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Everything you need to start a grow room

There comes a time in most cannabis lovers lives where we think about where the bud we love so much comes from, and what it would be like to grow our own. For some, it is a conscious decision to make sure that they know exactly what goes into their bud and thus into their bodies, for others, it’s for the pure enjoyment of taking their cannabis hobby to the next stage. Cultivation is certainly a guaranteed way to have a hands-on learning experience when getting to know this incredible, versatile, and rewarding plant. 

With so many different seed varieties on the market – why would you not want to?

It’s pretty easy in the late spring to put a seed in a pot outside and let nature do its thing, with you just making sure to water and feed it often enough. You can end up with some very enjoyable flowers – the only issue here is you have to wait until the summer ends, which of course only comes around once a year. Growing on your window sill can be fun, but really isn’t likely to get you more than a few smokes, at most, because the sun won’t give your plant enough power to produce much when it’s coming through the double glazing. So how do we go about growing some of that sweet high-grade indoors?


Firstly let’s take into consideration the time it will take. The flowering period of cannabis is usually from 8-12 weeks. That’s already 2-3 months! Then you have the vegging time which can be from 4 weeks upwards depending on how big you want your plants. So if you are going to grow, make sure you have 3-4 months where you are going to be in the same place and able to tend to your plants in a way that wont let them suffer. Growing indoors is a similar kind of dedication to keeping a tropical aquarium tank. 

When thinking about growing something indoors that naturally belongs outside you have to consider replicating nature to ensure that firstly your plants survive and secondly – it’s suitable to produce some really good end product. 

Here is a list of the equipment and why you will need to buy them to get started:


This is a sealed space to contain and control your growing environment and they  come lined in reflective material. There are a great number of sizes available, from something that would fit under a table to something that will go on top of one. Then you have something that will sit in the corner and others that take up a whole room. Tents can be better than using a whole room because they have purpose built holes in them for ventilation and allow you to pack down a room, if you are renting an apartment and have an inspection, or move where you are living without much hassle. 

Extractor Fan

This is necessary for exchanging the fresh/waste air in the grow space and helping control the smell, temperature and humidity. 

Complete extraction kits are available online. It is important to match the correct size carbon filter for your fan and to get the right size ducting. You’ll need tape and possibly some cable ties or another set of pulleys to secure it. A fan on the outside of the tent reduces heat inside the tent.

Carbon Filter

This is absolutely essential to remove the smell – it’s nice to be a good neighbour. You will want to replace it every year to 18 months to make sure you are not leaking out any sweet hums of weed. You can also replace the carbon inside to avoid throwing away the whole unit.

Reflector/Light Hood

Having an even spread of light to reach every corner of your tent so your plants are happy is an important factor. There are a lot of different styles. If you don’t have heat issues then a standard adjustable reflector works just fine, but if you have heat issues to deal with, enclosed hoods that hook into your extraction system are probably what you need. I recommend purchasing the clicking adjustable pulleys to hang the lights on which makes altering the height as the plants grow so much easier.  


Having the right power bulb for the space you are using and the right spectrum light for the photoperiod the plants are on will make all the difference to your growing experience and the bud you finish growing. High Pressure Sodium (HPS), Metal Halide (MH), Ceramic Metal Halide (CMH), Compact Fluorescent (CFL) and Light Emitting Diodes (LED) are all suitable options and available in different light spectrums for different times of the grow cycle. 


This is the power brick that converts the voltage from the mains power to what the bulb needs to emit the right light spectrum. Analogue ones are pretty cheap these days but there are a growing range of digital ballasts to choose from, some of which you can vary the power output on. 

Oscillating Fan

Perfect for helping to move the air around the tent/room so it doesn’t stagnate or create any damp spots. When the plants have this it also helps strengthen the stems and branches. 

Oscillating fan in a tent week 2 in flower

Humidity/Temperature Controller

If you are not able to check your garden frequently throughout the day and you have changes or swings in temperature and humidity at night these devices can be real stress relievers. They allow you to plug in a heater, fan, humidifier or dehumidifier and set the temperature/humidity parameters for them to turn on and off automatically when needed. It is important to note that as your plants change size the humidity levels change too so it is important to monitor this through your first few grows. The time of the year and outside temperature can affect your humidity levels from one day to the next. 

An example of a dual controller is the Inkbird range who have a number of temperature humidity controller options. This one sadly is not available anymore but very similar or updated ones are for sale. 


This is used to help increase the air moisture level. If there isn’t enough moisture in the air the plants will lose water quicker than they can drink it and dry out. If the air is too dry it will also make the soil dry out quicker.

Humidity being pumped into a 1.2m grow tent that naturally sits at 30% RH. A small 5l humidifier is enough to keep this at 50-60% humidity for 24-48 hours. 


Too much moisture in the air can cause your plants to get bud rot and become useless. Getting an unexpected patch of rain towards the end of flowering could ruin everything just from an extra 10% humidity. For this reason it is always good to have a dehumidifier in your grow space. 


