This Potting Soil Mistake Is Secretly Ruining Your Houseplants

If you care for houseplants for long enough, you'll start to notice they fall into two categories. "[They] need soil that dries out quickly, or soil that holds some moisture while staying airy,” says Adrian Aviles, owner of Athletic Club Flower Shop.

The catch? All-purpose soil doesn't do either, despite its name. It holds onto moisture for too long, leading to root rot and eventual failure. One of the biggest mistakes people make with their soil is simply using the wrong one. Here, we spoke to experts about the repercussions of using incorrect soil and how to choose the best kind for your houseplants.

What Happens If You Use the Incorrect Soil? 

When a plant is grown in the wrong soil, stress usually begins below the surface long before it’s visible to the naked eye.

“Soil that’s too dense, too wet, or poorly aerated interferes with root function, limiting oxygen and disrupting how the plant absorbs water and nutrients,” says Donna Letier, co-founder and CEO of Gardenuity. “As a result, the plant struggles to establish itself, and growth slows or stops.”

These are some common signs that a plant isn’t adjusting well to its soil, according to Letier: 

• Yellowing or pale leaves
• Wilting even though the soil feels wet
• Leaves dropping unexpectedly
• Mushy or darkened roots
• Fungus gnats or a sour soil smell
• Stunted growth or lack of new leaves

“Because these symptoms often resemble underwatering, many people respond by watering more—worsening the problem,” she says. “When soil is properly matched to a plant’s needs, roots settle in quickly, growth resumes, and care becomes far more intuitive.”

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How to Choose the Right Potting Soil

It is relatively simple to choose a potting mix for your houseplants, as long as you keep some basic information in mind.

“Getting the right potting soil is all about balancing a plant's needs when it comes to moisture, aeration, and nutrition,” says Elizabeth Waddington, garden designer and writer at First Tunnels. “Understanding the native habitat, root form, and habit of growth of each plant is a good starting point."

Good soil always drains well, holds air pockets for oxygen, and retains moisture without staying wet. “It shouldn’t compact or feel heavy after watering,” Letier says. “A simple test: If water doesn’t move through the soil within seconds, it’s too dense for most houseplants.” 

Different types of houseplants require different soil:

• Tropical: Look for a soil that balances moisture, airflow, and structure. The soil should contain coco coir or peat moss for moisture retention, pine bark fines or orchid bark to support root health, and perlite or pumice to help improve drainage and prevent compaction.
• Succulents: These plants need soil that drains quickly, dries quickly, and won't retain excess moisture. When reading the ingredient list for succulent soil, look for sand, which will speed up drainage, pumice to keep soil loose and airy, and gravel or crushed stone to prevent compaction and water retention. Succulent soil should feel gritty in your hand and dry out completely within a few days of watering. If it stays damp, it’s too rich.

For indoor houseplants, avoid potting mix that contains fertilizers or moisture-retaining material, sometimes called moisture beads.

“These additives can be helpful for container plantings on your patio under full sun,” says Shane Pliska, CEO of Planterra Interior Landscaping. “But those additives for typical houseplants are unnecessary, and could possibly cause harm.” 

Pliska recommends looking for a bagged, indoor, sterilized, soilless potting mix, with coco coir as the base and perlite or similar materials for aeration and drainage.

“You don't want heavy, compost-rich blends, like soil advertised for growing vegetables,” he says. “When it comes to interior plants, we're maintaining these for ornamental purposes, and want the foliage to look beautiful and lush.” 

Reversing the Effects of Overwatering

“To actually reverse the effects of overwatering, start by pausing all watering and allowing the soil to dry out," says Letier.

To increase evaporation and transpiration, you might move your plant to a warmer, sunnier spot, move it into a breeze, or use a fan to increase airflow. “Make sure no water is collecting below your pots,” Waddington says. “Water should always be able to drain away freely.” 

Repotting a plant that's stressed is usually better than leaving it alone, Waddington continues—in spite of the disturbance.

“Watering less is often not sufficient to solve the issue when the problem relates to the use of the wrong soil,” she says. “You need to address underlying issues of soil structure. Though there are some immediate fixes—such as aerating with a chopstick or another long, thin tool, and letting the soil dry out more between waterings—repotting is the best way to really solve the issue.”

Once roots can breathe, most plants recover quickly and begin showing new growth. To reset the plant’s root environment, Letier recommends:  

1. Gently remove the plant from its pot and shake away excess soil. 
2. Inspect the roots and trim any that are dark, mushy, or damaged with clean scissors or shears. 
3. Repot the plant into fresh, well-draining soil that matches its natural growing conditions. Always use a container with aeration holes. 
4. After repotting, water lightly and allow the soil to dry appropriately before watering again.