A fern reference for iPhone
Most plant apps want a photograph and give you a guess. FernsBook does the opposite: it is a small, finished, hand-written reference — thirty-seven species you can actually buy, each one described across eleven care panels and closed out with a curator note that says what usually goes wrong. It ships complete inside the app, so it reads the same on a plane as it does in a nursery car park.
Adiantum raddianum
The library
The grouping is the opinion. A fern in the Indoor shelf is there because it will survive a heated living room, not because it can technically live in a pot. Every entry also carries one of four difficulty grades, which is the honest bit — some of these plants are unforgiving and the app says so.
Boston, Bird's Nest, Maidenhair, Blue Star, Button, Rabbit's Foot and the rest of the houseplant bench.
Shade-border workhorses — Autumn, Japanese Painted, Holly, Kimberly Queen — that earn their place in a bed for years.
Woodland species with a real range: Ostrich, Royal, Cinnamon, Lady, Western Sword, Hart's Tongue, Licorice.
The ones that need a mount, a glasshouse or a lot of nerve: Staghorn, Soft Tree Fern, Australian Tree Fern, King Fern.
Inside one entry
Every species is written to the same eleven headings, so you can compare two ferns line for line instead of re-reading two essays. Then the curator note breaks format and tells you the one thing that decides whether the plant lives — for the Maidenhair, that a single dry spell collapses it; for the Bird's Nest, that water sitting in the crown rots the new growth.
FernsBook is written, not photographed. There are no species photos in the app — identification is done in words, through habit, frond shape and range. If you want a picture library, this is the wrong app, and we would rather say that here than in a refund request.
Search and notes
Search runs across every field of every entry at once — common name, botanical name, range, soil, the warnings, the curator notes. So humid bathroom, dry shade or mounted all find something, and the collection chips narrow it to one shelf.
The fern coach
Open a species, type a real question, and FernsBook sends it — with that fern's name and collection attached, so the answer is about your plant and not ferns in general — to the app's own service, which writes a reply and sends it back. Nothing else about you goes with it: not a name, not an account, because there isn't one.
Three questions a day are free. If the answer can't be fetched — you're on a plane, or the service is having a bad afternoon — the app assembles a fallback out of that species' own light, water, humidity, soil and watch-out panels, and tells you it did.
It is a reading and growing aid. It does not identify plants, and it will not answer questions about toxicity, foraging or anything medical.
“Why are the frond tips browning?”
Asked on the Boston Fern entry. Tip burn on Nephrolepis exaltata is almost always air, not soil: the root ball dried once, or the room sits under about 50% humidity. Water before the mix dries through, group it with other plants or move it to a bathroom, and cut the spent fronds at the base rather than trimming the brown edges.
What leaves your phone
A reference app has no business collecting anything, so FernsBook doesn't. There is nothing to sign into, so there is no identity to attach anything to. The complete list of what travels is short enough to put on this page.
Pricing
All thirty-seven species, all eleven panels, search and private notes are free and need no account — that is the whole reference and it is not on a trial. Pro adds the record-keeping side of the app and lifts the cap on coach questions, which are counted because each one costs us money to answer.
FernsBook
$0No account, no card, nothing to cancel.
FernsBook Pro
US$4.99 / month · US$19.99 / yearAuto-renewing. Prices vary by storefront; your local App Store price is shown before you confirm.
Three things, and that is the whole list. Everything else described on this page — the library, the eleven panels, search, and writing and reading your notes — is free on both tiers and stays that way.
Payment is charged to your Apple Account at confirmation of purchase. The subscription renews automatically unless auto-renewal is turned off at least 24 hours before the current period ends; manage or cancel it in your App Store account settings. Full detail in the Terms of Use and Apple's Standard EULA.
Before the next one dies
Requires iPhone. Something unclear? Ask us first.