---
title: "What’s Wrong With My Plant? Houseplant Checker | Mend Petal"
description: "Tick your houseplant’s symptoms, from yellow leaves to brown tips or webbing, and see the likely causes in order, how to confirm each one and the fix."
url: https://mendpetal.me/
---

Houseplant problem checker

# What’s wrong with my plant?

Usually water, light or air rather than disease: Clemson Extension says yellowing is most often caused by overwatering, and Iowa State Extension names low humidity as the most likely cause of brown leaf tips. Tick what you see, answer five quick questions, and the chart lists the likely causes in order, how to confirm each one, and the fix.

## How the checker works

Each symptom points to a handful of causes, and the conditions you pick make some of them more or less likely. Yellow lower leaves in compost that never dries, for example, point to overwatering; the same leaves on a plant that wilts between waterings point to drought or a pot full of roots. The checker adds up those clues and shows up to five causes, most likely first.

Every cause carries a triage tag. **Watch and adjust** (green) means a change of routine will do. **Act this week** (amber) means the plant is losing ground. **Act today** (red) is for root rot, stem rot and spider mites, which spread or kill quickly. Under each cause you get the checks that confirm it, the fix step by step, and links to the extension or botanic-garden page it comes from. It is a starting point for your own checks, not a verdict.

## Rule causes out in this order

Start with the checks that cost nothing and disturb nothing, and leave the roots till last.

The four checks, quickest first: feel the compost, judge the pot’s weight, look under the leaves with a magnifier, and only then slide the plant out to see its roots.

1. **Finger test.** Push a finger into the compost. The RHS says to water when it is very dry a few centimetres down; Missouri Botanical Garden says that if you have to probe about an inch (2.5 cm) before you feel moisture, it is time to water most plants. Wet after several days means too much water or poor drainage.
2. **Lift the pot.** Dry compost is much lighter than wet. Learning the weight of your pot just after watering makes this quick (Missouri Botanical Garden).
3. **Look under the leaves.** Pests sit on the undersides, in leaf joints and on new growth, and a 10× magnifying lens makes small ones far easier to see (Clemson). Look at the compost and pot rim too: a hard white crust is fertiliser salt; soft fuzz is mould on wet compost.
4. **Check the roots.** Hold the plant, turn the pot over and tap the rim on a table edge (NC State). Healthy roots are white or light-coloured and firm; rotted roots are brown or black, soft and may smell (UC IPM, Maryland Extension).

## A worked example: yellow lower leaves, damp soil

The chart above starts with a common winter case: a few lower leaves turning yellow, compost still damp, watered little and often, bright light, nothing moved, heating on. Overwatering comes out on top because it fits every answer: damp compost, frequent watering and the slow growth of winter all point the same way. Normal ageing comes next, because the RHS says the odd lower leaf on a mature plant yellows and falls naturally.

To tell them apart, do the finger test over the next few days. If the compost stays wet and more leaves yellow, cut back: water only when the top few centimetres are dry, empty the saucer, and water less until spring, since plants need less water and fertiliser in winter (NC State). If the compost dries normally and only one old leaf at a time goes, it is just age.

## Common mistakes

- **Watering a wilting plant that is already wet.** Overwatered roots rot and stop taking up water, so the plant wilts and looks thirsty. Missouri Botanical Garden calls another watering at that point the death knell. Feel the compost first.
- **Watering on a set day.** Both the RHS and University of Maryland Extension advise checking the moisture and watering only when the plant needs it.
- **Potting into a much bigger pot.** The extra compost stays wet, and the RHS says the yellowing and leaf fall that follow are often mistaken for thirst. Go up one size, about 5 cm (2 in) wider (Missouri Botanical Garden).
- **Misting for humidity.** NC State finds misting raises humidity only briefly; grouping plants, pebble trays or a humidifier work better.
- **Homemade sprays.** UC IPM does not recommend homemade pesticides, dish-soap recipes included. Use products labelled for indoor plants and follow the label.

