How to Make Your Own Potting Soil? – The DIY Guide

Container gardening is getting popular by the day as very few persons have the time to dedicate to large in-ground gardening. There may be a hefty price tag to pay when you have many pots to fill each season. Switching to a do-it-yourself potting system can cut your gardening budget by half. In this write-up, our gardening experts will show you how to make a potting soil mix for all your plants. 

Potting Soil Mix for plants

Potting Soil Mix

The major thing to understand about a potting soil mix is that it doesn’t contain real soil but rather it’s a soilless blend of ingredients that have been engineered to support plant growth. Potting soil is an ideal growing medium for many types of plants including seedlings, root cuttings, houseplants, or even patio containers and decorative baskets. 

A well-prepared homemade potting soil mix should have a few things in common. These include but not limited to:

  • Better drainage than the average garden soil sample
  • Should be made from lightweight materials that allow easy rooting
  • Ingredient mark-up should be consistent and easy to handle.

Depending on what you need, there are numerous ways to make a potting soil mix.  These mixes can range from textural feel, nutritional content to water retention, and holding capacity.  There are many variants in commercial stores tailored to a specific attribute in line with the needs of customers and extension farmers. 

For optimum results in your potting mix efforts, you need to combine the right ingredients in specific ratios. Here are some pro-tips to the right blend of potting soil for specific plant types.

a potting soil mix

Pro-Tips

  • Seedlings and root cutting do well with lighter and fine-textured potting soil mix
  • Potting soil mixes that have a high percentage of coarse sand and pine bark are best for shrubs and potted trees
  • Decorative cactus and succulent growing plants do well in sandy and gravely textured mixes.
  • An all-purpose mix suitable for growing a wide variety of plants is best suited for perennials, vegetables, and annuals

Potting soil Ingredients for starters

 Many homemade potting soil mixes consist of a rightful blend of some of the ingredients listed below. This isn’t all there is but they are the most popular ones that you can find in commercial stores today.

Peat Moss:  One of the primary and starting materials for many potting mixes is sphagnum meat moss. It is a very stable material to use and does not break down easily. The inexpensive nature of sphagnum makes it a favorite for many extension farmers and DIY enthusiasts.  Sphagnum fills up pot spaces without taking up much weight in the process.

The spores within this material allow for drainage and aeration. However, Sphagnum doesn’t have many nutrients and has an acidic pH. Users can add limestone to the mix to balance out the pH to what is required.

homemade potting soil mixes

Coir Fiber: Coir is a by-product of coconut and bears a high resemblance to sphagnum as a good potting soil blend.  Although, it has more nutrients than sphagnum it is more expensive to buy.  There may be no need to balance the pH as the material is close to neutral.  Many users consider coir fiber as a more sustainable alternative to sphagnum for reasons best known to them.

coir fiber

Perlite: Perlite is more or less like an additional potting soil mix to an already based material like coir or sphagnum.  Perlite is gotten from volcanic rocks and it expands when subjected to heat.  The appeal towards perlite as an additional soil mix material resides in its ability to retain about 3 to 4 times its weight in water. 

additional soil mix materials

Sand: Sand can make part of a potting mix because it improves drainage and adds more weight to the mix. A reasonable amount of coarse sand is needed for the potting mixes targeted at cacti and other succulent plants. 

Vermiculite: Many potting gardeners use vermiculite it to add a bit of porosity to potting soil mixes. Vermiculite is rich in calcium and magnesium and helps the mix increase its water holding capacity.

Vermiculite

Limestone: We have previously talked about the benefit of using limestone as a means of balancing out the pH of Sphagnum meat moss potting mixes. To use limestone, add about a quarter cup of sodium bicarbonate to 6 gallons of peat moss. Limestone is readily available and inexpensive from natural deposits.

