Botany Manor

To grow the Nightfall, follow these steps:

1. Fill a pot with soil
2. Add a Nightfall seed
3. Water the seed
4. Take the seedling to the attic and place it in front of the projector
5. Add the following coloured plates in order from left to right: Blue, Yellow, Orange, and Red
6. Activate the projector by pressing the switch

As there is other guides before this please see them first.

Chapter 4
You will find this plant in chapter 4 in the hidden room but will grow it much later on in the chapter after reaching the attic

1.Fill pot with soil
2.Add Nightfall seed
3.Add water
4.Take plant to up to the attic and place in spot in front of the projector
5.Add the coloured slides to the projector in order from left to right:
Blue - Yellow - Orange - Red
6.Turn on the projector and the plant will grow

If you need more help with this you can see my video below:

Chapter 4

To grow Nightfall: Fill the pot with soil, add the seed, and water it. Place the pot in front of the light projector in the attic. Take the slides from the box next to it and place them into the light projector in this order then turn it on:
Blue - Yellow - Orange - Red

Full video walkthrough including all achievements, puzzle solutions, and collectible locations! (Timestamps in YouTube Description)