## Why problems show up in November and December

Winter light is weaker and shorter, so houseplants grow less and need less water and feed (NC State); keeping summer watering habits is the usual route to soggy compost. Heating dries the air, and NC State notes heated homes can sit at 10 to 15% relative humidity, which browns leaf tips and suits spider mites. Cold glass is the other hazard: keep leaves off winter window panes, move plants about 15 cm (6 in) into the room, and do not shut windowsill plants behind curtains on frosty nights (Missouri Botanical Garden, NC State, RHS). Bringing a new plant home in the cold? Wrap it for the journey.

General information from the extension and botanic-garden pages listed below, not professional advice. If a pet or child may have eaten part of a plant, see [plants toxic to cats and dogs](https://mendpetal.me/plants-toxic-to-cats-and-dogs/) for poison helpline numbers.

## More plant clinic tools

Each one answers a question people search for most, with the default example already worked out.

- [Why are my plant leaves turning yellow?](https://mendpetal.me/why-are-my-plant-leaves-turning-yellow/): Lower, new or all over: what each pattern means, with a picture guide.
- [Brown tips on plant leaves](https://mendpetal.me/brown-leaf-tips/): Dry air, salts, fluoride, watering, sun or cold: find which one.
- [Houseplant pest identifier](https://mendpetal.me/houseplant-pest-identifier/): A picture key to seven pests, each with a treatment ladder and weekly re-checks.
- [Christmas cactus not blooming](https://mendpetal.me/christmas-cactus-not-blooming/): A bloom planner: when to start long nights for flowers on your date.
- [Poinsettia care and rebloom](https://mendpetal.me/poinsettia-care/): The trip home, keeping it to January, and next year’s calendar.
- [Plants toxic to cats and dogs](https://mendpetal.me/plants-toxic-to-cats-and-dogs/): Search 64 plants as the ASPCA lists them, with helpline numbers.

## Recommended

Two free tools from elsewhere that plant lovers find handy.

For care guides and discount codes

### CleanTempMail

Plant shops and garden centres often want an email address before you can download a care sheet or claim a code. CleanTempMail gives you a free temporary inbox instantly, with no sign-up, and its emails are deleted automatically after 3 days. Keep your real address for orders and delivery updates.

[Open a free temporary inbox](https://cleantempmail.com/)

For unfamiliar plant shops

### WebTraceCheck

Found a rare plant on a website you have never heard of? WebTraceCheck’s free DNS and domain lookup shows what is behind a domain, and its disposable cloud browser opens the shop in Chrome, Firefox or another browser on an isolated desktop that is deleted after the session, with nothing to install.

[Try the disposable browser](https://webtracecheck.com/)

## Frequently asked questions

**Why are my plant’s leaves turning yellow and brown?**

Yellow leaves that then turn brown and drop usually come back to watering. Clemson Extension says yellowing is most often caused by overwatering, while the RHS notes that a plant left too dry yellows its lower leaves first, with crisp brown edges. The finger test tells you which.

**How do I know if I am overwatering my plant?**

The compost stays wet a few centimetres down for days, the pot feels heavy, water sits in the saucer, and old and new leaves yellow together. If it also wilts while wet, check the roots for brown, soft rot.

**Can a plant recover from root rot?**

If only some roots are rotten, cut them off and repot in fresh mix in a pot with drainage holes. If most roots are dark, soft and dead, Clemson advises discarding the plant; take cuttings from healthy stems first.

**Should I cut off yellow or brown leaves?**

Yes, once a yellow leaf comes away easily. For brown tips, NC State suggests trimming off the dead part but leaving a thin brown edge, rather than cutting into green tissue. Trimming is cosmetic: fix the cause or new tips will brown.

**Does the checker store or send my answers?**

No. It runs entirely in your browser and nothing you tick is sent anywhere. The site counts page views with cookie-free Cloudflare Web Analytics, which never sees your answers.

## Sources

Every cause, check and fix comes from these pages, all opened and checked on 3 November 2026.

