25 Cognitive Biases That Sabotage Plant Care

Plant care isn’t just about watering schedules and light levels—our own brain might be the biggest obstacle to keeping our plants healthy.

A cognitive bias is a systematic pattern of deviation from rational judgment or objective standards. In simpler terms, it’s a mental shortcut or tendency that causes our brains to think in predictable—but often flawed—ways. These biases arise from our brain’s attempt to simplify information processing, which can lead to errors in decision-making and perception.

For example, when caring for plants, a cognitive bias might make us favour information that confirms our existing beliefs (confirmation bias) or cause us to overlook problems because acknowledging them would be uncomfortable (the Ostrich Effect). Recognizing these biases helps us all make more informed, objective decisions in various aspects of life, including plant care.

There is some overlap in a few of these, but the ideas for most of these examples came from thousands of statements, questions, and comments on the website and in the PHA Facebook group.

By understanding these 25 common cognitive biases, we call can make better plant care decisions, stop sabotaging our plants, and grow a healthier collection.

1. Confirmation Bias: Seeing What You Want to See

What it is: The tendency to seek out and believe information that confirms what we already think while ignoring conflicting evidence.

How it affects plant care:

• You believe misting or pebble trays raise relative humidity, so you ignore the research proving these only work for a few seconds, or in a limited way.
• You assume your plant “loves” its current spot, so you dismiss signs of light stress, like yellowing or leaning.
• You think tap water is perfectly fine because your plants haven’t died yet, even though slow leaf damage from fluoride or chlorine is evident.

How to overcome it:

• Challenge your beliefs by looking for scientific evidence or experimenting with small adjustments.

2. The IKEA Effect: Overvaluing a Plant Because You Saved It

What it is: The tendency to overvalue something simply because we put effort into it.

How it affects plant care:

• You keep trying to save a plant with 90% dead leaves because you nursed it back before.
• You convince yourself that a struggling plant is actually healthy because you’ve put so much work into it.
• You refuse to throw away extra cuttings—even though you have nowhere to put them—because you propagated them.

How to overcome it:

• Ask yourself: Would I keep this plant if I hadn’t put so much effort into it?

3. The Endowment Effect: Thinking Your Plants Are More Valuable Than They Are

What it is: The tendency to assign more value to something just because we own it.

How it affects plant care:

• You refuse to replace a weak plant, even though you could get a healthier one.
• You insist your pothos is special just because it’s yours—even though there’s nothing unique at all.
• You won’t part with a plant you no longer like because you paid for it.

How to overcome it:

• Ask yourself: If this wasn’t mine, would I still think it’s special?

4. Survivorship Bias: Learning from the Lucky Few

What it is: The tendency to focus on successes while ignoring failures.

How it affects plant care:

• You see a thriving fiddle leaf fig in a dim room and assume yours will do fine—ignoring the thousands that died in similar conditions.
• You hear someone say their snake plant loves weekly watering, but you don’t hear the people who rotted theirs by over-watering.
• You see a Monstera growing well in a tiny pot and assume they prefer being root-bound, without considering how many decline in those conditions.

How to overcome it:

• Look at broad patterns of success, not just documented rare wins, or photos posted without proof of how long a plant was subjected to certain care routines or environmental conditions. The web is filled with those wanting to highlight false positives in their lives.

5. The Sunk Cost Fallacy: Refusing to Let Go of Failing Plants

What it is: The tendency to keep investing in something just because we’ve already put effort or money into it.

How it affects plant care:

• You keep nursing a half-dead plant because you already spent money on it.
• You refuse to repot a struggling plant because you “just repotted it six months ago.”
• You hold onto a plant that constantly gets pests instead of replacing it.

How to overcome it:

• Think about future success rather than past effort.

6. The Planning Fallacy: Underestimating How Long Plant Growth Takes

What it is: The tendency to believe things will take less time than they actually do.

