Houseplant apps: Planta and the others

Your monstera is yellowing, your basil is drooping, and you can no longer remember whether you watered it Monday or Thursday. Houseplant apps arrive with the solution: reminders calculated for each plant, photo diagnosis thanks to artificial intelligence and even a light meter in your phone. Useful? Often. Essential? Rarely.

We took a close look at four popular apps, Planta, Greg, PictureThis and Seek, using their Canadian App Store pages checked on October 21, 2026. Prices are those shown on those pages, in Canadian dollars. If you grow your herbs in a device, also see our comparison of smart indoor gardens, which often have their own app.

What these apps do

• Reminders: water, fertilize, mist, repot, clean the leaves.
• Identification: one photo, and the app tells you what plant it is.
• Diagnosis: one photo of a sick leaf, and the AI suggests a problem and a treatment.
• Light measurement: the app uses your phone's camera or sensor to assess the light in a corner of your home.

Planta: the most complete, and the most expensive

Designed in Sweden by Planta AB, Planta says it has more than 7 million users. Its watering reminders take into account "over 30 parameters," along with your local climate and weather, according to its website. It also offers:

• Dr. Planta, an AI diagnosis "backed by real plant data and plant experts," which suggests a step-by-step treatment plan for problems like yellow leaves or pests;
• a built-in light meter to find the best spot for each plant;
• photo identification.

The app is a free download, but its advanced features come with the Premium subscription: $10.49 for one month, $23.49 for three months or $59.99 for one year, according to its description on the Canadian App Store. It is rated 4.7 out of 5 there (about 18,000 ratings).

Greg: watering calculated from the pot

Greg, from the company Gregarious, focuses on a personalized watering calculation. Its PlantVision feature identifies the species, measures the pot and estimates the distance to the nearest window; the app then builds a watering plan based on species, size, light and pot size. It also has a community side, where you can ask other plant lovers your questions.

Photo identification is free; watering reminders and the other advanced features require the SUPER Greg subscription, which the description puts at $29.99 a year, with a 7-day trial. Rated 4.4 out of 5 on the Canadian App Store (789 ratings).

PictureThis: identification first

PictureThis, from Glority Global Group, presents itself first as an identification tool: it says it recognizes more than 400,000 species. It also offers photo diagnosis of diseases and watering reminders. Its PictureThis Pro subscription, which unlocks unlimited identifications, care tips and diagnoses, is listed most often at $49.99 on the Canadian page. It is the most popular of the four apps: 4.7 out of 5, with about 117,000 ratings.

Seek: free, and discreet

Seek is iNaturalist's consumer app, originally released with support from the California Academy of Sciences and the National Geographic Society. It identifies plants, animals and fungi, and turns observation into a game with badges and challenges. Its big advantage: according to iNaturalist, there is no registration and no user data is collected; your precise location is never stored in the app or sent to iNaturalist.

Seek does not do care reminders. But to find out what plant you received as a gift, it is an excellent starting point, as is PlantNet. We compare them in identifying a plant with your phone, and explain how to inspect your plants with Seek before bringing them in.

The comparison

Privacy labels are provided by the developers themselves; Apple notes that it does not verify them.

Watering reminders: useful to remember, not to decide

This is the core promise of these apps, and it is where the most caution is needed. A plant does not drink on a schedule: its water use changes with light, heat, the season and the size of the pot. Even a sophisticated calculation cannot see your soil.

Overwatering is the most common problem with houseplants and rots the roots, Montana State University Extension reminds us. For most herbs, Iowa State University advises letting the soil dry between waterings. The best sensor is therefore free: your finger, pushed a few centimetres into the soil. Use the app's reminder as an invitation to check, and water only if the soil is dry. A simple recurring reminder in your phone's calendar does the same job, with no subscription.

Light meters: for comparing, not measuring

A phone measures light the way the human eye does, in lux, not the light useful for photosynthesis. University of Missouri Extension points out that these units describe what our eyes see, not what plants use. An app's light meter is still handy for comparing two spots in your home, the south window versus the corner of the living room, for example. For a grow light, rely instead on the manufacturer's numbers: we explain which ones in LED grow lights: reading the real specs.

AI diagnosis: a clue, not a verdict

Dr. Planta, PictureThis and others offer to recognize a disease from a photo. Handy for steering your research, but, to our knowledge, none of these apps publishes its success rate for diseases. Independent tests of plant identification, which is simpler than diagnosis, already show errors: we summarized the University of Maryland's in what the plant ID app test reveals.

Before treating or throwing out a plant, confirm the diagnosis: take several photos following our 5-photo method, compare with a reliable source and, if needed, ask a garden centre. And if the problem comes from insects brought in from the garden, our method for bringing plants indoors without bugs will help you more than an app.

Protecting your data

• Refuse precise location if the app does not need it; an approximate location is enough for the weather.
• Read the privacy labels on the App Store or Google Play before installing. Planta and PictureThis declare data used to track you.
• Avoid creating an account if it is not necessary, and delete it when you no longer use it.
• Turn off automatic renewal of a free trial as soon as you subscribe, even if you turn it back on later.

Our advice by profile

• You have two or three plants: a recurring reminder in your calendar and the finger test are enough.
• You have a jungle of 30 plants: a tracking app like Planta or Greg may be worth its subscription, especially to log repotting and each plant's history.
• You just want to know what you have: Seek or PlantNet, both free.
• You value your privacy: Seek to identify, your calendar for reminders.

And keep your expectations realistic: a healthy plant is good for morale, but it does not purify the air in your home, as we explain in the benefits of houseplants.

Sources

• Planta (official website), Planta AB, accessed October 21, 2026.
• Planta: Plant & Garden Care (Canadian App Store page), Planta AB, accessed October 21, 2026.
• Greg: Plant Identifier & Care (Canadian App Store page), Gregarious, Inc., accessed October 21, 2026.
• PictureThis - Plant Identifier (Canadian App Store page), Glority Global Group, accessed October 21, 2026.
• Seek by iNaturalist, iNaturalist, accessed October 21, 2026.
• Growing Herbs Indoors, Aaron Steil, Iowa State University Extension, 2023.
• Pots of Possibility: Herbs that Thrive Indoors, Allison Kosto, Montana State University Extension, 2025.
• Understanding Grow Lights (G6987), Juan Cabrera-Garcia and Matt Ernst, University of Missouri Extension, 2025.