Acidic vs Alkaline Soil for Houseplants

Not all houseplants like the same kind of soil. Along with moisture control and nutrient content, soil pH is important for keeping your houseplants healthy. Now, a lot of people use the recommended potting mix for that houseplant, never think about the pH, and have a ton of success. Many standard potting soil mixes for houseplants tend to have a pH of about 6.0, just slightly acidic. This is just acidic enough for most acid-loving houseplants and just neutral enough for houseplants that prefer a higher pH.

The Best Soil and Houseplant Care Practices

Most people who cultivate houseplants know about the differences between regular potting soil, fast-draining soil for succulents, and specialized mixes for orchids. To review this type of information, check out our main resource page for choosing the best soil for your houseplants.

You should also know that some houseplants like acidic, neutral, or even slightly alkaline soil. A mild deviation from the ideal pH will rarely kill a houseplant directly. It may result in lackluster growth, or it may be why a houseplant isn’t flowering. It can also make a houseplant more susceptible to pests and disease. Severe deviations can lead to serious disruptions in delivering nutrients or damage to root systems. Especially for long-term houseplant care, it’s important to have a soil meter that can measure pH and help you monitor the acidity or alkalinity of your potting soil.

How to Make Alkaline Potting Soil More Acidic

Depending on where you live, the mineral deposits in hard tap water can gradually turn the soil alkaline. (Water softener can be even worse as the salts that comprise these softeners are also harmful to plant roots.) Composting is another common cause. You can make your own potting mix at home, but composting can create a more alkaline potting mix. A simple solution is to add peat moss which will increase the aeration, drainage, and acidity level of the soil.

Another creative way to gradually increase acidity is to collect and use rainwater for your houseplants. Rainwater tends to be slightly to moderately acidic in most places. Finally, you can look for fertilizers and soil amendments that have been specially formulated for greater acidity.

How to Make Houseplant Potting Soil More Alkaline

It’s more common for tap water to increase alkalinity, but the composition of some tap water may instead leach more of the calcium and magnesium than other nutrients, slowly causing the soil to become overly acidic. Using rainwater with higher acidity levels is another possibility. Overuse of peat moss and other alkaline soil amendments could also be a contributing cause.

One quick way to increase the alkalinity of your potting soil is to add dolomite lime. However, some gardeners suggest looking for other types of rock dust with minerals that are more likely to benefit your houseplant. The benefits of rock dust may depend on how quickly the dust decomposes into nutrients that the houseplant can access. Seaweed is another popular choice to add nutrients and reduce acidity level.

Perlite and vermiculite are two soil amendments with pH 7-7.5 that can help maintain a growing medium with more neutral pH. The perlite is a kind of volcanic rock glass that is a superior aerator for fast-draining potting mixes. Vermiculite is a kind of clay that is also an aerator, but which retains more moisture than perlite.

Houseplants that Like Acidic vs. Alkaline Soil

Some finicky houseplants may need to stay within a narrow range for soil pH, but many popular types of houseplants are fine with slightly acidic soil and have a high tolerance for soil pH in general. Some exotic houseplants may also need unusually acidic or alkaline soil.

Houseplants that are known for liking more acidic potting soil include the azalea, hydrangea, parlor palm, camillia, amaryllis, and most varieties of orchids and cacti. Few houseplants prefer truly alkaline potting soil, but some plant types like neutral to very mildly alkaline potting mixes including the asparagus and maidenhair ferns, hyacinth, oxalis, and canna lily plants. There is no definitive chart for ideal pH soil conditions for every type of houseplant, but here are some of the useful lists we’ve found online.


Does it Matter How Big My Catchment is for Houseplant Drainage Pots?

Putting houseplants in a catchment and drainage pot allows for quick drainage and easy watering of indoor plants. Which is a pretty darn good start for houseplant care. Better yet, knowing how to choose a catchment of the right size is essential for getting the water and soil moisture levels right for different types of houseplants.

