Once upon a time, identifying a plant involved trawling through books or posting an envelope of leaves to the Royal Horticultural Society. Then, it evolved into lengthy internet searching. But now, apps for mobile phones (and other devices) promise to identify your mystery plant, by way of a mere photograph. Take or load an image and, as if by magic, the plant’s name flashes up on the screen.
There are several identification apps available, so which is best? I road tested eight to find out. The following five were the winners, proving the most user-friendly and able to identify plants with accuracy:
For ease of use – Pl@ntNet
The best overall, this free app was one of the least faffy to install and use. At pace, it correctly identified the species of 15 of the 18 outdoor and indoor plants I presented to it, and, of the remaining three plants, it managed the genus of two, and the family of one. It provides a useful link to the Wikipedia page for each plant, although – in many cases – Wikipedia doesn’t offer much cultivation advice. Pl@ntNet is a citizen science project, which, as well as offering plant identification, monitors biodiversity, in turn aiding ecological research worldwide.
Cost: Free
Pros: Fast, accurate, and doesn’t bombard you with adverts.
Cons: No growing advice, other than its Wikipedia links.
For speed – Google Lens
Fuss-free, fast, and sometimes breathtakingly accurate, this app offered by Google fares well. By taking a photo or choosing one from your phone albums via the free Google Lens app, the search engine mines its vast library of pictures to deliver the best matches in an instant. This was the only app to give the correct cultivar name of an unusual scented-leaf pelargonium. It is a very simple, but effective app, producing no more than pictures in its image bank, which offer links to a mixed bag of websites: from personal Facebook pages to specialist nurseries, with the latter often detailing all the cultivation advice you need.
Cost: Free
Pros: Sometimes able to identify specific cultivars.
Cons: Not as good as others apps at identifying foliage.
For cultivation tips – PictureThis
This app correctly identified around 90% of the indoor and outdoor plants I took pictures of, and it even spotted the mildew affecting one of them. The cultivation advice is lengthy and – for the most part – sound; there are good warnings on toxicity (for example, for pets); and the app can identify weeds, as well as plant diseases. However, there are parts of PictureThis that may irritate some users – for instance, each entry has a poem with it, and it is written in American English, with US specifics (such as USDA hardiness zones). Also, some of the extensive horticultural advice is occasionally misleading or lacks information – take borage, for instance: this is an annual herb adored by bees, but, on PictureThis, it is listed as ‘annual, biennial, perennial’, and there is no emphasis on it being one of the best bee plants you can grow; some vital information (such as it performing best when sown direct) is missing; and it says the plant is ‘pest and disease free’, but then lists the pests and diseases that can attack it. So, I would be wary of using this app for foolproof cultivation advice.
Cost: Free 7-day trial, then $29.99 (around £26) per year.
Pros: Accurate identification and extensive growing advice.
Cons: The gardening advice isn’t always comprehensive.
For nature lovers – iNaturalist
A joint initiative by the National Geographic Society and the California Academy of Sciences, this is an AI technology identification system and a global community of plant experts. It is primarily geared towards wild plants, but correctly identified the garden and house plants I tested it with, naming the correct species of most. You must click ‘What did you see? View suggestions’ for the identification choices to appear, and you then choose which best resembles your photograph. The app links through to its own website, which features the Wikipedia page for each plant, and, in some instances, Wikipedia offers cultivation advice. If the AI identification tool doesn’t work or isn’t accurate enough, you can share your photograph with expert users all over the world, who will try to identify it (although their responses can take time). The app is superb at identifying plants and wildlife you see in the countryside, and submitting their location provides useful data for scientific research. iNaturalist has a great community feel and even suggests nature projects in your area.
How much it costs: Free
Pros: A great online community, with local links.
Cons: Geared predominantly towards wild plants.
For houseplants – Planta
This app is mainly for identifying houseplants (which it does very accurately) and supplying care instructions for them, but it correctly identified a lot of outdoor plants as well. There is good detail on the toxicity of indoor plants for those with pets or children; the app will notify you when plants require care (which some users might like and others could find annoying); it also has a wonderful light meter, allowing you to best choose which rooms to place specific plants. The cultivation advice for the outdoor plants is by no means as good as it is for the indoor ones, and even that isn’t as solid as it could be . . . for instance, in the case of weeping fig, it suggests that a porch might be a good home for it (but the plant dislikes drafts) and it makes no mention of leaf drop (which is the plant’s most common problem).
Cost: $7.99 (around £7) for 1 month or $35.99 (around £32) per year.
Pros: Excellent at identifying indoor plants.
Cons: Plant care advice isn’t 100% reliable.
Other identification avenues
Although the apps identified species well, they weren’t good at narrowing the plant down to a specific variety name. For example, they could tell me that the baby sage I showed them was Salvia microphylla, but failed to suggest ‘Cerro Potosí’ as the variety. For such detail, the best option is often to email a photograph to a National Collection holder or a nursery specializing in that plant type. RHS members can email plant photos to the society’s advice team, but the advisors don’t promise to identify specific varieties.
Conclusion
The apps recommended above proved reliable at identifying the majority of plants. Although they were unable to whittle them down to variety names, their accuracy at naming species was impressive. When it came to cultivation advice, most lacked it or provided it in an inaccurate or infuriating way. So, overall, for most gardeners, the best approach seems to be to use an accurate free identification app (such as Pl@ntNet or Google Lens) and then rely on books or sound horticultural web services (such as the RHS and our own pages) for foolproof growing advice.
