After my recent post on homemade rooting hormone, you might be wondering about other forms of DIY plant care, like making your own potting soil for your indoor plants. The only problem is, you’ve never so much as attempted homemade potting soil before. What should you use when making your own potting soil? Don’t worry, I’m going to tell you everything you need to know to get you started making potting soil that your houseplants will thrive in.
How to make potting soil for indoor plants? Here are 6 recipes for making your own homemade houseplant potting soil:
- Organic fertilizer + limestone + coarse sand + perlite + peat moss for houseplants
- Vermiculite + pumice + coconut coir for houseplants
- Organic fertilizer + limestone + compost + vermiculite + coir fiber for transplanted seedlings
- Limestone + coarse sand + vermiculite + perlite + peat moss for succulents
- Limestone + perlite + pine bark + coir fiber + coarse sand + compost for shrubs
- Organic fertilizer + limestone + compost + perlite + peat moss for vegetables and flowers
Of course, I’m sure you want to know the exact quantities for the above recipes as well as more about each ingredient. Well, luckily, you’ve come to the right place. In this in-depth guide, I’ll give you the exact quantities as well as tell you everything about making potting soil for indoor plants.
The Benefits of Making Your Own Potting Soil
These days, it’s so easy to DIY just about anything that can be built with your own two hands. YouTube has video tutorials aplenty to ensure success, and there’s something so gratifying about seeing your finished product knowing you made it yourself.
There’s no reason you have to stop your DIY crafting sprees when it comes to your houseplants. Besides the multitude of homemade rooting hormone recipes I showed you last week, or the article I wrote on homemade plant food recipes today, you’ll learn 6 handy indoor plant potting soil recipes too.
Now, as great as DIY is, I know that if you’re a busy person, carving the time out of your tight schedule to get down and dirty with soil and ingredients maybe doesn’t sound like the best way to spend an afternoon or evening. I totally get that, but hopefully the following list of benefits will convince you to try making potting soil for your houseplants. They’ll certainly thank you!
Yes, it’s far more convenient to head to your local gardening supply store and buy your potting soil there, but when’s the last time you checked how much you’re paying for the stuff? Sure, basic bags of potting soil start at about $5 a pop, but once you get into the specialty organic stuff, the prices can be doubled or tripled.
Any chance to save money is nice, and by making potting soil for your indoor plants at home, that’s exactly what you’ll do. Take that extra cash and use it to buy yourself something nice or even treat your plants to a nice new pot to live in with the money you save!
No Heavy Bags to Lug
Most indoor potting soil mix is sold in quarts, which can make you think the bags don’t quite weigh as much as they really do. Then you try lugging your purchase from the gardening supply store to your car and you break a sweat. By the time you get the bag into your home or apartment, you’re spent. That’s fair, as most potting soil bags are several pounds each.
Going the homemade route lets you control soil quantity so your days of dragging around heavy bags of plant stuff are behind you.
No Mystery Ingredients
Do you know what’s in your commercial potting soil? Like, do you really know? If it’s non-organic store-bought stuff, then more than likely, one of the prime ingredients is a wetting agent. Even big names in plant products like Miracle-Gro use wetting agents.
The purpose of a wetting agent is to add moisture to the potting mix so it takes longer for that moisture to absorb. You most often see wetting agents used for irrigation. According to gardening expert Jerry Coleby-Williams, most wetting agents include ingredients like petroleum distillate or alcohol.
The petroleum distillate most commonly used is polyacrylamide, a chemical polymer. Is that really what you want in your houseplant’s soil? I didn’t think so.
When you make your own potting soil, you’ll know every ingredient that goes in there because you personally added them. You can skip the commercial wetting agents and make your own using agar-agar if you must or just forget about wetting agents altogether. Your choice!
You Get to Choose the Texture of the Soil
Not all potting soil is the same; far from it. The texture you need will change throughout the life of your indoor plants. For instance, if you’re transplanting root cuttings or plant seeds to a pot, then you want potting soil with a light texture and fine grains so the plants have room to grow.
