How to Set Up a Cheap Grow Room

Want to set up a grow room but don’t have a big budget? Don’t worry. You can set up a cheap grow room and grow yourself some healthy potent weed without having to spend hundreds of pounds, euros or dollars (or whatever currency you’re working in).

Setting up a cheap grow room – what do you actually need?

Firstly you need to set up the enclosed grow room or grow box itself. Then you need to install the right equipment.

The grow room or grow box itself needs to be:


The grow room has to be lightproof – so no light (or very little) can get in or out. Proper light and proper darkness are both crucial for the healthy development of your plants. During the vegetative phase, plants need to be getting 18 hours of light and 6 of darkness, while during the flowering phase it needs to be 12 and 12. Importantly, during the flowering phase, if the plant gets any light at all during its 12 hours of darkness then it might stop flowering and switch back to its vegetative phase.

Have fresh air

Since your cannabis plants will be using up carbon dioxide as they photosynthesise, it’s important there’s a source of fresh air in your grow room. Otherwise, the plants can use up the available carbon dioxide which will then slow down their growth. Even if you just have a hole in your grow room to let fresh air in, that should work, or you can create a duct from the grow room to a source of fresh air. If you’re literally using a room then an open window may be enough.

An air extraction system

Since most grow lights generate a lot of heat, you need to be able to remove the hot air and so an air extractor will help with this. If you use an air extractor with a filter then this will also stop the smell escaping.

Reflective walls

The more the walls of your grow room reflect light, the more light your plants will get and the greater will be their yield. Reflective walls increase the efficiency of your lighting – i.e., the same bulb will yield greater overall light if the walls are reflective. White reflects light and black absorbs it, but even better than white walls is tin foil (aluminum foil) or some other highly reflective material. Obviously tin foil is quite cheap as is white glossy paint so they’re good options.

cheap grow room

You then need to install the following:

A fan

You’ll want to run a rotating fan in order to distribute the fresh air coming in throughout the plants, to make sure they’re all getting enough carbon dioxide. A fan will also help keep the temperature even throughout the room and help stop mould developing. You want the fan to be one that oscillates from side to side so it’s not just always blowing on one area, potentially giving those plants windburn.

Good plant trays or waterproof flooring

Make sure your plant pots are on wide sturdy trays to catch any water spillage and collect moisture from the plants. It’s also a good idea to lay down an old cloth or painter’s dropsheet or something to soak up any moisture so as to not damage the floor beneath.

If you can make the whole floor waterproof, then you can actually spray the floor with water to increase the humidity for the plants. Depending on the size of your grow room, you might be able to do this with large sheets of tin foil, or a waterproof tarpaulin.

Handy water source

Since your plants will need regular watering, you might want to consider running a hose into the room, especially if you have quite a lot of plants. Just make sure the water’s not rushing out at too high a pressure that could damage the plants.

Grow lights

Decent lighting which will give your plants enough light (and heat) to grow to their full potential. Obviously, grow lighting is a big issue in cannabis growing and there are many different kinds of lights, and points of view as to which are best.

You can read a bit more about lighting here: Best lighting for indoor cannabis growing

Generally it’s accepted now that LED lights are the most effective and efficient so they can work out cheaper in the long run. But they are more expensive in the short term. A decent CFL light will do the job fine and they can be had for as little as £20 / £30: CFL lights on Amazon UK

A few tools

While you don’t strictly need anything else, a few tools can be handy to ensure your grow goes well. For example, Seedsman recommend using pH meters to ensure your soil is at the right acidity, and a hygrometer to monitor humidity (to make sure it doesn’t get too high).


How to set up a cheap grow room – how cheap can you go?

What do you actually need to set up a cheap grow room? At its most basic, you just need a good light, containers, soil, a fan, and a cabinet lined with tin foil. In fact, I Love Growing Marijuana estimate that you could set one up like this for as little as $70 / £55 / €60:

  • a cabinet lined with tin foil (free if you already have a cabinet or box you can adapt)
  • some 3 gallon containers
  • a bag of soil
  • a fan
  • a CFL light – these can cost as little as $30 / £20 – click here to browse CFL lights on Amazon UK


How to set up a cheap grow room: references