How it affects plant care:

• You expect cuttings to root in a week when they can often take months.
• You assume a struggling plant will bounce back quickly, underestimating the time it needs to recover from a specific problem that may have taken months to be an issue.
• You think you can repot all your plants in an afternoon—then end up exhausted & frustrated.

How to overcome it:

• Be patient—plants grow on their timeline, not yours.

7. Neglect Bias: Mistaking Survival for Preference

What it is: The assumption that because a plant survives bad conditions, it must like them.

How it affects plant care:

• You think certain plants are fine with regular LED lights, or snake and ZZ plants like low light because people tell you they survive in a dark corner—but they actually thrive in the right amount of light.
• You assume your compact, root-bound plant prefers it that way, when it’s actually struggling due to competition for water and nutrients reducing growth.
• You believe your cacti enjoy being under-watered just because they can tolerate drought more easily than many other plants.

How to overcome it:

• Understand the difference between tolerance and preference—plants do best in optimal conditions.

8. Reactance Bias: Resisting Advice Just Because It’s Given

What it is: The tendency to reject advice simply because we don’t like being told what to do.

How it affects plant care:

• Someone tells you your soil is too dense, but instead of considering it, you defend your mix.
• You resist adding new lights for a leggy (etiolated) plant because “it’s my plant, and I’ll care for it how I want.”
• You hear that “banana tea doesn’t work” but refuse to stop using it.

How to overcome it:

• Pause and ask yourself: Am I rejecting this advice because it’s wrong, or because I don’t want to be told I’m wrong?

9. The Ostrich Effect – Avoiding Uncomfortable Plant Issues

What it is:

A cognitive bias that leads you to ignore or downplay negative information because it’s uncomfortable to face.

How it affects plant care:

• General Neglect: You might notice yellowing leaves, signs of pests, or other distress signals but choose to ignore them in the hope that they’ll resolve on their own.
• Lighting Conditions: You may also overlook poor lighting—believing that if the plant hasn’t visibly wilted, the conditions are acceptable—even though suboptimal light can cause long-term stress.

How to overcome it:

• Regularly monitor your plants and use objective tools (like light meters or pest detection methods) to assess their environment.
• Address issues promptly by researching and implementing appropriate adjustments, rather than hoping problems will disappear on their own.

10. The Availability Heuristic: Believing What’s Easiest to Remember

What it is: The tendency to judge something based on how easily examples come to mind.

How it affects plant care:

• You saw a viral post saying coffee grounds are great for plants, so you assume it’s true—without checking the science.
• You think root rot is the most common plant killer because that’s what everyone talks about, but underwatering is just as common.
• You assume neem oil is a miracle cure because you hear about it a lot—even though it doesn’t kill all pests.

How to overcome it:

• Double-check claims instead of trusting what’s most repeated.

11. The False Cause Fallacy: Confusing Correlation with Causation

What it is: The mistaken belief that if two things happen together, one must have caused the other.

How it affects plant care:

• You water your plant, and the next day, it perks up—so you assume it needed more water, even though light might have been the real factor.
• You see fewer gnats after using cinnamon, so you believe it works—even though drying out the soil is what actually helped.

How to overcome it:

• Consider other factors before jumping to conclusions.

12. The Law of Small Numbers: Drawing Conclusions from Too Few Examples

What it is: The tendency to assume a small number of experiences or anecdotes represent the whole truth.

How it affects plant care:

• You tried bottom watering once, and it worked, so you assume it’s the best method for all plants, in all situations.
• Your neighbour’s orchid bloomed beautifully on their kitchen counter, so you assume all orchids do fine in kitchen light—ignoring the fact that many struggle.
• You saw one person grow a Monstera in pure water, so you think soil isn’t necessary.

How to overcome it:

• One success doesn’t mean universal success—look for trends, research, and multiple experiences before drawing conclusions.

13. The Framing Effect: How Information is Worded Changes How You See It

What it is: The way something is phrased affects how we interpret it—even if the facts remain the same.

