Improve your garden soil for healthier plants - Indoor Farmer

Good soil, no matter what you are growing, is the key for healthy plants and great yields.

We have put together a quick guide on how to improve the quality of your soil, so you can maximize your harvest! Some plants may have special requirements that this guide does not cover, as this is intended as a general-purpose advice for the average gardener.

Good soil requires the right mix of minerals, water to air ratio, organic matter and microorganisms. 

Soils that are heavy with clay hold too much water, and are too compact for proper root development. Meanwhile, soils heavy with sand do not hold enough water, and plants can’t absorb nutrients properly. Even with a good mix of sand, clay and silt (loam) you still need organic matter and microorganisms active in the soil to produce healthy, productive plants.

Organic matter is the key to a healthy, productive soil!

Organic matter comes in many forms and has many benefits. It lightens your soil when microorganisms and worms create pathways through the soil. These pathways break up heavy clay soils over time for balanced water and air ratio’s in the soil. Organic matter also has high water retention, and over time will allow sandy soils to hold more water. Organic matter provides nutrition to your plants as bacteria and worms break down its materials so the nutrients can be absorbed by your plants roots. Here are the main types of organic matter for gardeners;

  1. COMPOST – When people ask me how to improve their soil, you would be surprised how many have never used compost! It’s often given away for free from your municipality (although it’s usually mostly leaf compost (leaf mold) which is lower in nutrition. Making your own compost or vermicompost is our preferred method. Lot’s of kitchen scraps like coffee, egg shells, fruit and vegetable scraps and peelings make high quality, highly nutritious compost! Make sure to balance your compost with brown carbon material, unless you are using a bokashi style composter. Finally, you can purchase high quality compost ready to apply to your garden.
  2. MANURE – Aged manure from herbivores provides lots of slowly released nutrition and organic matter. It holds lots of microorganisms and is excellent for water retention. A good source of quality manure is a huge benefit for your garden. We recommend aged or composted manure so it’s not contaminated with potentially bad bacteria.
  3. COVER CROPS – Cover crops are typically planted at the end of the season, their job is to protect the soil from erosion, and replenish the soil with nutrients, while their roots break up compact soil. We recommend a cover crop mix for the most benefit.
  4. PEAT MOSS or COCO COIR – Peat Moss and Coco Coir are amazing for their water retention and as a source of slowly degrading organic matter. Many gardeners incorporate it into the top layer of soil to keep lot’s of moisture available near the surface so seeds and small plants have time to develop. It’s acidic, so use sparingly or with soil amendments to balance the pH. Because it’s acidic, you can use more if you have acid loving plants like Blueberries!

Tips for Improving your Soil:

  1. ADD ORGANIC MATTER - We discussed it extensively because it is your number one resource for improving your soil. This is not to say to use as much as possible, as balance is always key in gardening, but around 30% is of quality organic matter is recommended for a healthy productive soil. It loosens up clay soils, it adds water retention to sandy soils, it feeds microbes and worms for aeration and adds nutrition for plant growth. It’s the key to a healthy garden!
  2. MULCH - Mulch helps retain moisture in your soil, blocks weed development and erosion and adds organic matter as it breaks down. Use a finely chopped wood mulch or straw for your garden beds so its breaks down in time for you to add fresh compost each spring.
  3. MEALS & ROCK DUST EMENDMENTS - Specific amendments can be used to correct for specific problems or deficiencies in your soil. Here is a list of some of the most popular meals, flours or rock dusts and what they are used for;
    1. Dolomitic Lime Raises pH of soil and adds calcium
    2. Kelp Meal / Rocks Dusts and Azomite Adds a large variety of micro minerals to your soil and other benefits
    3. Blood Meal / Alfalfa Meal Adds lots of nitrogen to your soil
    4. Bone Meal Adds Phosphorous and Calcium to your soil
    5. Gypsum – Great for loosening clay soils and adds large amounts of calcium and sulphur
    6. Biochar Improves soil drainage and supports microorganisms in your soil
    7. 4-4-4 or All Purpose Mineral Blends – A great blend of macro and micro nutrients to improve the nutrition of your soil. We highly recommend the premium blends from Black Swallow and Gaia Green.
  4. TEST YOUR SOIL – The only way to know for sure what’s going on in your soil is to have it tested. These tests can be complex for the average gardener to understand, but many nurseries offer this service and can help with diagnosing issues. You can also used raised beds and fabric pots and fill them with a high quality soil made by one of our popular soil brands, and cut out all the guesswork!
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