The Greenhouse in Agia Galini
Yannis met her at the airport with the truck that had a crack across its windshield he had been meaning to replace since March. He took her bag and put it in the back beside a crate of tomato seedlings and a box of glass slides, and she said, “Baba, you still drive this thing?” and he said, “It goes where I need it to go,” which was the whole argument in one sentence, and they did not have it yet.
The greenhouse sat on a slope above the town, glass and polycarbonate patched with tape and shade cloth, six rows of raised beds and a workbench at the back where the oscilloscope lived under a tarp. Yannis had built the bench himself from a door he’d taken from a demolished house in Rethymno. The oscilloscope was older than Liora. He had bought it at a university surplus sale in Athens in 1994, and it still worked.
Liora set her bag on the cot in the corner of the greenhouse where she would sleep and looked at the plants. Tomatoes, mostly. Some peppers. A row of basil that had gone to flower, which she would have told any student was a mistake but did not tell him. The plants were in pots and in beds, and between many of them ran the white thread of fungal hyphae, visible at the soil surface where the watering had been light. She saw that and did not comment, because commenting would start the week.
“I need the greenhouse empty by the twenty-second,” she said. “The buyer’s lawyer is in Heraklion. I have a flight on the twenty-third.”
“I know the calendar,” Yannis said.
He was seventy-one. He had been a plant physiologist at the University of Crete for thirty-one years and had retired in 2019 with a pension and a grievance. The grievance was specific. In 2014 he had published a paper in a journal with a small impact factor, arguing that electrical signals recorded in the roots of tomato plants under aphid attack were not stress artifacts but transmitted information, and that the receiving plant’s change in volatile emissions could not be explained by shared air or shared soil chemistry. The paper had been cited eleven times, nine of them by people calling it methodologically flawed. A colleague at the university, Konstantinos, had said at a department meeting that Yannis was “doing plant neurobiology without the neurobiology,” which was a good line and which Yannis had never forgotten, because it was the kind of line that sounds clever and means nothing and still ends a career.
He had retired and come to this greenhouse and kept measuring.
Liora was thirty-eight. She was an agronomist at the Agricultural University of Athens, tenure-track, and she had a paper due in September on drought stress in olive cultivars that she was behind on. She was also angry, though she would not have used the word. She was angry at the greenhouse because it was six years of her father’s life that could have been spent on anything else, and she was angry at herself for being angry, because she knew what the greenhouse was. It was the place where he had gone after Konstantinos, after the department, after the paper.
She had not slept in the greenhouse since she was fourteen.
“Show me the setup,” she said.
He showed her. The receiver plant sat in a pot on the bench, a tomato, variety Santorini, with a soil moisture sensor and a pair of silver/silver chloride electrodes inserted at the root crown, wired to the oscilloscope. Beside it, separated by a polycarbonate barrier that did not seal, sat the sender plant, also Santorini, also potted. The sender’s pot was open to the air. The receiver’s pot was open to the air. The barrier between them was waist-high and meant to block aphids from walking from one plant to the other, which was the kind of thing that sounds like it would work until you think about it for thirty seconds.
“The barrier doesn’t seal,” Liora said.
“It doesn’t need to seal. The aphids don’t walk across a barrier. They fly, or they don’t. The point is the roots.”
“The point is that air moves over the top of the barrier and the volatiles from the infested plant reach the receiver through shared air, and you know that, and you’ve known it for six years.”
Yannis looked at her. He had her mother’s eyes. “The controls address shared air.”
“Show me the controls.”
He showed her. There were three conditions, run in sequence over the week. Condition A: sender and receiver connected by mycorrhizal hyphae, sender infested, receiver’s volatiles measured. Condition B: sender and receiver in shared soil with hyphae severed, sender infested, receiver measured. Condition C: sender and receiver in shared air with no soil contact, sender infested, receiver measured. The hypothesis was that only condition A would show the change in volatile emissions, because only condition A had the mycorrhizal connection through which the electrical signal could travel.
“The severance,” Liora said. “How.”
“Blade. Shallow cut through the soil between the pots. Cuts the hyphae without damaging the roots.”
“You’ve tested that the roots survive the cut.”
“I’ve tested it.”
“Show me the data.”
He showed her. The data was in a notebook, handwritten, six years of it, and she sat at the bench and read it looking for the hole. The hole was there. In condition B, the severed-hyphae condition, the receiver’s volatile emissions did change, slightly, in some runs. Not as much as condition A. But some. Yannis had noted it in the margin of the notebook with a question mark and had not mentioned it in the paper, because the paper said the change occurred only with intact hyphae, and the notebook said otherwise.
“You didn’t report the B condition positives,” she said.
“They were within noise.”
