What is Root Rot?

Root rot is an opportunistic infestation of mold spores that occurs when roots are waterlogged and unoxygenated. The roots begin to decay and with the high-moisture content, it creates the perfect environment for fungal spores to germinate and do serious harm to your houseplant. With prolonged water saturation, root decay may occur even in the direct absence of mold and fungal spores. There are countless types of root rot that may get a foothold first or be uniquely suited to that plant root and soil environment. Some of the most common types of fungus and pathogens that can take advantage of root rot include phytophthora, pythium, rhizoctonia, and fusarium.

What to Do about Root Rot

Now that you know what root rot is, the question becomes what to do about it. In most cases, this problem is only noticed when advanced enough to show symptoms above the soil line. This might include discolored or wilted leaves, stunted growth, or an odd smell coming from the plant. There are also common symptoms for root rot in different types of plants. Usually, there’s not much you can do except expose and cut out the affected portion of the plant. This could include some part of the root, stem, or plant foliage. Moving forward, it’s essential to figure out the best way to reduce soil moisture while maintaining a reasonable watering schedule for that plant. If the houseplant was accidentally watered multiple times by different people, this might require little action beyond setting a houseplant care schedule.

What is the Treatment for Root Rot?

There are chemical fungicides that can target and neutralize specific or general root rot infestations. However, these treatments are NOT recommended because they are expensive and not widely available in home and gardening stores. Plus, while the plant may recover more quickly with this type of treatment, extensive root damage still won’t be able to suddenly repair itself. Still, if you have a home full of cherished houseplants, having an antifungal treatment on hand may help you quickly treat and save more of the houseplant.

Prevention and Houseplant Care

Prevention is the best way to fight root rot because root damage is often irreparable and because following a few easy steps should be sufficient to prevent rot in most every case. Really, it boils down to recognizing and following a few of the basic principles of houseplant care:

  • Make sure your houseplants are in pots with good drainage.
  • Especially for succulents, make sure the soil is fast-draining with lots of aerators and soil amendments.
  • Avoid excessive misting or overwatering your houseplants.
  • If you live in a humid climate, you might also think about an air dehumidifier.

If you’re continually struggling with this problem, one of the surest ways to prevent root rot is to water from below and follow other houseplant watering guidelines. More than just using a pot with good drainage, use a catchment pot that will allow you to carefully control the water and moisture level in the root system before emptying the catchment water and letting the soil aerate and dry out.


Do Succulents Need Special Soil?

Yes, succulents need special soil. All houseplants need aerated potting soil, whereas in-ground plants use nutrient-dense topsoil. Drought-resistant succulents, however, benefit from soil that’s even more aerated than regular potting soil. This is done by adding a slightly higher concentration of perlite and sand to the potting mix. The extra aeration helps prevent root rot by allowing the soil to drain and dry out more quickly.

What about houseplants that have already been potted? Do succulents need special soil to survive? Certainly, many succulents can tolerate ordinary potting soil, which already has considerable aeration, but it does complicate the plant care. Specifically, you’ll have less room for error when it comes to overwatering and underwatering. You may be able to repot the succulent in the preferred dry potting mix. Most plants can overcome the short-term stress of being repotted, especially if the new conditions are compatible for the plant.

Now, if the succulent has been doing fine in its current potting soil and watering schedule, you might simply use the special potgting soil for succulents when the time comes to add soil. The opposite is also true. Many tropical houseplants can survive or even thrive in the dry potting mix for succulents by watering just a little more frequently than you would otherwise. That said, it’s hard enough to get the watering schedule just right for healthy houseplants with strong growth. We recommend using special potting soil for succulents when putting a plant in a new pot.

How to Find Special Potting Soil for Succulents

The good news is that it’s easy to find the special soil that succulents need. Major gardening brands offer specially formulated potting soil for succulents and cactuses. There may be other subtle differences as well, but usually these potting mixes simply have more perlite, sand or other aerating agents. You can also make your own special potting soil for succulents. Here is a DIY succulent potting soil mix from Get Busy Gardening, or you can also check out this YouTube video from Fine Gardening.

Use Dry Potting Soil to Help with Overwatering

If you feel like you’re consistently following the water recommendations for your houseplants but still seeing signs of overwatering, it could be a sign that your potting mix is holding too much moisture. People who make the mistake of using topsoil for their houseplants will inevitably struggle with root rot. Putting houseplants in pots without drainage is another common reason to use potting soil with more aeration. Sometimes, root rot can be an issue even with tropical plants that prefer consistently moist soil. The first step is to reduce the frequency and/or amount of water, but another way to help this problem is to add perlite or some succulent potting mix to increase the aeration in your pot.