Then, as your plant gets older, depending on the type, you’ll use a different texture of potting soil. Vegetables, perennials, annuals, and tropicals do best with an all-purpose type of mix. If your indoor garden is full of succulents and cacti, they thrive with a potting soil that has a texture like gravel or sand.
If you’re growing shrubs and trees indoors, then pine bark and coarse sand will lend the potting soil the appropriate texture.
Finding commercial potting soil that’s textured the way your plant needs it at its current stage of growth is not always necessarily easy. Now you can save yourself the shopping trip and the time by following a DIY recipe or several.
Which Ingredients Should You Use When Making Your Own Potting Soil?
To make the potting soil your plant needs most, you’ll want to have a slew of ingredients at the ready. I do want to mention that you won’t necessarily use each and every one of these ingredients for every recipe, but they’re still good to know.
I’ve talked about compost several times on this blog before. It’s not necessarily the most pleasant of topics; after all, compost is decomposing organic matter, but compost is very useful nonetheless.
It’s quite an adept natural plant fertilizer, and you can also use compost as an excellent ingredient in your homemade potting soil.
The best part is you can make the compost yourself. I recommend one part of green matter to three parts of brown matter (or even four parts if you prefer).
If you don’t remember the info regarding compost from my article about which houseplants like coffee grounds, brown matter includes ingredients that are rich in carbon and often brown. For instance, you may use hay, chopped straw, or fallen leaves. For green matter, add tea leaves, coffee grounds, vegetable scraps, fruit scraps, and other ingredients that are wet and primarily green.
It can take days for your compost to finish decomposing to the point where it’s ready to go, and yes, composting at home can get pretty smelly. The finished product is awesome though, like I said, and you can use your compost pile for a long time.
If you have seedlings that are just starting to sprout, it may be too early to give them compost, but for every other plant, you should be okay.
Composted Wood Chips
If you can, when making a compost pile at home, toss in a few wood chips as well. These improve the ratio of carbon to nitrogen so your compost is a more efficient houseplant fertilizer.
You don’t want the wood chips to break down entirely as they decompose. When in their solid form, wood chips let air travel easily throughout the potting soil. The size of the soil’s pores also increases, which is to your plant’s benefit.
Do make sure you incorporate either alfalfa meal or blood meal in small quantities if your indoor plant potting soil recipe calls for the inclusion of composted wood chips. Otherwise, too much nitrogen can deplete from the soil.
Natural Plant Fertilizer
If your potting soil has a lot of peat ingredients (more on this shortly), then the inclusion of a natural plant fertilizer is recommended. These fertilizers should not include synthetic chemicals, but rather, manure, plant materials, animal byproducts, and mined minerals.
You can even make your own natural plant fertilizer with bone meal and cottonseed meal if you’re feeling ambitious. Otherwise, store-bought should suffice here, but do double-check that yours doesn’t have any synthetic chemicals.
As a sedimentary rock made of carbonate, limestone also includes mollusk, foraminifera, and coral organisms within it. You can get limestone in pulverized form that’s ideal for houseplants. Used often in homemade potting soils that call for peat, the addition of limestone controls the pH so it’s more neutral. This is one ingredient you’ll have to buy rather than make or find, but it’s worth it.
Most succulents and cacti species will need plant potting soil that has sand in it. The grains should be coarse to enhance the drainage of your homemade mix.
Into Succulents? You might enjoy this article:
The phyllosilicate mineral known as vermiculite is often warmed to extreme temperatures until it becomes smaller particles. When you add vermiculite to your DIY potting soil, you’re ensuring your houseplants will get quantities of magnesium and calcium.
Further, vermiculite allows your potting soil to retain water better, and it also boosts the porousness of the soil.
Although you wouldn’t guess it, perlite is actually a type of glass sourced from volcanos. It’s best utilized for its water content, which is quite generous to say the least, considering perlite can hold at least 4x its own weight in water on average.
Besides contributing moisture to your potting soil, perlite also allows for adequate water drainage to prevent root rot, and it boosts the porosity of the soil as well.
