Momento: All Greenhouse Room Puzzle Solutions (Sundial, Grafting, & Herbicide)

Solving the Momento Greenhouse room puzzles requires creating a hybrid Nocturne Bloom, synthesizing a powerful herbicide, and aligning three Chromatic Lenses on the main sundial to unlock the Arboretum Core. This multi-stage puzzle is one of the game's first major roadblocks, demanding that you explore every corner of the overgrown labs to find the components needed to bypass the intricate security lockdown.

This guide provides the direct solutions to every step. We'll cover the precise locations of all key items, the correct chemical mixing sequence, the plant grafting formula, and the final alignment for the sundial lock. No more backtracking or guesswork.

01

What is the Main Objective in the Greenhouse?tag

The entire Greenhouse section is designed to keep you out of one place: the Arboretum Core. This is where Dr. Aris Thorne conducted his most dangerous experiments, and the door is sealed by a sophisticated system that integrates biological, chemical, and mechanical locks. Your goal is to systematically disable all three layers of security.

To do this, you must solve three major, interlocking puzzles:

1. The Grafting Table: You need to create a unique bioluminescent flower, the Nocturne Bloom, which acts as a biological key.
2. The Chemical Synthesizer: You must mix a potent herbicide, codenamed 'Eradicator,' to dissolve the mutated, hardened vines choking the Core's entrance.
3. The Sundial Lock: The final lock requires three Chromatic Lenses (Red, Green, Blue) to be installed in projectors and aimed at a central sundial, aligning with symbols revealed by the Nocturne Bloom's light.

Attempting these out of order will waste resources. For example, the weak herbicide you can craft early on is insufficient for the main door vines. Follow the steps below for the most efficient path.

02

The Sundial Lock: All 3 Chromatic Lens Locationstag

The central mechanism in the main dome is a large, ornate sundial surrounded by three dormant light projectors. The puzzle only activates once you acquire the lenses and have a way to see the hidden symbols on the dial. Finding the three Chromatic Lenses is a scavenger hunt across the entire Greenhouse sector.

Red Chromatic Lens Locationtag

The Red Lens is the most straightforward to find. It's located in the small, glass-walled observation office overlooking the main dome. The lens sits inside a locked briefcase on the main desk.

• Find the Key: The Office Keycard is not in the office itself. Proceed to the western corridor, past the grafting lab, until you find a collapsed section of catwalk. A deceased researcher's body is slumped against the railing. Interact with the body to retrieve the Office Keycard from their lab coat.
• Unlock the Case: Return to the observation office, use the keycard on the door, and then use your lockpick on the briefcase. The Red Lens is inside.

Green Chromatic Lens Locationtag

The Green Lens is hidden within the Humidification Control room, a small maintenance area accessible from the eastern side of the main dome. The lens itself is inside a wall locker, but the locker is rusted shut and covered in a less aggressive form of fungal growth.

• Craft a Weak Acid: You cannot open this locker by force. You'll need to use the Chemical Synthesizer to craft a Mild Corrosive Agent. The formula is pinned to the bulletin board right next to the synthesizer: 1 part Isopropyl Alcohol + 1 part Acetic Acid. Both reagents are commonly found in the lab and storage areas.
• Dissolve the Lock: Craft the agent and apply it to the rusted locker mechanism. The lock will dissolve, allowing you to open the door and claim the Green Lens.

Blue Chromatic Lens Locationtag

The Blue Lens is held by an enemy. Specifically, it's dropped by a unique variant of the Spore Lurker that patrols the flooded Propagation Basement. This basement is accessible via the service ladder near the Chemical Synthesizer.

• Identify the Target: This specific Spore Lurker is visually distinct; it has a faint, pulsating blue glow in its central mass. It is tougher than the others and has an area-of-effect spore burst attack that causes a visual distortion effect.
• The Strategy: Use fire-based weaponry if you have it, as it is highly effective. Otherwise, keep your distance and aim for the glowing blue center. Once defeated, it will drop the Blue Lens along with other resources. Be sure to pick it up immediately, as items can despawn in the murky water if left for too long.

03

The Grafting Table: Crafting the Nocturne Bloomtag

The Grafting Table in the western botany lab is used to create the Nocturne Bloom. This flower emits a special wavelength of light needed to reveal hidden symbols on the Sundial Lock. You cannot solve the final puzzle without it. To craft it, you need the correct formula and three specific biological components.

