Latest posts by Ashley (see all)

DIY potting soil is a hot topic on the internet with some people even profiting off the recipe. Below is an excel document that helps you design your potting soil based on the type of plant, watering styles, and even pot size. This chart will work perfectly for anyone who is looking for a basic rundown of the combos of soil amendments.

Soil Scientist Designed

My name is Ashley and I am a soil scientist with a love for plants. I have been gardening and keeping plants for over ten years. Between my formal education and my love for plants, I have come up with a solution for plant people. The key to any soil recipe is your personality type, overwatering & underwatering. The other keys to look at are soil breathability and also having light or no light source. If you have a breathable pot with good lighting, combined with an underwatering personality style you will want to have a heavier soil. The opposite to this would be having a plastic pot, no light supplement and a heavy watering personality. If this is you your going to want to get an airy light mixture with plenty of wood chips, pumice and maybe even LECA.

If you are looking to reuse potting soil read this article instead.

Remember, you know your growing environment best. What I mean by this is that there is no one fits all potting soil recipe. If there are any plants on this list you want to be included please let me know. This is an evolving document so I will be adding to it over time.

For a how-to video on how to use this guide click the video below.

DIY Potting Soil Recipe Designed By A Soil Scientist

Best Soil For Indoor Plants The Is Pest Free

If you are looking to make your indoor DIY potting soil as pest-free as possible

You need to investigate ways to decrease the overall populations of pests in your potting soil with balance. Heating or applying chemicals, like hydrogen peroxide, can cause pest populations to flourish even more. Utilize techniques such as insect frass to trigger an immune response in our houseplants. Or using predatory beneficial bugs (you can not see) to eat away at potentially harmful bugs like mealy bugs, thrips, gnats and aphids.

These predatory bugs can include things like nematodes or even beneficial mites. Populations of these beneficial bugs can actually be maintained when the pests are not present through the addition of yeast. I have an entire video outlining how to use kombucha SCOBY as a microbiota food source. Kombucha SCOBY is high in yeasts and therefore can act as a food source.

Amendments For Increasing Houseplant Potting Soil Drainage

If you are looking for potting soil amendments that aid in drainage here is a list of what has been scientifically proven to decrease the water holding capacity of your soil:

  • LECA
  • Pumice – the better the size the more drainage
  • Charcoal
  • Perlite – the better the size the more drainage
  • Fluval Stratum
  • Bark
  • Mulch

Amendments For Increasing Moisture Holding Capacity Of Houseplant Potting Soil

If you read my post or watched my video on getting rapid growth in houseplants you likely want heavier soil. To learn more about this look into the role of VPD in plant growth.

If you are looking for ways to help increase the water holding capacity of the potting soil you should try out amendments such as these:

  • Peat
  • Sphagnum moss
  • Vermiculite
  • Topdressing – rocks, pebbles, sand
  • Compost
  • Vermicast

Using Organic Fertilizers Or Amendments In Potting Soil

If you are interested in using organic amendments in your DIY potting soil set up consider microbes. This is important because your plant’s food source needs to be fully cycled. Without microbes, this can happen. If you use vermicast or compost then you need non-sterile potting soil for your indoor plants. To achieve this you will want to use a lactobacillus watering system.

Gardening In Canada