Coir is simply a fiber that comes from coconuts, specifically their outer husks. Besides its usage in indoor plant potting soil, coir fiber also appears in mattresses, brushes, and floor mats. You can imagine then that this fiber has a rather rough texture.
You can use coir fiber as a replacement for peat moss in any of the recipes I’m going to share a little later. Coir fiber outlives peat moss, plus it carries more nutrients, so it’s a good ingredient to have.
If you can’t get your hands on coir fiber, then peat moss is acceptable. Also referred to as sphagnum, peat moss adds weight to your potting mix if it needs some thickening. This moss will also retain water yet won’t prevent aeration or draining of the potting soil.
Some downsides of peat moss is that it’s more acidic than neutral. It also lacks nutrients compared to the other ingredients I’ve discussed. Peat moss is also good for only a year or so, so you shouldn’t make your potting soil and then forget about it for a while. It may no longer be good by that time.
How to Make Potting Soil for Indoor Plants: 6 Quick and Easy Recipes to Follow
If you’re ready to get to work making your own potting mix, then let’s get started. Ahead, I’m sharing 6 DIY potting soil recipes for indoor plants that suit all sorts of species and plant life stages.
Houseplant Potting Soil Recipe 1
This first recipe is suitable for mature houseplant species outside of trees, cacti, shrubs, and succulents. Here’s what you’ll need:
|Organic granular fertilizer||(2 tablespoons)|
|Limestone||(3 tablespoons, include only if you’re adding peat moss to this recipe)|
|Coarse sand||(2 cups)|
|Coir fiber or peat moss||(2 gallons)|
Take your ingredients and mix them together. You should get a relatively firm, packed texture to your potting soil. This is one recipe where you don’t want to sit on the finished product too long, so use it as soon as you can.
Houseplant Potting Soil Recipe 2
If you don’t quite have all the above ingredients for the first houseplant potting soil recipe, then there’s another one that trims back on ingredients except all the most essential ones. You’ll need this:
|Vermiculite||(1/4 to 1/2 part)|
|Pumice or perlite||(1 part)|
|Coir fiber or peat moss||(2 parts)|
Make sure the coir fiber or peat moss is premoistened before you begin working with it. It’s also recommended you include limestone with your potting soil recipe if you’re adding peat moss, just like in the recipe before. This neutralizes the acidity of the peat moss somewhat.
Plant Cuttings Potting Soil Recipe
You’re probably collecting a lot more plant cuttings since reading my article about making DIY plant rooting hormone. If so, you can set up your plant cuttings for successful growth by making them this potting soil. Here are the ingredients you’ll need:
Potting soil recipe for plant cuttings to easily take root
|Organic granular fertilizer||(2 tablespoons)|
|Limestone||(3 tablespoons and only if you add peat moss to your recipe)|
|Screened compost (1 gallon)||(1 gallon)|
|Coir fiber or peat moss||(2 gallons)|
Seedling Potting Soil Recipe
Those tiny seeds you planted have germinated and are now becoming seedlings. This is definitely an exciting time. It may also call for a potting soil change so your plants can continue growing to their full potential.
Here’s homemade potting soil recipe just for houseplant seedlings:
|Limestone||(3 tablespoons and only if you have peat moss in the mix)|
|Coarse sand||(1 gallon)|
|Coir fiber or peat moss||(2 gallons)|
Cacti and Succulent Potting Soil Recipe
Are you more of a succulent person? Perhaps your indoor garden is filled with various species of cacti. Either way, like I’ve discussed, these houseplants need a coarser, sand-like type of potting soil that drains well to live happily and thrive.
Ingredients to make your own cacti & succulent potting soil at home:
|Limestone||(2 tablespoons when including peat moss)|
|Coarse sand||(2 gallons)|
|Coir fiber or peat moss||(3 gallons)|
Shrub and Tree Potting Soil Recipe
Many houseplant species would fit the categorization of indoor trees, among them citrus trees, the ficus, yucca, fiddle-leaf fig, and the rubber tree. Some examples of shrub houseplants are the weeping fig and jade plant.