Fertilizers: Because potting mixes don’t usually have the required nutrients to support plant growth you need to add fertilizers to provide nutrients. A very good recipe for a potting mix will include a combination of natural fertilizers from animal by-products, manures, or mined minerals.  For best results make use of a combination of several natural fertilizers for your homemade mixes.

natural fertilizers for homemade mixes

Compost wood chips: The benefits of compost wood chips are that they serve to lighten up potting mixes allowing air to travel in and out of the mix.  Many compost wood chips do not break down easily, however, there is a risk that if they do breakdown, they can rob the soil of Nitrogen. In other to prevent this from happening, users are advised to mix with a little bit of blood meal to make up for the Nitrogen loss. Compost wood chips are best suited for shrubs and perennials.

Compost wood chips

Compost: Adding compost material to your potting mix can provide a lot of beneficial microbes and nutrients. The use of compost to a potting soil mix is very important if you need plants to grow healthy. 

Adding compost material to potting mix

Here are a few tips to making your own Homemade Potting soil Mixes

Know that we have gone through all the ingredients that are required to make a potting soil mix, let’s go over some of the steps required to make a mix for specific plant types. We will make do with some of the materials listed above.

Potting soil mix for flowers and vegetables

For flowers and vegetables, we need a blend of natural fertilizers for the healthy growth of decorative flowers and vegetables.  The fertilizer blend will come in handy for other potting mixes as well.  Mix the following natural fertilizers:

Organic Fertilizer Blend

  • Two cups of rock phosphate
  • Half cup of bone meal (for Nitrogen)
  • A quarter cup of kelp meal and
  • 2 cups of greensand

This blend should provide the necessary nutrients from natural fertilizers for growth. Next, for the potting soil, mix the following:

  • About 6-8 gallons of sphagnum peat moss or use the closet alternative coir fiber
  • Add 4.5 to 5 gallons of perlite
  • Mix them up with 6 gallons of compost manure 
  • If you are using peat moss, mix it with a quarter cup of lime to balance the pH
  • Finally, add a half cup of the fertilizer blend prepared above to the container

Potting soil mix for flowers and vegetables

Potting soil mix for trees and shrubs

It’s best to use coarse sand for trees and shrubs in the potting mix in addition to peat moss.  To get started, follow the directions below:

  • Use 3 gallons of coarse sand in the container
  • Mix with 3 gallons of compost
  • Add 3 gallons of peat moss (either sphagnum or coir fiber)
  • Add perlite, 2 gallons should be sufficient 
  • Also, add 3 gallons of composted pine bark to the mix
  • Balance the pH with a little lime
  • Finally, add one cup of the organic fertilizer prepared above. If you are planting acid-loving shrubs and trees you may want to add cottonseed meal to the mix.

For succulents and cactus

The potting mix for succulents and cactus is quite easy to prepare. Follow the instructions below for a well-prepared potting mix:

  • Add 3-4 gallons of sphagnum peat moss or coir fiber. Don’t forget to balance the pH with lime if you are using peat moss.
  • Add one gallon of perlite to the mix
  • Followed by one gallon of vermiculite
  • Finally, add about 2 gallons of coarse sand

For seedlings starters

Follow the potting mix steps below if you are starting with seeds:

  • Use 2 gallons of either peat moss or coir fiber
  • Add two gallons of vermiculite
  • Add one gallon of coarse sand to the mix
  • Finally, if you are using peat moss, add 3 tablespoons of lime to balance the pH.

For houseplants and decorative plants

Household and the decorative plant require special conditions that mimic what is found in natural soil in other to grow healthy. In other to create a potting mix that benefits household plants follow the directions below:

  • Like we did for seedling starters, use 2 gallons of either peat moss or coir fiber
  • Add one and a half gallons of perlite to the mix
  • Two cups of coarse sand 
  • 3 tablespoons of lime to balance the pH
  • And finally, add two tablespoons of the organic fertilizer blend prepared above.
About Jennifer Igra

Growing up in Brooklyn, New York City known for it’s green gardens. Jennifer, a 30 year old gardener and green living fanatic started Igra World to share her gardening journey and increase gardening awareness among masses. Follow Igra World to improve your gardening skills.

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