Simply having a catchment for overflow water is not a cure-all for overwatering and underwatering. In fact, in some cases, it can lead to bad houseplant watering habits. You may think that the excess water in a catchment means you can drown houseplants and then ignore them for long periods of time. This can lead to undetected root rot from standing water, or it can lead to parched plants if the temperature and home humidity levels causes the water to evaporate and the soil to dry out. For these reasons, it definitely matters how big your catchment is for drainage pots.

Deep Catchment and Drainage Pots

Especially if you want to use a water catchment with a succulent or low-water houseplant, it’s important that the water still drains quickly and completely from the soil. You need a generous amount of space to make sure water and high moisture levels do not reach the potting soil. Another side effect is that these tall catchment pots had height, turning a small- or medium-sized houseplant into a large one.

These types of deep catchments are usually designed for specific drainage pots. That’s because you need something to support and hold the primary pot at the top of the catchment. Certainly, some people build their own deep catchment and pot support. But while the perfect deep drainage catchment may not be easy to find, it’s usually better to stay patient and keep looking rather than take the DIY approach.

Small Drainage Plates and Saucers

These are probably the most common types of catchments for houseplants. Ceramic pots may have their own. Ceramic and other molded pots may have their own saucers as part of their drainage system. Drainage saucers and pots may be sold together as two-piece potting sets. It’s also easy enough to find saucers for teacups that can be added to simple drainage pots.

This is great for medium-water houseplants that don’t mind having the bottom layers of potting soil stay wet for a few hours after watering. They may still be vulnerable to root rot with consistent overwatering. Ideally, you’ll still have access to all sides of the pot. That way you can saturate the potting soil before too much water drains and overwhelms the plate or saucer and runs all over.

Wide and Tight Water Catchments

In many ways, this is the opposite of deep catchments and the types of houseplants that are likely to thrive in these pots. If you have a hygrophyte houseplant that loves lots of water and moist soil, then this type of system may work well. If you have a group of houseplants like this, you can also find or create a catchment tray that will hold the runoff water and help create consistently moist potting soil.

If you happen to like the look of a big, wide water catchment for home decorating, you can still use this setup with medium-water and low-water houseplants. You simply need to be mindful of how much water you give the plant and be prepared to empty the catchment if needed.

Choosing and Using Water Catchment Pots

So, yes. The size and shape of the catchment matters to your houseplant care and best watering practices. Like most things, it’s important to strike a balance to avoid under- or overwatering. But you must also know your houseplants and which ones like higher or lower moisture levels in their potting soil. Let the type of catchment you choose help remind you how to water your different houseplants. You can also make additional notes in a houseplant journal.


How to Tell the Difference between Philodendron and Pothos Plants

Whether at a house party or in an office space, you may be admiring a houseplant that you think you recognize as a philodendron or pothos plant, but you’re not entirely sure which one. Some people even mistakenly believe they are the same plant that goes by two different names. And if the plant was a gift or an afterthought, the owner may not know what type of plant it is, either.

We here at Houseplant Finder know our plants pretty well, but sometimes we can’t always tell the difference between a philodendron and pothos from across the room. That said, upon closer inspection, it’s usually quite easy to spot the differences if you know what to look for in the plant leaves, stems, and stubs.

How to Tell the Difference in the Leaves

Both plants have waxy leaves, but the pothos has more defined venation. The leaf veins of the pothos are easier to see with ridges that can be felt by running your fingers over the leaves. The philodendron has smooth leaves and gently sloping undulations. This is the best way to tell the difference if you have both kinds of plants. Philodendron leaves may not be perfectly smooth, and pothos leaves are still waxy enough to feel relatively smooth. Yet, in a side-by-side comparison, the difference is usually obvious. (Note: There are types of both pothos and philodendron with neon leaves.)

How to Tell the Difference in the Stems

Start by looking at the color. The pothos tends to have a much more uniform color in its stems and leaves, whether it’s a green or neon variety. In contrast, the philodendron stem has a brown or salmon color that is most noticeable at the ends of the vines. You should also look at any new growth. Philodendron leaves initially form in cataphylls, or a protective sheath. Pothos leaves grow directly out of the vine.