Finding the Botanist's Journaltag

The formula is not on a computer or a whiteboard. It's scribbled on a torn page from Dr. Thorne's personal journal. The page is found in the upper-level library, a small, quiet room accessible via the spiral staircase in the main dome. It's being used as a bookmark in a large botany textbook titled 'Anomalous Flora of the Neogene Period' lying open on a reading table. The page details the exact three-step process for a successful graft.

Step-by-Step Grafting Formulatag

With the journal page, you now have the recipe. You must collect the components and combine them at the Grafting Table in the precise order listed. Using the wrong order or wrong components will waste the items and produce a useless, withered plant.

1. Find the Components:
   • Sun-Kissed Fern Root: Located in a planter in the main dome, directly under the brightest section of the glass ceiling. It glows with a faint golden light.
   • Moonpetal Stalk: Found in the dark, cool environment of the Propagation Basement, growing in a patch of moss on the far wall away from the water.
   • Nutrient Solution PX-12: This is a chemical reagent. A single canister can be found on a shelf in the Chemical Storage room, adjacent to the synthesizer.
2. Combine at the Grafting Table:
   • Step 1: Place the Sun-Kissed Fern Root into the central soil reservoir.
   • Step 2: Use the grafting tool to attach the Moonpetal Stalk to the root base.
   • Step 3: Introduce the Nutrient Solution PX-12 into the irrigation port.

The machine will whir to life, and after a few moments, the glowing Nocturne Bloom will emerge. Take it.

04

Putting It All Together: The Final Sequencetag

Once you have the three Chromatic Lenses, the Nocturne Bloom, and have cleared the vines with the Eradicator herbicide (mixed from Perchloric Acid and Glycerol found in the chem storage), you are ready to open the door to the Arboretum Core.

Here is the exact final sequence of actions:

1. Place the Bloom: Approach the small, empty pedestal directly in front of the Sundial Lock. Place the Nocturne Bloom here. Its light will project onto the sundial, revealing three faint symbols: a Crescent Moon, a Full Sun, and an Eclipse.
2. Insert the Lenses: Go to the three light projectors surrounding the sundial. Insert one Chromatic Lens into each one. The order of insertion does not matter.
3. Align the Beams: This is the final step. Each projector can be rotated to aim its colored beam at one of the three symbols. If you try to guess, an alarm will sound and you'll have to reset it at a nearby terminal. The correct alignment is hinted at in Dr. Thorne's notes, linking colors to celestial bodies:
   • Blue Light → Aim at the Crescent Moon symbol.
   • Red Light → Aim at the Full Sun symbol.
   • Green Light → Aim at the Eclipse symbol (representing the Earthly obstruction).

Once all three beams are correctly aligned, the Sundial will click loudly, the rings will retract, and the massive door to the Arboretum Core will grind open, completing the Greenhouse puzzle.

05

Greenhouse Room FAQtag

• What if I can't find the Perchloric Acid for the main door vines? The Perchloric Acid is in a single, specific location: a yellow hazardous materials cabinet in the Chemical Storage room. If you've already explored it and don't have it, check your personal storage box, as you may have picked it up earlier. It is not a random drop.

• Can I miss the Botanist's Journal page permanently? No, the journal page is a critical path item and cannot be missed. The library door remains unlocked, and the book containing the page will always be there until you collect it.

• Does the order of the lenses in the projectors matter? No. You can place the Red, Green, and Blue lenses into any of the three projectors. What matters is which symbol each colored beam is aimed at. Blue must hit the moon, Red the sun, and Green the eclipse, regardless of which projector they are in.

• The Spore Lurker in the basement didn't drop the Blue Lens. What now? This is a rare bug, but it can happen. If the unique blue-glowing Lurker is defeated and does not drop the lens, try reloading your last autosave. The game typically saves upon entering a new major area like the basement. The enemy and its drop should respawn correctly.

The Last Wordtag

The Greenhouse is a masterclass in puzzle design, forcing players to think holistically about their environment rather than tackling disconnected problems. By weaving together botany, chemistry, and environmental exploration, it serves as a crucial test of the skills you'll need for the far more complex challenges waiting inside the Arboretum Core and beyond. Good luck.