“They were not within noise. Look at run fourteen. Look at run twenty-two. Those are real changes, Baba. Small, but real. And they’re in the condition where the hyphae are cut.”
Yannis sat on the stool by the bench. He did not look at her. He looked at the oscilloscope under its tarp.
“The B condition positives are from shared soil chemistry,” he said. “Root exudates diffuse through soil water. That’s not information transfer. That’s chemistry.”
“Then report them as chemistry. Report them as a confound. The paper says the signal arrives only with intact hyphae. The notebook says the signal arrives, slightly, without hyphae. Those are different claims.”
“The paper is a summary.”
“The paper is a claim. And the claim is wrong, or at least incomplete, and you know it, and you’ve known it for six years.”
He did not answer. She sat with the notebook open and felt the anger move through her, and she thought: Not the experiment. The notebook. The margin notes. The question marks that were never answered because answering them would have meant the paper was not what he said it was, and the paper was all he had.
She closed the notebook.
“We run it again,” she said. “All three conditions. I design the controls. You do the measurements. And we report everything, including the B positives, whatever they turn out to be.”
“And if the B positives are real?”
“Then they’re real, and we say so.”
“And if they’re not? If they’re noise, and the only real signal is in A?”
“Then that’s what we report.”
“And if A shows nothing at all?”
She considered it. “Then A shows nothing, and we report that too.”
He nodded slowly. She nodded too, without knowing she was doing it.
“Tomorrow,” he said. “We set up tomorrow. The aphids are on the peppers.”
The aphids came from a pepper plant in the corner of the greenhouse that Yannis had been keeping for exactly this purpose. It was infested, badly, the leaves curled and sticky, and he had not treated it because he needed a source of aphids for the experiment. The peppers were not part of the experiment. They were part of the greenhouse. They were part of him.
She set up the conditions on Monday morning. She had brought equipment from Athens: a portable gas chromatograph, a set of volatile collection traps, a laptop with the analysis software. She had also brought, in her bag, a copy of her tenure file, which she did not need for the experiment but which she had brought because it was the thing the experiment threatened, and she wanted to be able to look at it and remember what was at stake. The tenure file was not a thing she talked about. It was a folder on her laptop, and it contained a paper she owed, and the paper she owed was on drought stress in olive cultivars, and it was due in September, and September was three months away, and she was here in a greenhouse in Crete running an experiment on tomato plants that might or might not show what her father had spent six years claiming.
She did not tell him about the tenure file. She did not tell him about the paper. She told him about the gas chromatograph and the volatile traps and the software, and he listened with his whole body turned toward her and his mouth slightly open, and she had always found the intensity of his attention alarming.
The first condition was A. Sender and receiver, mycorrhizal connection intact. She infested the sender with aphids from the pepper plant, placing them on the leaves with a fine brush, and Yannis recorded the electrical signals at the receiver’s root crown. The oscilloscope traced a line that was mostly flat and occasionally spiked, and the spikes came at intervals that Yannis timed with a stopwatch and wrote in the notebook.
“The first spike is at four minutes,” he said. “After infestation.”
“Four minutes from aphid placement to root signal.”
“Yes.”
“And the volatile change?”
“We measure at twenty-four hours.”
“Why twenty-four?”
“Because that’s when the previous runs showed the change. The receiver’s volatile profile shifts at roughly eighteen to twenty-four hours after the sender is infested.”
“Eighteen to twenty-four hours for an electrical signal to travel from roots to leaves to volatiles.”
“The electrical signal travels fast. The volatile change is the plant’s response. The response takes time.”
She wrote this down. She did not say that eighteen to twenty-four hours was also the diffusion time for volatile organic compounds through a greenhouse of this size, which was the confound that had haunted the original paper, and which Yannis knew about, and which was why the controls mattered.
They ran condition A on Monday and Tuesday. The receiver’s volatile profile shifted. Yannis showed her the chromatogram, and she looked at it, and the shift was there: a change in the emission of methyl salicylate and (Z)-3-hexenyl acetate, the compounds that tomato plants release when they are under attack, the ones that warn neighboring plants to prime their defenses. The shift was real. She could see it on the screen.
“Now condition B,” she said.
Condition B was the severed hyphae. Yannis took the blade, a scalpel, and made a shallow cut through the soil between the pots, and Liora watched the blade go in and felt something she did not expect, which was that the cut looked like a wound. It was a cut in dirt. It was a cut in fungal thread. It was nothing. But it looked like a wound, and she thought: this is what he has been doing for six years. Cutting the thing between the plants to see if the thing between the plants is what carries the signal. And the thing between the plants is alive, and the cut kills it, and he has done this hundreds of times, and she understood now that the experiment was not only about information transfer. It was about whether you could cut the connection and still have the conversation.