How to Tell the Difference in the Stubs

By stubs, we mean the aerial roots which help vine plants latch on to and gain extra support from the things they find in their surroundings—whether it’s a tree or an interior wall. Both types of plants are pseudo-epiphytes: They have main vine stems and fibrous roots in the soil, but they also rely on other plants for physical support. So, while both plants have these aerial roots, they look quite different on each type of plant. The pothos has singular, thick, dark-colored stubs. The philodendron has thin aerial roots that grow in bunches at the bottom of the cataphyll (protective sheath).


What are the Veins on a Leaf Called?

They are just called veins, but collectively, the pattern of veins on a leaf are called its venation. There are two main types: parallel venation and netted venation. This is exactly what it sounds like. When the veins run in the same direction as the leaf itself, that’s called parallel venation. When the veins run perpendicular or throughout the entire leaf in a dynamic pattern, that’s called netted venation. (Netted venation is also known as reticulate venation.)

What do Plant Leaf Veins Do?

They serve a remarkably similar purpose as our own veins. Plant veins deliver water, minerals, and plant energy through the leaf and rest of the plant. Like our muscles and bones, these veins also provide physical support for the leaf to hold it against the wind, water, and elements.

Also, if you’re looking online for information about houseplant venation, it’s a good idea to add the word “plant” as part of your initial search. That’s because it’s also common to talk about the venation of insect wings.

What are the Different Types of Leaf Shapes Called?

There are a handful of major leaf shapes, also known as leaf margins. The different types of leaf shapes are based on just the outline of the leaf, not the venation pattern. The veins of the prayer plant may dissect the leaf, but the shape of the leaf itself is simple and regular.

  • Entire Leaf: This is a simple leaf shape with smooth, regular edges.
  • Toothed Leaf: These leaves have a regular shape overall, but with toothed edges. Many horticulturalists will break this shape into two separate leaf margins. With pointed teeth, it’s called a serrate leaf margin. With rounded teeth, it’s called a crenate leaf margin.
  • Lobed Leaf: These leaves are dissected into distinct sections or lobes. Unlike parted leaves, the indentations go less than halfway through the leaf.
  • Parted Leaf: These leaves are deeply dissected with clefts that run more than halfway into the leaf. Ornate fall foliage is often depicted with a parted leaf shape.

You can learn even more about the various terms and subtypes for leaf margins here. This resource will explain the differences between doubly serrated, ciliate, dentate, undulate leaves, and more.


What can You Do for Houseplants with Root Rot?

Now at the beginning of winter is among the most common times to overwater your houseplant and start to see signs of root rot. We may be spending more time being at home, cleaning the house, and decorating our living spaces. We want to take good care of our houseplants. We want to tend to them and give them water, right? Well, no. Here is what you can do for houseplants with root rot due to overwatering.

Temperatures, humidity levels, and light exposure are all dropping during this time. Most houseplants don’t actually go dormant during the winter. But they do slow their growth rate and nutrient absorption to conserve energy and match the environment during the winter season. The air may feel drier in your home with a forced-air furnace, but the warmer temperatures still mean water evaporates more quickly in the summer.

Does Your Houseplant Have Root Rot?

If you notice signs of yellowing or wilted growth shortly after you start watering a houseplant more frequently, there’s a good chance it’s a sign of root rot. Mild yellowing, browning, or wilted growth may have to do with slight imbalances in pH or insufficient nutrients. This could have to do with soil composition or too much or too little light exposure. Nevertheless, overwatering and root rot are among the most common problems with houseplants, especially during this time of year. Learn more about what root rot is exactly.