1. [Houseplant Diseases & Disorders (HGIC 2251)](https://hgic.clemson.edu/factsheet/houseplant-diseases-disorders/). Clemson Cooperative Extension, Home & Garden Information Center, updated 28 February 2025.
2. [Common Houseplant Insects & Related Pests (HGIC 2252)](https://hgic.clemson.edu/factsheet/common-houseplant-insects-related-pests/). Clemson Cooperative Extension, Home & Garden Information Center, updated 10 September 2021.
3. [How to help a poorly houseplant](https://www.rhs.org.uk/plants/types/houseplants/how-to-help-a-poorly-houseplant). Royal Horticultural Society.
4. [Leaf damage on houseplants](https://www.rhs.org.uk/prevention-protection/leaf-damage-on-houseplants). Royal Horticultural Society.
5. [Overpotting](https://www.rhs.org.uk/prevention-protection/overpotting). Royal Horticultural Society.
6. [How to take cuttings from houseplants](https://www.rhs.org.uk/plants/types/houseplants/how-to-take-cuttings-from-houseplants). Royal Horticultural Society.
7. [Environmental Problems of Indoor Plants](https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/insects-pests-and-problems/environmental/environmental-problems-of-indoor-plants). Missouri Botanical Garden.
8. [How to Water Indoor Plants](https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/visual-guides/how-to-water-indoor-plants). Missouri Botanical Garden.
9. [Extension Gardener Handbook, chapter 18: Plants Grown in Containers](https://content.ces.ncsu.edu/extension-gardener-handbook/18-plants-grown-in-containers). NC State Extension, 1 February 2022.
10. [Diagnosing Poor Plant Health](https://extension.psu.edu/diagnosing-poor-plant-health). Penn State Extension, updated 29 June 2026.
11. [Pest and Disease Problems of Indoor Plants](https://extension.psu.edu/pest-and-disease-problems-of-indoor-plants). Penn State Extension, updated 12 October 2026.
12. [Pest Notes: Houseplant Problems (Publication 74172)](https://ipm.ucanr.edu/home-and-landscape/houseplant-problems/). UC Statewide IPM Program, University of California, updated August 2020.
13. [Watering Indoor Plants](https://www.extension.umd.edu/resource/watering-indoor-plants). University of Maryland Extension, updated 10 March 2023.
14. [Root Rots of Indoor Plants](https://extension.umd.edu/resource/root-rots-indoor-plants). University of Maryland Extension, updated 13 March 2023.
15. [Diagnose Indoor Plant Problems](https://extension.umd.edu/resource/diagnose-indoor-plant-problems). University of Maryland Extension, updated 5 February 2025.
16. [Algae and Fungal Growth on the Soil of Indoor Plants](https://extension.umd.edu/resource/algae-and-fungal-growth-soil-indoor-plants). University of Maryland Extension, updated 13 March 2023.
17. [Powdery Mildew on Indoor Plants](https://extension.umd.edu/resource/powdery-mildew-indoor-plants). University of Maryland Extension, updated 13 March 2023.
18. [Diagnosing Houseplant Problems from Improper Environmental Conditions](https://yardandgarden.extension.iastate.edu/how-to/diagnosing-houseplant-problems-improper-environmental-conditions). Iowa State University Extension and Outreach, reviewed January 2024.
19. [How can I determine if my houseplant has spider mites?](https://yardandgarden.extension.iastate.edu/faq/how-can-i-determine-if-my-houseplant-has-spider-mites). Iowa State University Extension and Outreach, updated 4 March 2022.
20. [How to grow Swiss cheese plants](https://www.rhs.org.uk/plants/swiss-cheese-plants/how-to-grow-swiss-cheese-plants). Royal Horticultural Society.
21. [Philodendron, Pothos & Monstera (HGIC 1509)](https://hgic.clemson.edu/factsheet/philodendron-pothos-monstera/). Clemson Cooperative Extension, Home & Garden Information Center, revised 15 January 2016.
22. [Tips for Repotting Houseplants](https://extension.illinois.edu/blogs/good-growing/2018-03-19-tips-repotting-houseplants). University of Illinois Extension, 19 March 2018.