Brewing potions always takes a long time; some special ones—like Felix Felicis—are said to simmer for half a year.
With that in mind, Sean planned to use the block right after the first afternoon Transfiguration lesson.
He prepped five sets of ingredients and brought his crystal vials—expensive containers packed in tiny boxes. Because they'd cost seven Galleons total, the shopkeeper at Slug & Jiggers had thoughtfully boxed each vial. The long-bearded old wizard in the shop had claimed the set preserved potions twice as well as ordinary glass.
Sean figured he was bluffing. Books said that if stored properly, a potion wouldn't spoil even in the open air. Ancient wizards even used kettles, and apothecaries back then loved the party trick of pouring different liquids from the same kettle—leaving Muggle nobles chattering in amazement. In truth, that was just a potion degrading under certain conditions (like exposure to light).
As for whether degraded potions cause trouble—just check whether a wanted notice appears at the castle gates the next day.
Afternoon.
A pure-white owl skimmed over Sean's head, hooting and grumbling. Outside, the sun was so warm it felt like it could soak through every first-year. He'd never seen such a brilliant summer; Hogwarts and the moors were glazed in gold. The island was like an oil painting, dotted with a gilded castle.
If only Snape's classroom weren't in the dungeons, he'd feel even better.
This afternoon he felt like a treasure-thieving adventurer: under Snape's watch, he'd try to brew a treasure of his own.
With a head full of plans, he followed a green stone path and pushed open the greenhouse's oak door.
He'd promised to help the professor harvest Puffapods and transplant Bouncing Bulbs into Greenhouse One.
A rich earth-smell filled Greenhouse One; fine droplets beaded on the glass roof and ran down in winding rivulets. Professor Sprout wasn't alone today—she was ringed by students: round-faced Neville, Ernie watering with great care, and a short, pudgy boy Sean didn't know.
Sprout stood beside a crate heaped with fresh manure, gray-brown hair twisted into a tight bun, bright eyes peering shrewdly from under her patch-mended hat.
She clapped the soil from her gloves and came over. "Oh, every year about now the greenhouses welcome new little sprouts. It's a delight…"
She opened Greenhouse One's door. "Come along, Mr. Green. Let's fetch the Bouncing Bulbs—those little rascals have probably grown impatient."
When she spoke, her hat usually bobbed agreeably. Today it didn't. Sean found himself staring at the blackened patches on the hat and thought of Professor Snape's dark, brooding eyes.
Brewing in secret won't break school rules… right? he wondered.
When he came back to himself, he was meeting a steady, kindly gaze.
"My dear Mr. Green—how rare. You were daydreaming?" she teased, without the slightest doubt in her eyes. "Your timing is perfect. Come along—something interesting is waiting for you."
Warm as ever, Professor Sprout led Sean toward another domed house, ignoring his puzzled look.
They stopped before the dome marked with a plaque: "Greenhouse Three."
Sean had never been inside—Michael had said the plants here were more fascinating and more dangerous. Sprout drew a big key from her belt and unlocked the door.
A wave of humid fertilizer air washed over them. A many-tendrilled green plant spread its arms across the space; beside it, green seed-pods like beans were bouncing inside a low fence. Sean recognized the Bouncing Bulbs—but why were they surrounded by Venomous Tentacula? And why wasn't the territorial plant attacking them?
As he studied, Sprout's bright, cheerful voice rose over the rustlings of the greenhouse.
"Oh, Mr. Green—let me tell you a story.
"Bouncing Bulb seeds need to germinate in damp darkness—which, by chance, is exactly where Venomous Tentacula gather. Roughly a third of the bulbs in here live alongside them. The Tentacula won't allow other plants to invade their territory—yet look: the Bouncing Bulbs still thrive…"
Hooking his curiosity, the plump professor continued in a tale-spinner's low cadence:
"If you look closely, you can see the Fanged Geraniums standing nearby. The mutual deterrence between the two creates just the conditions the bulbs need to sprout, break soil—and bounce away. Nature is marvelous. Life finds a way."
She bent gently, eyes warm and sincere.
"Bulbs far from here are always 'safe,' but if they cower forever in some dry, hot corner for fear of Tentacula, letting the pods wither—that, my dear, isn't what life is for."
The story of the bulbs moved him. He looked to the professor; the plump witch gave him a slow, steady nod.
"You'll do fine. Don't be afraid, little one."
…She knew what he meant to do.
By the time Sean stepped back out of the greenhouse, he felt calm and settled, earth-scent clinging to him. He didn't know how she'd guessed, but if she tacitly approved—encouraged him, even—then he couldn't be breaking any major rule. And if he was, it wouldn't be anything serious.
So—
After the afternoon Transfiguration class, under Justin's awed look and Hermione's puzzled one, Sean slipped away down the corridor.
The air grew colder. The wall-lined glass jars came back into view—those shiver-inducing specimens floating in preservative. Sean held his breath and hoped Professor Snape wouldn't be there.
Professors were busy, after all—and Snape, as Head of Slytherin, doubly so.
One glance into the classroom and he let out a long breath. He laid his ingredients out fast, lit the cauldron. The quicker he moved, the more trials he could squeeze in.
He set out his notebook and shorthand quill too. Brewing logs matter: summarizing lessons and iterating is the proper way to learn.
White smoke curled from the cauldron; candlelight slowly took hold in Sean's emerald eyes.