Other Types of Potting Soil for Indoor Plants

Many types of houseplants will thrive in a standard indoor potting mix that is formulated to provide a viable growing medium for a wide variety of plants. In addition to special soil for succulents and cactuses, there are different types of potting soil and growing mediums for orchids, African violets, and other specialized houseplants. There are also moisture control soil mixes that retain but then slowly release moisture into the soil.


Why is Overwatering Houseplants So Common?

Overwatering is one of the most common problems people experience with their houseplant care. Even many people who are aware of the danger can sometimes end up overwatering their houseplants. Troublesome signs of overwatering include pale, waterlogged leaves; soft, mushy stems; a moldy or rotten smell; yellow or brown discoloration; stunted growth or dropped leaves. If you believe overwatering houseplants is keeping one of your plants from living its best life, consider whether one of these common causes may be the culprit.

  • Overwatering vs. Underwatering Houseplants: Because many of the signs of overwatering houseplants may also describe what happens when underwatering plants, it’s important to look at the entire plant and your recent watering schedule to recognize the difference between the two. You should also recognize that if you’ve been neglecting your houseplants to the point that they are underwatered that you can’t fix the problem by overcompensating and overwatering the plant.
  • Amount vs. Frequency: How often and how much water you give a houseplant is not the same thing. Many people give their houseplants a small amount of water at frequent intervals, when the plant would prefer deep watering spaced out over more time. Misting houseplants is not the same as watering. In extreme cases, it’s even possible to overwater a houseplant and create root rot or mold in the topmost layers of soil, while the bottom of the pot and root system is bone dry.
  • Poor Drainage: Often, signs of overwatering houseplants isn’t about the water at all but is rather a consequence of excessive moisture in the soil. This can happen because the pot doesn’t have drainage holes, the soil doesn’t have enough aerators and fast-draining amendments. If you’re seeing clear signs of overwatering despite only infrequently watering the plant, consider whether the underlying cause is insufficient drainage. Repot the plant and/or amend the soil to improve drainage.
  • Summer Loving: When most people think of their houseplants, they imagine the plant as it looks and acts in spring and summer when bright light and warmer temperatures create the highest watering level needs for the whole year. Many people fail to adjust their watering schedule for the season or else they mistakenly reset their watering schedule after being away from home to this higher watering level.

What to Do for an Overwatered Houseplant

First and foremost, you need to accurately recognize the signs of overwatering houseplants. If there is serious discoloration or damage, that part of the plant is unlikely to recover and should be excised and thrown away. Keep any part of the plant that looks green and healthy. If the damage is minimal and the pot already has good drainage, you may be able to let the soil dry out and then resume a watering schedule tailored for that type of plant. In a more severe case, you should remove and repot the least damaged or discolored part of the plant in fresh potting soil with good drainage.


Can Houseplants Think? Do Plants Have Consciousness?

The scientific consensus is that plants do not have the kind of cognitive faculties necessary to support a consciousness that includes things like self-awareness, theory of mind, or complex emotions. That said, plants do have sophisticated mechanisms for sensing, perceiving, and responding to their environment. Plants do not simply sprout out of the ground, grow toward the sun, and hope for the best. If you watch houseplants for long enough and in a wide range of circumstances, it’s not uncommon to get the impression that maybe plants can think, maybe plants are self-conscious. With this in mind, here are some of the most critical and impressive aspects of plant perception that will help you appreciate the complexity of your houseplants, while also recognizing that houseplants cannot think as we do.

Proprioception: This is the plant’s ability to perceive itself in space. The plant knows if it sends off a growth shoot toward another part of its foliage, the two parts of the plant will connect and can be used for mutual support. The plant will also know where it still has room to grow. Proprioception also plays a crucial role in the plant’s ability to balance itself, while maintaining its other physiological processes. Humans also have proprioception, but this cognitive faculty is distinct from self-consciousness.

Geotropism: Also called gravitropism, this is the plant’s ability to sense gravity. Statoliths within specialized statocyte cells are denser than the surrounding cytoplasm and are sensitive to the force of gravity. But more than just knowing which way is up and which way is down, the plant shows a differentiated response. The plant roots are constantly trying to grow down with gravity, while the stems are constantly trying to grow up against gravity. More than just proprioception and geotropism, some plants can sense orientation and gradients to a degree that they have a fully formed sense of balance, or equilibrioception.