Treatment of Root Rot in Houseplants

The final step in identifying root rot is also the first step in helping your houseplant recover from rot. You need to remove the houseplant from the soil and wash as much of the soil off the roots as possible. You want just the roots, stems and foliage. You want to visualize as much of the roots as possible. What you’re looking for is color and consistency. Healthy roots for most every type of houseplant will be white and firm to the touch. Roots with rot will be brown and a little mushy. Like it’s decomposing. Look at the periphery of the root structure. The tips of the roots are where most rot problems start.

Once fungal spores have started to multiply and get a foothold, there’s little that can be done to save the affected part of the root. What can be done is to remove any and all significant fungal growth. After you’ve washed the roots completely clean, use sharp scissors or small pruning shears to cut off the damaged part of the root. Save as much of the healthy root as you can, but be sure to remove any part of the root that seems soft or brown. This is why it’s so important to treat root rot as soon as you suspect a problem. If the foliage above the affected root is yellow or damaged, remove it as well if you haven’t already.

Next, spray the roots down with a fungicide to make sure any remaining spores can’t start multiplying again. Put the houseplants aside in a safe place. You will need to throw away the old potting soil. Sanitize the pot with a diluted solution of bleach (1%), hydrogen peroxide (3%) or vinegar (5%), and then rinse with water. Use fresh potting mix to repot the plant.

Road to Recovery from Root Rot

You can apply some root growth stimulant when first repotting, but you don’t want to use fertilizer while the roots are regrowing. Fertilizer helps established roots deliver even more nutrients to the plant’s foliage and flowers, but it doesn’t help the roots themselves.

The most important thing to help your houseplant recover from root rot is avoid overwatering the houseplant without neglecting it altogether. Make sure you know whether that type of houseplant truly thrives on neglect or whether you just got overzealous. Be patient. The plant may not recover overnight or even after the first week, but if you follow these steps and you still have a decent amount of healthy roots to work with, your houseplant should rebound in a major way before too long.


What You Need to Know about Bottom Watering Houseplants

Bottom watering houseplants is popular among some people, but if you don’t know why and how to water plants from the bottom, you could end up hurting the plant. The harm can happen primarily in one of two ways. Either the water doesn’t reach the top of the soil leaving it perpetually dried out, or the water sits in the bottom of the pot for too long causing root rot infiltrate the root extremities and spread up from there. At the same time, there can be solid reasons for choosing this strategy, at least some of time, for watering houseplants.

Why People Choose to Bottom Water Houseplants

  • Cold Water Spots: Some houseplants are susceptible to permanent cell damage from the thermal shock of cold water landing on their leaves. The tiny white scars that form are mostly harmless. One solution to avoid cold water spots is to water that is close to room temperature, but bottom watering also helps guard against this problem. Similarly, the minerals in hard tap water can leave a powdery mildew. Use filtered or purified water. If you bottom water with tap water, it’s a good idea to periodically measure the soil pH and amend the potting mix as needed for that houseplant.
  • Wet Feet and Rotting Crowns: Have you heard there are some houseplants that don’t like wet leaves? First, it’s important to know that these plants are, in fact, fine with their leaves getting wet. It’s the divots at the bottom of the leaves, known as the crown, that can suffer from rot when water collects in these areas for too long. If you notice a lot of water has fallen into these crowns during top watering, it’s not a bad idea to take a paper towel and soak some of it up. But another way to get around this problem is to bottom water these plants most of the time.
  • Convenience and Access: Even a houseplant with foliage that doesn’t mind getting wet can be difficult to water from the top, if the foliage and stems are crowding out access to the potting soil. Watering from the top may lead to runoff and make a small mess. Access may also be an issue with a tall wall shelf, where you can barely reach the plant to begin with. Why not just put the houseplant in a catchment pot and put a bunch of water in there for the roots to soak up? This is certainly an option, but to do it right, it may not be as convenient as you think. It’s simply too hard to get the water levels right where the plant can soak up enough water without exposing the bottoms of the root to rot.
  • Fungus Gnats and Moisture-Loving Pests: For some environments and for some plants, it may be beneficial to keep the top level of potting soil. To be clear, most houseplants pests thrive in lower humidity levels, but there are a few exceptions, and fungus gnats are by far the most common of these. Thus, if you live in a more humid climate and you’ve had trouble with fungus gnats in the past, you could try to moving to a mostly bottom watering technique as part of your gnat control and prevention measures.