Give your indoor trees and shrubs this potting soil:
|Organic cottonseed meal||(1/4 cup and only for acidic plant species)|
|Organic granular fertilizer||(1 cup)|
|Limestone||(2 tablespoons and only if you have peat moss in the recipe)|
|Composted pine bark||(2.5 gallons)|
|Coir fiber or peat moss||(3 gallons)|
|Coarse sand||(2.5 gallons)|
Vegetables, Tropicals, and Flowers Potting Soil Recipe
- Container fertilizer (1 ½ cup; see recipe below)
- Kelp meal (1/4 cup)
- Bone meal (1/2 cup)
- Greensand (2 cups)
- Rock phosphate (2 cups)
- Limestone (1/4 cup and only when peat moss is included)
- Compost (6 gallons)
- Perlite (4.5 gallons)
- Coir fiber or peat moss (6 gallons)
How Much Homemade Potting Soil Does Your Houseplant Need?
Okay, so following the recipe quantities above, you made one or several of these different plant potting soils. The question is, how much of the DIY soil should you use? That depends on the container your houseplant calls home. Here’s an overview.
Window Box Houseplants
If your plant grows in a window box so it can sit on a sill and absorb sunlight, then its home is wider than it is long.
A 24-inch by 6-inch window box needs 12 quarts of potting soil. If the box is even bigger, such as 36 inches by 6 inches, then add 20 quarts of your DIY potting soil.
Hanging Basket Houseplants
A hanging basket is the perfect dwelling for ivies, vines, and figs, as their long, dangling vines will drape in beautiful, dramatic fashion. For a 12-inch hanging basket, add 6 quarts of potting soil, and for a 16-inch basket, 10 quarts.
Pot or Container Houseplants
What if your indoor plant has a more traditional home such as a pot or container? Here’s how much potting soil you’ll need depending on the pot size:
|Container Size||Amount of Potting Soil|
|8-inch pot||3 quarts of potting soil|
|10-inch pot||6 quarts of potting soil|
|12-inch pot||8 quarts of potting soil|
|14-inch pot||12 quarts of potting soil|
|16-inch pot||20 quarts of potting soil|
|20-inch pot||24 quarts of potting soil|
|24-inch pot||28 quarts of potting soil|
|30-inch pot||72 quarts of potting soil|
|36-inch pot||96 quarts of potting soil|
Storing and Preserving Your Homemade Potting Soil
You finished adding some DIY potting soil to your indoor plant’s container or pot, but you have a lot of soil leftover and nothing to do with it. Where should you put the soil until you may need it again?
An airtight container is the best way to retain the quality of your potting soil. Such a container can include a Tupperware or even a bigger storage bucket if it has a tightly-sealed lid. Even plastic zipper bags might suffice, but make sure they can hold the weight of your soil.
No matter which container you choose to keep the excess potting soil in, I recommend you label the contents, including all the ingredients you used. Potting soils can look deceptively similar, and if you have several soils, you can get confused.
Giving your houseplant the wrong type of potting soil can indeed be detrimental, especially if the soil is more acidic thanks to peat moss but your plant needs alkaline conditions.
Speaking of peat moss, remember that peat moss can die after a year or two, so if it’s in your homemade potting soil, you don’t want to hold onto it longer than that.
Stashing the indoor plant potting soil in your shed, basement, or garage should suffice. However, you don’t want the soil sitting in the sun, as that could speed up the decomposition of some ingredients.
Avoid very cold temperatures as well. If you’re keeping your soil in a garage or basement, I would not suggest putting the soil right on the cold floor.
Making potting soil for your houseplants is advantageous because you can save money and know for sure just which ingredients go into your plant’s soil. Whether your houseplant is in its plant cutting stage, it’s just a seedling, or it’s fully matured, there’s a homemade potting soil recipe for you to follow.
I hope you found these recipes interesting and that you’re as excited to try them as I am to share them with you!