Photomorphogenesis: This is the plant’s ability to detect light and modulate its growth pattern. Again, the plant shows a differentiated response in which the roots are programmed to grow away from light, while the stems and foliage and programmed to grow toward light. This process begins as soon as the seed is germinated. A combination of phytochromes, cryptochromes, and phototropins also allow the plant to detect and respond to various duration, strength, and wavelengths of light. The plant has its own Circadian rhythm, internal clock, and seasonal adaptations. A related process, photoperiodism, detects periods of darkness to regulate when the plant produces its flowers.

Response to Other Stimuli: Space, gravity, and light are some of the most important and obvious ways that plants mimic behavior that can create the impression that plants can think. Even still, these are far from the only stimuli that plants can detect and respond to. Plants can also detect moisture, temperature, sound, touch, physical trauma, pests, and a wide range of chemicals in their environment. They can detect chemicals released by other plants and animals and release their own chemicals to repel unwanted pests and warn other plants that pests are in the area. They can communicate in a kind of common plant language.

Final Thoughts on Plant Consciousness

With these complex sensory and perceptual faculties, it’s no wonder that people wonder whether or not houseplants can think, and whether they might have a consciousness similar to our own. Know that scientists have taken the question quite seriously, but the research and best scientific minds believe plants don’t have consciousness as we think of it. Sure, you can attempt to parse certain aspects of plant perception in ways that parallel human consciousness. In many ways, plants can see, hear, smell, and respond to stimulus, but again the consensus is that the evidence is lacking that plants can learn, feel, or think in complex ways.


Popular Myths about Houseplant Care Practices

If you’re just starting to learn about how to care for houseplants, we recommend you check out our general guide that covers all aspects of houseplant care. If you’re trying to fine-tune your knowledge, learn about some of the misconceptions that may be holding you back. Some myths about houseplant care have taken on a life—and a brand—of their own. (Just adding ice is not the best way to water orchids, for example.) Other myths come from misapplying some basic facts about houseplants or else failing to recognize the ways in which houseplant care can be counterintuitive. 

We have a separate page that discusses myths about potting and placing houseplants. In this space, we wanted to focus on dispelling popular myths about houseplant care practices including light exposure, watering, temperature, and soil quality.

Common Myths about Houseplant Care

  • Water can Focus and Burn Plants in Direct Sunlight: This is just as common with watering the lawn and outdoor plants, but we’ve heard it about houseplants, too. The theory goes that the round water droplets can act as a magnifying glass to focus the sunlight and burn the plant. The theory makes a kind of sense, but it doesn’t represent the facts. Water can act as a magnifying leaves but doesn’t have enough space to focus the sunlight. There is something of this effect on plants with strong hairs that can capture water some distance from the leaf, but even then the science suggests that the cooling effect of evaporating water counteracts much of the added heat.
  • Misting is Good for Houseplants: Arguably, misting houseplants can provide a few, isolated benefits. For one thing, it can serve as a de facto cleaning mechanism for leaves that have gotten dusty, for example. Under direct sunlight in summer, misting can provide a cooling blast and lower the humidity, if only for a few minutes. Misting air plants can help you procrastinate on a full watering soak. That’s about it—even then you need to be careful when misting houseplants. Too much and you can encourage mold and pests to get a foothold. If you want to increase humidity, a pebble water tray or air humidifier is a better method.
  • Using Leaf Shine Products to Clean Plants: The popular home remedies for leaf shine include a mixture of water with milk or mayonnaise. There are also leaf shine products that make all kinds of outlandish claims. Yet, there’s no good evidence to think that leaf shine is any better than water. The important thing is to keep dust and other debris off the plant so the leaves can breathe. This can be done with water and a soft, clean cloth. Most leaf shine won’t hurt the plant directly, but some poorly made or poorly applied products may leave a residue on the leaves which can attract dust and make it even harder for the plant to breathe.
  • Chlorinated Water is Harmful to Plants: This goes hand-in-hand with letting a full jug of water sit overnight to let chlorine and other chemicals settle. There is no evidence that the levels of chlorinated water you’ll find in tap water can harm houseplants. There is more of a debate about whether fluoridated water and fluoride exposure can stunt the growth of plants known to have a higher sensitivity to fluoride, like spider plants. Moreover, forever chemicals and systemic failures to municipal water can lead to unhealthy tap water for plants, pets, and humans. That’s why even though we’re not worried about chlorinated water, we use filtered water for some of our cherished houseplants just in case.  
  • Fertilizer will help weak, stunted growth: Fertilizer provides the final ingredients that houseplants need to take advantage of the extra light and warmth that comes with spring and summer. It is not a health remedy, and it’s not a cure-all for weak growth. Worse, if the plant’s growth has stalled as a natural consequence of the winter season, adding fertilizer could do more harm than good as it sits in and degrades the soil rather than getting sucked up into new plant growth.