Dirt isn’t always the first thing that comes to mind when reviewing a plant’s care needs. Without the right soil, your plants may face otherwise avoidable problems. Soil that’s too heavy and has poor drainage will increase the chances of contracting root rot and other overwatering problems, while soil that’s low in nutrients may prevent your plant from growing. On the other hand, soil with too many nutrients may cause some plants to yellow or become leggy.
Fortunately, finding the perfect potting medium for your plant doesn’t have to be a challenge. Check out our guide here for more information:
Finding the Right Soil for Your Houseplant
When you purchase a houseplant, the plant’s soil needs are usually mentioned in a general care guide included with your plant. However, there are a few general requirements for good houseplant soil. Unless specified otherwise, your soil will need higher drainage levels, room for root growth, plenty of nutrients, and room for air to enter the soil and let the roots breathe.
Types of Soil for Houseplants
Some houseplants may need more drainage or nutrients than others, which is where different potting mediums come in. For example, a garden store may sell potting soils and potting mixes. Potting soil is a mixture that contains soil or sand, compost, minerals, and some organic matter. Potting soil is also rich in texture. Potting mixes do not contain soil or sand and contain organic substances that improve drainage or nutrient levels. Potting mixes are lighter than potting soils and are better for houseplants.
Photo by Kitti Kahotong
Succulent mixes, are great for houseplants like the Snake Plant, String of Hearts, or Hoya varieties. These mixes prioritize drainage above all else and tend to be nutrient-poor compared to other soils. When shopping for succulent mixes, look for packaging that describes the mix as a “cactus” or “succulent” mix. Otherwise, you can modify a potting mix or make your own using organic substances like peat, coir, and bark alongside inorganic substances like coarse sand and perlite to create a light and well-draining mix.
All soils and potting mixes contain at least 50% of an organic substance and 50% of an inorganic substance.
Making Your Soil
To make your own soil, you’ll need a mixture of organic and inorganic substances. Common organic substances like peat and compost are excellent for a homemade potting mix, and they’ll most likely be the base of your mix. Other organic materials include coir, wood ash, and bark. Your inorganic substance is what provides drainage. For this part of the mixture, many gardeners use gravel, perlite, or coarse sand, but you can also use pumice, chicken grit, and even small amounts of clay, depending on your soil’s drainage needs. A soil mix will vary in texture based on your plant’s drainage needs.
To prioritize drainage, look for porous substances like peat, coir, coarse sand, and perlite. For richer mixes that need more nutrients, add compost to your mix.
Measuring Acidity and Nutrient Levels
While most soil packages have general information regarding nutrients and pH levels listed on the packaging, homemade soils tend to vary. Some houseplants, like the English Ivy, Peperomias, and Philodendrons, prefer more acidic soil. Others, like Begonias, Aloe Vera, and ferns like alkaline soil, so it’s important to know your soil’s pH levels. To measure soil pH, you’ll need a soil test kit, which you can buy at a local garden or hardware store. Alternatively, take your soil to a local county extension office, where scientists will test your soil for you.
To measure soil pH, you’ll need a soil test kit, which you can buy at a local garden or hardware store.
Photo via smartgardenguide.com
With your test kit, take a small sample of your soil somewhat away from the plant’s roots (if you’re testing in a pot), and then send the samples to the tester by mail. Soil tests will tell you your soil’s pH levels. When your houseplant’s soil has its preferred pH levels, it’s getting all the right nutrients it needs to grow– that’s why it’s important to test for pH frequently.
Another way to test for soil pH is through vinegar and baking soda tests. For these, take two samples of your soil. In one sample, add a little vinegar over the top of your soil. If it fizzes, your soil is alkaline. In the other sample, dampen your soil with some water, and sprinkle baking soda over it. If it fizzes, your soil is acidic. If both samples don’t react, then your soil is neutral.
Photo by Eskay Lim
How do you change your soil acidity? To make your soil more acidic, consider adding a little compost or sulfur to your soil. Try adding garden lime or wood ash to your mix to make your soil more alkaline. If you want to add specific nutrients like potassium, magnesium, or nitrogen, use a nutrient-specific fertilizer in your soil during the growing season.
How Often Should I Replace my Soil?
You should change your plant’s soil every time you repot it while occasionally fertilizing the soil during the growing season. Repotting times and frequencies usually vary depending on the type of plant you have and how it grows, so pay attention to your plant’s specific needs and growing cycle to know when you should repot. For example, most succulents need repotting once every two years, while Philodendrons need a new pot once every three years. Pothos, on the other hand, require repotting once every year or so. When repotting, always do so during the growing season so your plants can recover from transplant shock and adjust to their new home. When you repot your houseplant, fill the new pot with fresh soil.
You should change your plant’s soil every time you repot it while occasionally fertilizing the soil during the growing season.
Photo by Johner Images
Watch the video below to learn more about perfect soil for houseplants