How it affects plant care:

• A product is labeled “moisture control mix”, so you assume it’s perfect for all plants, without considering that succulents need fast-draining soil.
• A fertilizer is advertised as “organic and all-natural”, so you assume it’s better—even if a synthetic alternative provides the same nutrients.
• You avoid using “chemicals” in plant care, but happily accept the use of water, oxygen, hydrogen peroxide, and neem oil—without recognizing almost everything is a chemical of some sort.

How to overcome it:

• Look at the facts and ingredients, not just how something is marketed.

14. Status Quo Bias: Preferring Familiar Methods Even When They Don’t Work

What it is: The tendency to stick with what we know, even when a better option is available.

How it affects plant care:

• You refuse to switch from peat-based soil mix to a coco-coir based better-draining mix—even though your plants struggle in peat.
• You keep fertilizing the way you always have, ignoring new evidence that less frequent feeding is better for some plants.
• You avoid upgrading to a more intense grow light because you’ve “always” relied on the one you have — despite it having a low output.

How to overcome it:

• If something isn’t actually working, don’t be afraid to change your approach.

15. The Clustering Illusion: Seeing Patterns That Aren’t There

What it is: The tendency to find patterns in random events.

How it affects plant care:

• Your plant perked up right after you talked to it, so you assume talking made it grow better—when better light or increased watering likely played a role.
• You added eggshells to your soil, and your plant grew well, so you believe eggshells boost plant health—without considering that other factors contributed.
• You only get spider mites when your plant is near a certain window, so you assume the window is causing mites—when in reality, mites are just common.

How to overcome it:

• Correlation ≠ causation—test variables before assuming connections.

16. Authority Bias: Blindly Trusting Experts Without Questioning

What it is: The tendency to believe information from an authority figure without critically evaluating it.

How it affects plant care:

• You blindly follow care instructions from a big-box store, even when they contradict best practices.
• You trust an Instagram plant influencer’s advice just because they have a lot of followers—without checking if they actually know plant science.
• A fertilizer label claims it’s “scientifically proven”, but you don’t check what the actual science says.

How to overcome it:

• Question everything—even experts make mistakes.

17. Effort Justification: Believing More Work = Better Results

What it is: The tendency to believe that more effort must mean better outcomes.

How it affects plant care:

• You over-fertilize because you assume more nutrients = more growth.
• You constantly repot plants because you think they need fresh soil every few months, even when they’re doing fine.
• You mist plants daily because it “feels” like you’re doing something helpful—even though it doesn’t meaningfully increase humidity.

How to overcome it:

• More work ≠ better results. Sometimes, doing less is doing better.

18. Time Discounting: Preferring Short-Term Gains Over Long-Term Benefits

What it is: The tendency to prioritize immediate results over future outcomes.

How it affects plant care:

• You keep your plant in a decorative pot with no drainage because it looks better—ignoring that it will have a higher risk of developing root rot over time.
• You take drastic action (like repotting) as soon as you get a plant home, instead of observing and making small adjustments first as it acclimates to your new environment.
• You buy an influencer sponsored product, fertilizer, or soil mix instead of investing in an industry proven performer, because one doesn't see quite so sexy.

How to overcome it:

• Think long-term—healthy plants take time to grow.

19. The Exposure Effect: Preferring Familiar Information

What it is: The tendency to favour things just because we’ve encountered or heard about them before.

How it affects plant care:

• You trust a myth about cinnamon killing fungus gnats because you’ve heard it so many times—despite no solid evidence (it rots and becomes food for future gnats btw)
• You assume an indoor greenhouse is essential just because lots of people show off sexy pics of their customized Ikea Milsbo cabinets.
• You hesitate to try a simpler soil mix because so many people suggest using worm castings, horticultural charcoal, unicorn turds, and pixie piss.

How to overcome it:

• Just because you’ve heard something is helpful often doesn’t mean it’s true.

20. The Halo Effect – One Positive Trait Doesn’t Tell the Whole Story

What it is:

A cognitive bias where a single appealing characteristic causes you to overestimate the overall quality or health of something.