Tips for Bottom Watering Houseplants

  • Rather than throw a bunch of water in a catchment pot indefinitely, use a removable catchment. You can then soak the houseplant in water for about 10-20 minutes, depending on the type and size of the plant, before removing the catchment and letting the roots breathe.
  • Get a fancy self-watering pot. We recommend the kind with separate reservoirs, overflow holes, and a wick to draw the water up to the top of the plant. Basic self-watering pots may also work, but you continue to run the risk of root rot.
  • When generally watering houseplants from the bottom, you might get out a water bottle and mist the top of your plants and soil. This will keep the top of the soil from drying out completely with minimal risk of rot.

Find Out What Types of Houseplants Don’t Like Wet Leaves

Strange as it sounds, some houseplants don’t like wet leaves. Technically, their leaves are fine, but when the water pools in the “crown” at the bottom of their leaves, you can have problems. This is sometimes called plants with “wet feet.” Left in this state for too long, rot can take hold and slowly destroy that part of the plant. Larger areas of rot may also choke off nutrients and cause the foliage to die back.

How is this possible? Don’t plants get rained in the wild? Even tropical forest plants that like humid conditions in general can have leaves that don’t like being wet. The answer is a combination of factors. Water evaporates more quickly outside, and there’s a lot more airflow which also helps. Thus, rarely do you see large-scale problems with this type of water damage, but there’s nothing that says plants in the wild are immune from rot.

The other big problem with wet leaves occurs when using cold water. The thermal shock of cold water can disrupt photosynthetic activity and permanently damage the structure of palisade leaf cells. The result is white spots on the leaves that are harmless but close to permanent, like scars. Unless you are especially careless and use especially cold water, these spots won’t threaten the overall health of the plant.

Types of Houseplants that Don’t Like Wet Leaves

This isn’t an exhaustive list, but it does include the most popular houseplants that fit this profile. Moreover, some are more vulnerable to this type of water damage than others.

African Violets: These houseplants are particularly difficult to care for, but they do have a few eccentricities including not liking wet feet. More than just watering technique, it’s important to look at the foliage of your African violet. Individual plants may have especially tight crowns that need to be watched. This is also a plant that’s susceptible to cold water spots.

Orchids: Orchids are known for having large, broad leaves that are sensitive to both direct light and standing water. In nature, some types of orchids grow upside down reducing the likelihood that water gets trapped in the crown. At home, be mindful of water that runs down into the bottom of the leaves. Some people also use ice cubes to slowly release water but also to decrease the temperature during the winter to help stimulate new shoots and flowers.

Snake Plants: This houseplant is among the most susceptible to root rot from wet feet. Even misting can lead to enough moisture for rot to take hold. The good news is that snake plants don’t need water all that often, and they are otherwise among the most versatile plants with high tolerances for light exposure, humidity levels, and temperature.

Cape Primrose/Streps: This houseplant isn’t immune to root rot and wet feet, but it’s especially vulnerable to cold water spots and mineral stains. The cape primrose has broad leaves and a sprawling pattern that make a long-nosed watering can important for reaching the potting soil and keeping the leaves dry.

Pygmy Date Palm: Some houseplants are vulnerable to specific kinds of rot and fungal growth. The pygmy date palm is a good example. The pestalotiopsis fungus has a particular liking for these palms. They get a foothold with the leaves are wet, but can often beyond a chronic problem that houseplant owners have to continually treat with root rot.

Watering Tips for These Houseplants

One of the surest ways to make sure that leaves stay dry is by bottom watering the houseplant. Another basic, but effective, tool is the long-nosed watering can. Just because the potting soil is hard to see or get to and just because there’s some danger to the leaves, it’s still important for every part of the soil to receive enough water to release its nutrients.


