Creating your own Potting Soil
Whether you’re starting your garden from seed, decorating your home with flowers, or trying to get an indoor container herb garden up and running, you might still be scratching your head wondering, “why is everyone tell me to buy dirt? I’ve got tons of it sitting right outside!” It’s a common frustration and almost kind of comical. It’s akin to dying of thirst while sitting smack in the middle of the big blue sea.
The reason people tell you to buy dirt is because your little seedlings and container gardens require specific growing conditions to thrive. However, bagged soil mixes often have uncertain origins, lax regulations, significant variation in quality from bag to bag, and aren’t well labelled which all leads to confusion and poorly-made purchases on your end. With a little dedication you will no longer have to make a trip to the super-mega-home-N-garden department store and buy your potting soil pre-made. No more guess work, you’ll be doing your home garden right.
The ideal potting soil will:
• Adequately retain moisture
• Provide excellent drainage
• Have a structure which allow for aeration and won’t compress young roots, but will at the same time anchor growing plants into place
• Contain essential nutrients for plant growth
• Be hygienic and not contain any mould, disease, or harmful microbes
• Play host to an assortment of beneficial microbes
The idea soil for potting indoor container gardens will contain 2-3 of the following ingredients:
• Garden topsoil – congratulations! You already have the most important component of potting mix sitting in your backyard. Rich garden topsoil is a staple.
• Compost – hopefully you’ve gotten you’re compost pile going already! Compost provides all the good stuff – nutrient, soil structure, and overall soil and plant health.
• Sand – this simple substance provides a great natural structure, excellent drainage, and root anchoring for potting mix.
• Manure – I mean, you know what this is, right? The purpose is to add nutrients to the soil. Other fertilisers can be used as replacement for manure.
• Coir fibre – this natural, coconut-derived fibre is very posh in the modern organic farming market. It’s safe, organic, and more nutrient-rich than peat moss. This stuff is great, but is relatively expensive.
• Limestone – this is usually applied to balance out the acidity of other potting soil components.
• Peat moss – the purpose of peat moss is to provide soil structure and retain moisture. Finding an organic and environmentally-friendly peat moss can be difficult. Peat moss harvest takes its toll and, in the end, peat most has no natural ecological place in a home garden.
• Perlite – this volcanic rock is used to hold moisture and enhance drainage. It has a neutral pH and is often used to replace sand in a potting mix.
• Vermiculite – this mineral has to be treated before use and is hazardous to human health. It is often used to retain soil moisture and improve drainage, but is not recommendable for home use.
You now know the ingredients – depending on what you choose to mix into the soil you might still have to buy a component or two, but at least you’ll be buying one single ingredient and you’ll know exactly what you’re getting.
For now, I’ll leave you with a basic potting soil mix which can be used for starting seeds, growing container gardens, and repotting house plants. Measure out each “part” as you see fit, whether one part be a shovelful or small scoop. The important thing is that it’s proportional.
My Basic Potting Soil Mix:
4 parts garden topsoil
1 part sand
1 part perlite
3 parts compost, manure, peat moss or coir fibre