How it affects plant care:

• General Plant Health: You might see a plant with recent large foliage growth and assume it’s thriving—even if other signs like increased node spacing, and thinner leaves indicate problems.
• Soil Quality: You could be attracted to a potting mix that advertises a great feature (such as composted forest debris, or crushed up crab shells) and assume it’s ideal, neglecting other critical factors like nutrient availability indoors or pH balance.

How to overcome it:

• Evaluate your plants holistically by considering multiple factors (leaf condition, root health, watering, light, and soil composition) rather than focusing on one standout feature.
• Cross-reference product claims with independent research and the specific needs of your plants.

21. Loss Aversion: The Fear of Letting Go

What it is: The tendency to fear losing something more than valuing what we gain.

How it affects plant care:

• You keep an infested plant way too long because you can’t bear to throw it out—even though it’s spreading pests.
• You avoid pruning a struggling plant because you don’t want to “lose” any leaves.
• You won’t repot a root-bound plant because you’re scared of transplant shock.

How to overcome it:

• Letting go of a sick plant can save your other plants.

22. The Dunning-Kruger Effect: Thinking You Know More Than You Do

What it is: Beginners overestimate their knowledge, while experts recognize how much they don’t know.

How it affects plant care:

• You watched a few YouTube or TikTok influencer videos and now confidently give plant care advice—without realizing the complexities of biology, biochemistry, light science, or hydrology.
• You assume all plants need the same care (watering volumes, soil porosity, light exposure), so you don’t bother learning individual species’ needs.
• You dismiss scientific studies or expert recommendations because you believe your personal anecdotal experience is enough.

How to overcome it:

• Stay humble and keep learning—being wrong is a good thing. Basic plant care is pretty simple, but often not easy to fully understand .

23. The Bandwagon Effect: Following Trends Without Questioning Them

What it is: The tendency to adopt behaviours simply because a lot of people are doing the same thing.

How it affects plant care:

• You start using LECA or PON because it’s trending, even though it requires a completely different care routine.
• You buy rare plants that are difficult to grow because they’re popular, even though they might not suit your home’s conditions.
• You switch to bottom watering only because everyone online says it’s best, ignoring that some plants need top watering to prevent dry pockets.

How to overcome it:

• Trends come and go—always consider your plants’ specific needs first.

24. The Zeigarnik Effect: Stressing About Incomplete Plant Tasks

What it is: We remember unfinished tasks more than completed ones.

How it affects plant care:

• You keep obsessing over a plant you haven’t repotted yet, while ignoring the thriving ones.
• You stress about a cutting that hasn’t rooted yet, constantly checking it—without realizing that growth takes time.
• You hyper-focus on a single yellowing leaf, even though the rest of the plant is perfectly healthy.

How to overcome it:

• Balance your attention—don’t let one unfinished task ruin your enjoyment.

25. The False Uniqueness Effect: Thinking Your Plant Needs Special Treatment

What it is: The tendency to believe our situation is unique and requires special exceptions.

How it affects plant care:

• You insist your fiddle leaf fig is different and doesn’t need bright light—when all research says otherwise.
• You believe your overwatered plant will recover without changing habits, even though others failed with the same mistake.
• You assume your soil doesn’t need improvement, even when your plants struggle in it.

How to overcome it:

• Your plant isn’t an exception to plant science—learn from research and experience.

Final Thoughts: Outsmarting Your Biases for Better Plant Care

Your biggest enemy in plant care isn’t pests, overwatering, or lack of light—it’s your own brain.

By recognizing these cognitive biases, you can make smarter plant care decisions and avoid common pitfalls. Instead of acting on instinct, analyze your care routine, challenge your assumptions, and adjust based on real results.

By recognizing these 25 cognitive biases, you can:

✅ Make better plant care decisions

✅ Avoid common pitfalls

✅ Challenge misleading plant care myths

✅ Stop sabotaging your plants without realizing it

Which biases have you fallen for?

Let’s discuss in the comments!