Plants cant grow when temperatures drop too low, the winter and night time can be too cold for your plants and they could get root shock. Small oil heaters, greenhouse heaters or even electric mattress topper heaters can be effective in an enclosed space to stop the roots from getting too cold. You don’t want them to go below 18 degrees or they will shock and stunt growth. 

Surge Protector(s)/ Extension Cable

You will have a number of plugs to plug in with varying watts and voltages so using surge protectors is a safety precaution you should try not to skip over on. Fire and wire safety is paramount. 


To get your plants to flower you need to change the length of time the light is on. These are available in analogue and digital. 

Training Net/Stakes

Plants can sometimes produce flowers and colas that are too heavy for their own branches. To make sure they don’t fall over and break there are nets you can use that stretch over the grow space and give support to the plants structure – you’ll want this in place before they get too big though. You can also use traditional stakes and ties on any at risk branches as you see them if you don’t use a net. 


You will need these to grow in. Traditional plastic pots work great but there are also a number of pots that encourage vigorous root growth,such as the felt pots which are also easily washable. 


Sitting your plants on trays stops your tent floor from getting unnecessarily messy and risking any leaks from run off. It can also stop the soil in the pots from drying out. 

Spray Bottle

Foliar feeding your plants and replicating dew at the star of their light cycle is a good way to keep them healthy. A standard trigger spray works well but a pump pressure one makes the job much easier. 


You will need an adequate size vessel to mix up your plant food in. As your plants grow they will require a greater amount of water so get something that will be big enough to make as much as you need in – there is nothing worse than having to mix up the food several times if you are brewing an oxygen tea.

Watering Can

Some people are perfectly happy using a cup but using a rose end to sprinkle the water on can make sure that the medium is spread evenly and doesn’t run down any cracks in dry soil if you have let it over dry. Hollow Broom Handle – if you have plants at the back of the tent that are hard to reach a watering can is easy to pour down a hollow broom handle into the pot as an extension of the spout. This can save a lot of back ache!

Air Pump & Oxygen Stone

Your soil loves aerobic microbes and your plants’ roots love oxygen so oxygenating your water before your plants get it can allow the microbial life in the food to increase leading to healthier soil and giving the roots the o2 they require. When adding oxygen to a food mix it is often referred to as “brewing a tea”. 

RO Filter – Not Essential

If you live in an area with hard water you may find you have issues growing or getting some deficiencies. Using a reverse osmosis filter to purify the water and strip it of all nutrients and minerals allows you to start from scratch and totally control what goes into your plants. You will absolutely need to replace calcium, magnesium and silica without fail though or you will run into problems quickly. These issues can be rectified easily with organic compounds readily available. 


There are a number of different soils available in most grow shops and garden centers which are suitable for growing and will have enough life in them for the first 4 – 6 weeks so you just have to feed them water. It needs good drainage and aeration. Woody/barky soils are not desirable as they dry out too fast. There are now soils available on the market that have been designed from scratch specifically for cannabis that you can just feed water and a few microbial teas throughout the cycle which mean you do not have to use any bottle bought nutrients. 

Soil being made by @living_organics who make a “soil for life” mix that you just water and feed teas crop after crop.


If you are using plant food to make sure you have a bountiful crop the chances are you will use a number of different products. Most feed is made for either the veg or bloom cycle which requires you to change when you switch to the 12 hours of flowering time. The three main compounds that your plant needs are Nitrogen (N) Potassium (P) and Phosphate (K). Veg feed will have higher N levels and bloom will have higher P and K levels. Calcium (C) and Magnesium (M) are also essential but often the water and soil has enough of this in not to have to add it too often. There is almost an endless list of macro and micro nutrients that cannabis plants require to do their best, boost their immune systems and increase terpene production so please keep following the Seedsman grow blogs to keep learning more. Things like food waste compost and earthworm castings can really boost the life of soil that is lacking and are relatively cheap or easy to make at home. 

Dustpan and Brush

It’s good to keep a clean and tidy space. The messier a grow space is, the higher the chance of pest or mould contaminations there will be putting your plants at risk. 


For mopping up any accidental spills – it’s good to have one on hand just in case. 

Final points

Right…that’s everything you will not only need to get started but things you will want to consider getting along the way of your home growing journey in order to grow successfully. 

Depending on the size of your grow space, and if you decide to buy either budget or branded equipment, you will be looking at a setup cost between £350 – £1000. That is about the same as spending £20 a week for a year on bud someone else has grown.

In our follow up blog we will be discussing creating the right indoor growing environment, which will go into detail about why some of the above may be very useful and will help you go from growing pretty good cannabis to growing really excellent grade cannabis. 

Cultivation information, and media is given for those of our clients who live in countries where cannabis cultivation is decriminalised or legal, or to those that operate within a licensed model. We encourage all readers to be aware of their local laws and to ensure they do not break them.

This post is also available in: French


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