They ran condition B on Wednesday and Thursday. The receiver’s volatile profile shifted again. Smaller than condition A. But there. Liora sat with the chromatogram and looked at it for a long time.
“It’s there,” she said.
“It’s there,” Yannis said.
“It’s smaller.”
“It’s smaller.”
“So the hyphae are not the only pathway.”
“The hyphae are the primary pathway. The soil chemistry is secondary.”
“Or the hyphae are one pathway and the soil chemistry is another, and they’re both real, and the paper should say that.”
Yannis did not answer. He wrote the numbers in the notebook, and she saw that he wrote them in the same handwriting, the same careful numerals, but slower, as if the numbers were heavier than they had been on Monday.
On Thursday night they ate dinner in the greenhouse. Yannis had made dakos, barley rusks with tomato and feta and oregano, and they sat on the bench and ate and did not talk about the experiment. Liora asked about the peppers, and Yannis said they were doing fine, which was not true, and she did not say so. She asked about the town, and he said it was the same, which was also not entirely true but was close enough. She asked about his knee, which had been bad since winter, and he said it was better, which was a lie, and she let it be a lie because it was the kind of lie that is not about the knee.
“Baba,” she said.
“Yes.”
“The B condition. The positives. You knew.”
He set down his fork. “I knew they were there. I did not know what they meant.”
“They meant the paper was incomplete.”
“They meant the paper was incomplete. Yes.”
“And you didn’t revise it.”
“I did not revise it. No.”
“Why.”
He looked at the oscilloscope under its tarp. “Because the paper was what I had. It was the only thing. If I revised it, it would have been a different paper, and the different paper would have said that the signal is partly chemistry, and partly something else, and we don’t know which part is which. And that paper would not have been cited eleven times. It would have been cited zero times, because it would have said nothing. And I needed the paper to say something, because the paper was the only thing between me and Konstantinos saying I was doing plant neurobiology without the neurobiology.”
Liora put down her fork. She looked at her father, who was seventy-one and had bad knees and a truck with a cracked windshield and a greenhouse full of tomato plants that he had spent six years talking to, and she thought of the paper that said something when the truth was that he didn’t know, and knowing that he didn’t know was the thing he could not carry.
“I’m not going to publish it either way,” she said. “The experiment. I’m not going to write it up.”
“I know.”
“I’m not going to write it up because it doesn’t show what you said it showed, and it doesn’t show what I said it wouldn’t show. It shows something in between, and the something in between is not a paper. It’s a question.”
“Yes.”
“And I have a paper due in September. On olive cultivars. Drought stress. It’s a real paper, and it’s good, and it’s the one that matters for my tenure file, and I am here in your greenhouse running an experiment on tomatoes instead of writing it.”
Yannis looked at her. “I know about the tenure file.”
“You know about the tenure file.”
“You left it on the bench. The folder. I didn’t open it.”
She closed her eyes. “Of course you didn’t.”
“I didn’t need to. I know what it is. I know what it costs you to be here.”
“It costs me a paper.”
“It costs you more than a paper.”
She opened her eyes. He was looking at her with his whole body turned toward her, and she felt the thing she had been avoiding all week, which was that she loved him and that loving him was not the same as agreeing with him and that the greenhouse was not a wound she could heal by emptying it.
“I’m not selling it,” she said.
“What?”
“I’m not selling the greenhouse. I’m not signing the papers. You keep it.”
“Liora—”
“You keep it. You keep the tomatoes and the peppers and the oscilloscope and the notebook. You keep running the experiment. But you report the B positives. You revise the paper. You say what you know, which is that the signal arrives through the hyphae and also through the soil, and you don’t know which part is information and which part is chemistry, and that’s the paper. That’s the real paper. And it won’t be cited eleven times. It might not be cited at all. But it will be true.”
He sat with this for a long time. The greenhouse was quiet except for the sound of the ventilation fan and the night insects outside.
“And if the true paper is not enough?” he said.
“Then it’s not enough. But it’s yours.”
Friday was condition C. Shared air, no soil contact. She had set up two plants on opposite sides of the greenhouse with a fan between them to ensure air circulation, and she infested the sender and measured the receiver. The volatile profile did not change. Not at twenty-four hours, not at forty-eight. The receiver was unaffected. Shared air alone was not enough.
“So air doesn’t carry it,” she said.
“Air carries VOCs. But the VOCs from an infested plant don’t trigger the same response in a receiver that’s not connected. The signal is not in the air. It’s in the roots.”
“Or the signal is in the air but the receiver needs to be primed by a root signal to respond to it.”
“That’s the same thing.”
“No. It’s not. If the receiver needs the root signal to respond to the air signal, then the air signal is not the message. The root signal is the message. And the air signal is just air.”
