and churn the humus material into the soil is the most effective method.

I add homemade compost-humus to my garden as topsoil over my clay soil and let nature do its work.

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Krista Bennettwriter, photographer, Proprietor of Evergreen Creek Vintage & Gifts, homesteader, boy-mom-coffeeholic with an acute affection for cats.