How To Prepare Potting Soil For Indoor Plant
The single most important thing for plant life is its ability to receive nutrients and plants receive most of their nutrients from the soil.
As you can imagine, your potting soil is a pretty important part of a healthy, thriving indoor plant. And with so many types of soil to choose from, it can be tricky to know how to make potting soil for indoor plants.
Get it wrong and your plants will wither and drop leaves in the complaint.
To ensure your success when container gardening, you can put together your own soil for indoor plants. High-quality potting soil can be difficult to find, as commercial mixes usually have synthetic chemicals or other unwanted ingredients.
A proper homemade potting soil mix will take into account the individual needs of your indoor plants, as well as prioritize the use of organic and sustainable materials (ie food scraps).
Let’s dig in! (*pun intended*)
How to make potting soil for indoor plants
The best soil mixes will incorporate a wide variety of potting soil ingredients, including perlite, coco coir, peat moss, vermiculite, coarse sand, and compost, which I’ll go over in this post.
What I will tell you right now is that no matter the combination of ingredients, worm castings have been the most impactful in terms of plant health and growth.
Perlite
What it’s good for: Perlite is commonly used to promote drainage and aeration for potted plants.
Plants that love it: Cacti, succulents, and any indoor plants that require well-draining potting soils.
| Pros | Cons |
| Helps prevent root rot by increasing soil aeration. |
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| An important component in succulent potting soil (along with coarse sand). |
Coir fiber
What it’s good for: Coco coir is used to retain moisture and provide a quality base for a homemade potting soil mix.
Plants that love it: Almost any plant will thrive in coco coir with the addition of soil conditioning amendments
| Pros | Cons |
| Coconut coir is a renewable resource, making it a sustainable choice for homemade potting soil. | Depending on your location, coco coir is sometimes difficult to source. |
| Makes an excellent substitute for unsustainable peat moss and sphagnum peat moss products. | Does not contain any nutrients, requiring you to supplement with compost or organic fertilizer. |
| Helps retain moisture in soil for indoor plants. |
Peat moss
What it’s good for: Peat and sphagnum peat moss have excellent water retention properties.
Plants that love it: Many vegetable and fruit plants enjoy the low pH of peat moss.
| Pros | Cons |
| Peat moss and sphagnum moss promote water retention. |
|
| Peat moss and sphagnum moss will decompose slowly, releasing nutrients over a long period of time. |
Vermiculite
What it’s good for: Vermiculite retains water and promotes good soil drainage.
Plants that love it: Any species that appreciates moist soil.
| Pros | Cons |
| Vermiculite holds water for a longer period of time than other media. |
|
| Can be reused in the garden, as it does not decompose. |
Compost, fertilizer, worm castings
What it’s good for: Provides nutrients and organic material, which promotes healthy plant growth.
Plants that love it: All indoor and outdoor plants require soil nutrients from compost, fertilizer, or worm castings to properly grow.
| Pros | Cons |
| Organic fertilizers are a sustainable method for adding nutrients to your homemade potting mix recipe. |
|
| Some sort of organic nutrients are required for healthy plant growth. | |
| Some options, such as composted wood chips, can also help with water retention. |
9 Best Potting Soil Mix Recopies
1. General potting soil recipe for flowers, tropicals , and vegetables
6 gallons sphagnum peat moss or coir fiber
4.5 gallons perlite
6 gallons compost
1/4 cup lime (if using peat moss)
1 & 1/2 cup of the DIY container fertilizer blend found below OR 1 & 1/2 cups of any granular, complete, organic fertilizer.
Now Mix together
2 cups rock phosphate
2 cups greensand
½ cup bone meal
¼ cup kelp meal
2. Potting soil recipe for potted trees and shrubs
3 gallons compost
2.5 gallons coarse sand
3 gallons sphagnum peat moss or coir fiber
2.5 gallons composted pine bark
3 gallons perlite
2 TBSP of lime (if using peat moss)
1 cup granular, organic fertilizer (or 1 cup of the DIY container fertilizer blend found above)
1/4 cup organic cottonseed meal, if growing acid-loving trees and shrubs
3.Potting soil recipe for succulents and cactus
3 gallons sphagnum peat moss or coir fiber
1 gallon perlite
1 gallon vermiculite
2 gallons coarse sand
2 TBSP lime (if using peat moss)
4. Potting soil recipe for seed starting
2 gallons sphagnum peat moss or coir fiber
2 gallons vermiculite
1 gallon coarse sand
3 TBSP lime (if using peat moss)
5.Homemade potting soil for transplanting seedlings
2 gallons sphagnum peat moss or coir fiber
2 gallons vermiculite
1 gallon finely screened compost
3 TBSP lime (if using peat moss)
2 TBSP granular, organic fertilizer (or 2 TBSP of the DIY container fertilizer blend found above)
6.Potting soil recipe for houseplants
2 gallons sphagnum peat moss or coir fiber
1.5 gallons perlite
2 cups coarse sand3 TBSP lime (if using peat moss)
2 TBSP granular, organic fertilizer (or 2 TBSP of the DIY container fertilizer blend found above)
7. Basic Outdoor Container Potting Soil
This all-purpose outdoor container mix is nutrient-rich, and provides good water holding capacity for your summer pots and planters. Get the full instructions for how to make outdoor container soil here.
- 2 parts peat mossor coir(pre-moistened)
- 2 parts compostor composted manure
- 1 part perlite
- 1/4-1/2 parts vermiculite
- 1 tablespoon garden limefor each gallon of peat moss
8.Outdoor Soilless Potting Mix
This soilless potting mix recipe will provide your outdoor hanging plants with everything that they need to grow successfully.
It’s a lightweight and long-lasting media that is perfect for window boxes and hanging baskets.
- 2 parts peat moss (or coir)
- 2 parts vermiculite
- 1/4 part ground limestone
- 1/4 part super phosphate
- 1/2 part blood meal
9. Acidic Potting Soil
This potting soil mix has a high percentage of peat moss, which is naturally acidic.
Use this recipe, without amending it with garden lime, to provide a medium that is perfect for plants that thrive in acidic conditions.
- 4 parts peat moss
- 2 parts compost or composted manure
- 1 part perlite
- 1/4 – 1/2 part vermiculite
How to Improve Your Potting Soil
Take these steps to ensure your plants have the soil they need:
- Repot every year if you are using peat-based bagged potting mix.
- Improve bagged potting mix. It’s not a long-term fix, but you can improve on peat-based potting mixes by adding some organic matter and perlite.
- Flush the soil thoroughly every month, at a minimum. Take the plant to the kitchen sink or outside and thoroughly flush the soil to wash out accumulated salts from fertilizer and deposits from tap water.
- Wick your pots. Insert a wick through the drainage hole in the bottom of the pot. This won’t help with compaction, but it will wick away excess water in the pot and help drainage, thus reducing the chance of root rot.
- Make your own potting mix. Many gardeners mix up their own potting mixes based on composted bark, coconut coir, peat, perlite, vermiculite, pumice, and other soil additives. This is a more advanced option, but it is possible to build a soil that will last for two or more seasons if you make it yourself.