Why Now is the Best Time of Year for a New Houseplant

Spring is the best time of year for a new houseplant or repotting an existing one. The ample amounts of light provide extra energy that the houseplant can use to get established, whether it’s acclimating to a new pot or acclimating to a new spot. Giving houseplants the length of the growing season sets them up for the best chances of success. It’s also a great way to acknowledge the start of the spring season. It doesn’t have to be the official start at the equinox, either. Take care of your spring houseplant care, new plants, and repotting at the end of February or beginning of March. That way, you can get things a little dirty and then you can tackle your spring cleaning head-on.

Best Time of Year to Start a Houseplant from a Cutting

One exception to this rule is starting a houseplant from a cutting that will grow new roots. In this case, it may be better to wait till late spring or early summer in which the plant foliage is likely to be strongest. The cutting and new plant will still have the rest of the growing season to establish its roots and prepare for next winter, but weaker cutting may never get established at all. This is the big reason why it’s usually recommended to take at least 2-3 cuttings in anticipation that they may not all make it.

More Times of Year to Start a Houseplant

There is no wrong time of year. If you have a good spot and proper plant care, most plants will find their footing and start to thrive before too long. If you’re repotting or just bringing a houseplant home to a new spot, it’s not uncommon for plant foliage to show signs of distress. Often, this is just a sign that the houseplant is working to establish new roots, rather than grow new leaves. Before long, the foliage will bounce back and, in the right conditions, eclipse its former glory.

You can try to cheat a little by putting the houseplant in a sunnier window spot during the winter before moving it to more partial shade in the spring. (Of course, if the houseplant likes lots of strong light, it should have a sunnier spot on a permanent basis.) There are a couple different philosophies here. Many plants are well-suited to the seasonal changes of natural light that happen at moderate and higher latitudes. Now, if it’s a tropical plant in its natural habitat, these houseplants may be better adapted to more consistent amounts of light throughout the year. (Note, however, that many tropical plants are adapted to living in the shade of trees and don’t necessary like lots of direct sunlight.)

The type of houseplant matters for more than just modifying the light exposure. It’s easy to find sources that offer plants that can be grown indoors in the fall, but it’s also revealing that these houseplant lists are dominated by resilient, easy-care houseplants.

Best Time to Start Outdoor Plants

There is no wrong time to start a plant, and this is true of many outdoor plants as well. So long as the ground isn’t in a hard freeze—or we sometimes say until the first snow falls—you can put new plants in the ground. Certainly, in climates with hot dry summers, there’s an additional watering burden for getting outdoor plants established. When growing from seed, it’s often best to plant at the end of the growing season and wait till next year.


Why and How to Clean Houseplants: Tips, Benefits & Types of Plants

Healthy houseplants are clean houseplants, or are they? Do you need to clean houseplants, and if so, how do you do it? The short answer is that it’s a good idea when done right but isn’t the most important part of houseplant care. Here is what else you should know about how to clean houseplants.

Is It Important to Clean Houseplants?

If you want houseplants that are as healthy and vibrant as possible, then a little light cleaning is a good idea. When a lot of dust builds up on leaves, the plants won’t be able to get the same amount of light and air that it needs for photosynthesis. Often, it boils down to houseplants that survive vs. houseplants that thrive. You can have houseplants for years and never bother to dust or clean their leaves, but if you want these plants to live their best lives with full foliage and flower growth, then yes it’s important to clean. The other reason why you should clean houseplants is that it provides an opportunity to closely inspect your houseplants for signs of pests or disease. Keep an eye out for weak growth, unusual spots, or discoloration.

How to Clean Your Houseplants

First, remove any dead, fallen growth from the soil and area surrounding the pot. Next, remove any diseased, discolored, or dead growth that’s still attached to the plant. Should this be necessary, it’s best to use clean, sharp scissors or pruning shears to help the plant repair itself and prepare for new growth.

