Two rooms, a bench and a notebook
Iron Fern opened in October 2016 in what had been a bike repair shop, which explains the floor drain and the chain-oil smell that took two winters to quit. It is still two rooms, and still a small number of plants kept properly rather than a big number kept briefly.
Why the journal exists
We started writing things down because we kept contradicting each other. One of us would tell you a snake plant wants water every two weeks; the next week the other would say every two months. Both of us were repeating something we had read instead of something we had watched happen on a bench three feet away.
So in 2018 we set a ledger on the counter and started recording the date every pot in the shop got watered, what the room was doing at the time, and what the plant did afterward. The guides on this site are that ledger, tidied up. Where a number here argues with the tag in your pot, go with ours — it was measured in this building.
It is also why you’ll find our failures here. The maidenhair profile exists mostly because we lost eleven of them in four days after handing out confident advice that turned out to be wrong.
Who is here
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Nell Ostrowski
Owner · writes most of the journal
Came to plants sideways, by way of eleven years in restaurant kitchens and a balcony that faced the wrong direction. Handles repotting, the ledger, and any conversation that opens with “I know I’ve ruined it.”
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Devon Achebe
Buying & the back room
Deals with the growers, drives the van, keeps the cuttings bench. If a plant on the shelf looks better than it did last month, you are looking at Devon’s work.
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Saturday counter
Rotating
Two neighbors who have worked Saturdays since 2019 and know the stock better than we care to admit. They are the reason you can come by on a weekend at all.
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The shop cat question
Asked daily
No cat. There was a cat. She retired to a house over on Belmont in 2021 and is, by every report we get, extremely comfortable.
What we stock, and what you won’t find
Around forty kinds at a time, most of them grown on in the back room for at least six weeks before they reach the front. We buy small and pot up ourselves, so a plant you carry home has already survived a season of the light it is being sold into.
Things you won’t find here, and why:
- Maidenhair ferns in summer. No house in this city is humid enough in July, and it would not be fair to you or to the fern.
- Anything dyed, glittered or glued into a pot. The glue is usually hiding a root problem.
- Pots with no drainage hole. Ask, and we will sell you a handsome cachepot to drop a nursery pot down inside instead.
- Very large specimens. We have no way to keep one well for the months it would take to sell, and a stressed six-foot plant is an expensive thing to take home.
We do take cuttings off the shop’s own plants and sell them rooted and cheap in 4″ pots. The pothos on the front bench has probably furnished a hundred households by now, and yours can be next.
Our potting mix
You ask for this constantly, so here it is. It is not a secret and it is not clever — it is simply much more open than the peat-heavy stuff sold in bags, which is what most houseplants in this climate actually want.
- 4 parts
- Coir, or a good peat-free potting soil
- 3 parts
- Orchid bark, fine grade, sieved
- 2 parts
- Pumice (perlite works; it floats and migrates)
- 1 part
- Worm castings
- A handful
- Horticultural charcoal, per bucket
- Makes
- About enough for six 6″ pots
Adjust from there rather than mixing a second batch. For a snake plant or a ZZ, add pumice until it is roughly half grit. For a calathea or a fern, add coir until it holds damp longer. For a hoya, go the other way entirely: mostly bark and pumice, with just enough mix to hold it together.
Pot size. One size up, never two — about an inch of new soil all the way around. Move a plant from a 4″ to an 8″ and its roots are sitting in a big volume of wet soil they cannot reach, which is root rot waiting for February. Most plants want this once every two or three years, in spring, and are perfectly content crowded in between.
The repotting bench, in order
- Water the plant the day before — a dry root ball breaks up badly on you.
- Tip it out sideways. Never pull a plant up by the stem.
- Tease the bottom third loose and cut away anything soft, black or hollow.
- Put two inches of mix in the new pot and set the plant at the depth it was before.
- Fill in around the sides and tap the pot down — do not press with your thumbs.
- Water it thoroughly once, then leave it alone for two weeks.
You’ll want to hold off on fertilizer for six weeks after a repot. There is food in the castings, the roots are damaged, and feeding a damaged root system is how you end up with burned tips on top of everything else.
The building
The front room has the south window and the double doors that make it usable in summer and honest in winter. The back room — the old workshop — has a small north window, a corrugated roof and no heat at all; it drops to about 50 °F on a January night. That room is why we are confident about the long winter intervals in the watering table: the plants in it barely grow from November on, and they are the healthiest plants we own.
There is a rain barrel behind the shop, fed off the workshop roof, and that is what the calatheas drink. Through a Portland winter it never runs dry. In August it does, and we go back to tap water left standing overnight in a bowl.
We went through this page on February 3, 2025.