Yannis wrote this down. She saw him write it, and she saw that he wrote it in the margin, next to the question mark, and that the margin was getting full.
Saturday was the last day. She ran condition A again, a repeat, and the result was the same: volatile shift, electrical spikes at four minutes, the whole sequence. She measured it, and he measured it, and they sat at the bench and looked at the numbers.
“So,” she said.
“So,” he said.
“The signal arrives through the hyphae. It arrives, weakly, through the soil. It does not arrive through the air. The electrical propagation in the roots precedes the volatile change by roughly eighteen hours. And we cannot say whether the electrical signal is information or whether it is a stress response that happens to travel through the same pathway as the chemical signal.”
“No,” he said. “We cannot.”
“And the B positives are real.”
“They are real.”
“And they are not in the paper.”
“They are not in the paper. They will be.”
She closed the laptop. “I’m not writing this up.”
“I know.”
“I’m not writing it up because it’s not my experiment. It’s yours. And you need to write it. The real version. With the B positives and the uncertainty and the question marks in the margins, except the question marks should be in the text, because the question marks are the finding.”
He nodded. She could see that he was tired, and that the tiredness was not only physical, and that the week had cost him something she could not name.
“Tomorrow I go,” she said. “The flight is at noon.”
“I know.”
“I’ll leave the equipment. The gas chromatograph. You can use it.”
“I know how to use it.”
“I know you know. I’m saying I’m leaving it.”
He looked at her. “Why.”
“Because you need it more than I do. And because I want you to keep going. And because—” She stopped. She did not finish the sentence. She did not know how to finish it. The sentence was about love, and love was the thing between them that they measured the world to avoid saying, and she could not say it now, not here, not in the greenhouse, not with the oscilloscope under its tarp and the notebook open on the bench.
“Because,” she said, and stopped again.
“Because,” he said, and did not finish either.
They sat there. The fan hummed. The plants were still. Outside, the night was dark and the sea was somewhere below them, and she could hear it if she listened, which she did, and he did too, and that was enough for now.
Sunday morning. Early. The light came through the polycarbonate in long slats, and the greenhouse smelled like tomato and earth and the particular smell of a place that has been lived in. Liora packed her bag. She left the gas chromatograph on the bench, next to the oscilloscope, and she left the volatile traps and the software on the laptop, which she left too, because she had her own laptop in Athens and he did not have one here. She left the tenure file in her bag. She took it with her. It was hers.
Yannis was at the sink, washing the coffee cups. He had made coffee, Greek coffee, thick and sweet, and they had drunk it standing up, and now he was washing the cups because that was what he did in the morning, and she watched him do it and thought: this is the last morning. This is the morning I leave, and the greenhouse stays, and he stays, and the plants stay, and the experiment stays, and I go back to Athens and my paper and my tenure file and my life, and he stays here with the oscilloscope and the notebook and the question marks.
She picked up her bag. “I’ll call from the airport.”
“Call from the plane. They let you do that now.”
“They don’t let you do that. That’s not a thing.”
“It’s a thing. I read it.”
“You read a lot of things.”
He smiled. It was a small smile, and it was the kind of smile that she had seen her whole life and that she had never been able to read, and she could not read it now.
She walked to the door of the greenhouse. The door was wooden, swollen with humidity, and it stuck, and she pushed it open with her shoulder, and the morning air came in, warm and smelling of thyme and the sea.
She stopped at the gate.
The receiver plant, from condition A, sat in its pot on the bench where they had left it. It was a tomato plant, Santorini variety, about forty centimeters tall, with compound leaves that were slightly curled at the edges, which was normal for this variety in this heat. She had looked at this plant every day for a week. She knew its leaves. She knew their angle, their curl, their position relative to the stem.
The leaves had changed.
Overnight, or in the early morning, the leaves on the receiver plant had shifted. They were angled now, tilted toward the sender plant, the one that had been infested, the one that sat two meters away on the other side of the polycarbonate barrier. The sender plant was not infested anymore. The aphids had been removed on Friday. The sender was clean. But the receiver’s leaves were turned toward it, as if listening, as if the conversation had not ended when the aphids were removed, as if the plant was still waiting for a signal that might come.
Liora stood at the gate with her bag on her shoulder and looked at the plant. She had no notebook, no laptop, no gas chromatograph. She had a bag with clothes and a phone and her tenure file, and she was standing at the gate of a greenhouse in Crete, and the plant was turned toward a neighbor it could not see.
She stood there for a while. The sun came up over the ridge, and the light hit the polycarbonate and turned the greenhouse golden, and Yannis was inside, washing the last cup, and the plant was turned toward its neighbor, and she did not write it down.
She walked down the path to the road, and the plant was behind her, and she did not look back.