Next, take a clean cloth and gently clean the remaining leaves. A light misting can facilitate this process, but we recommend wiping the leaves with a cloth afterward. Support the leaves with your hand to avoid damage during this process. For houseplants with leaves that don’t like to get wet, like the African violet, you can use a soft-bristle paintbrush or a plain toothbrush if you’re careful. Find more plant cleaning tips.

How NOT to Clean Your Houseplants

There are just a couple things you need to watch out for. You shouldn’t need to scrub or otherwise become abrasive when cleaning houseplant leaves. Simply get the dust or mildew off the leaf. Leaf shine is NOT the way to clean your houseplants. These oils, waxes, and polishes will make your leaves look glossy for a little while, but will clog pores in the leaves and reduce plant respiration. A healthy houseplant will be fine, but if anything, this type of leaf shine treatment is adding stress to your plant.

If you like the look of glossy foliage, we recommend a ZZ plant, schleffera, jade plant, peperomias, or other plants with waxy leaves. The only times we recommend using leaf shine are when you’re trying to impress someone short-term. Home stagers, for example, might use leaf shine on the few potted plants they’ve placed for an open house.



What are the White Spots on My Houseplant?

White spots on houseplants are a common symptom among indoor plants in particular. Different problems can cause these white spots, some of them harmless and easy to fix. Quick, accurate identification of the underlying cause is crucial to know what, if anything, should be done. Fortunately, by considering the characteristics of the spots and your houseplant care habits, you can usually make an easy and confident diagnosis that points to one of the three potential causes.

Three Common Reasons for White Spots on Houseplants

  • Fungal Growth: These spots are a fungus that look like a thin coating or splatter of white powder. They are one of the biggest reasons we tell people to avoid excessive misting to try to raise the humidity level. More likely, you’ll just create the perfect conditions for this powdery mildew. This is one type of fungus that can tolerate the relatively dry air in most homes, but it doesn’t like a lot of light or air circulation. If you’re seeing these white spots in your low-light areas and full-shade houseplants, it’s a good bet this is your problem. Remove the current growth with a clean cloth, or just use your fingers. Use some type of fungicidal treatment, and then look for ways to increase air circulation like setting up a small fan.
  • Spider Mites, White Flies or Other Pest: Spider mites leave behind webbing designed to protect them from predators as they travel around the plant. However, many houseplant pests are also themselves white. Even common houseplant pests that are usually dark-colored, like aphids, have subtypes that are white. The white spots that are visible to the naked eye are only the full-size adults. Depending on the type of pest, the adults may or may not move. Whiteflies, as the name suggests, can fly around the plant and from plant to plant. Scale insects never move once they become adults. These insects can be removed, but some may not budge easily. You will also need to apply an insecticidal soap as well as follow-up treatments to control any eggs and larvae that may be waiting to create the next generation.
  • Cold-Water Spots: The third type of white spot on houseplants is a cold-water spot. If you have a habit of using water straight from the tap, the thermal shock of cold water can destroy palisade leaf cells and leave a white callous in its place. These cold-water spots are harmless but cannot be removed without cutting out the whole leaf. Avoid using cold water in the future, and they should cease to look like blemishes after a while. You can also try a bottom watering technique for these houseplants.

* Some people also claim that the minerals from hard tap water can accumulate and appear as white spots on leaves. We do recommend using some type of filtered or purified water for your houseplants, but we also recommend ruling out these other causes before assuming it’s mineral buildup that should be treated with a diluted vinegar solution.

White Spots in Potting Soil

Aside from leaves, white spots can also show up in your soil. The most common reason for this is also mold and fungal growth from too much misting and moisture in the top levels of soil. Known as saprophytic soil fungi, these white wispy spots are easy to remove and should respond well to fungicide and better potting soil management.

Other white spots could be a buildup of salt deposits. These types of mineral deposits look a lot different than wispy fungal growth and do not depend on organic material. Thus, even more than the soil, most people first notice these spots showing up on the edge and sides of their pot.