8 Top Tips for Setting Up an Indoor Grow Room

If you have never grown cannabis indoors and are thinking about setting up your first grow room, there are several factors to consider. Becoming an indoor grower takes more than sticking a grow light in a spare wardrobe or attic space, so in this article, I provide 8 top tips to help you hit the ground running.

Table of Contents

• Tip #1: Smell Proof Is Key
• Tip #2: Light Breaks
• Tip #3: Allow Room to Work Inside
• Tip #4: A Digital Hygrometer
• Tip #5: Oscillating Fans
• Tip #6: Keep a Clean Grow Room
• Tip 7#: Light Intensity
• Tip #8 – Air Tight Fittings

Tip #1: Smell Proof Is Key

When you grow loud and pungent cannabis plants indoors, making sure that your indoor grow space does not stink the entire street out will keep your grow room discreet and secure. Your neighbours will also be happy. As long as you invest in a good-quality carbon filter with an airtight connection, you will eliminate the concern of the authorities knocking on your door.

My tip is to spend money on a good brand and ensure your carbon filter size is large enough to ventilate the grow space, recycle the hot air, and replace it with carbon-scrubbed fresh air.

Tip #2: Light Breaks

If you prefer the easy and practical choice of setting up an indoor grow tent, double-check that there are no light breaks. This means ensuring no external light sources cause light to enter your grow space when the plants are in darkness.

This is especially important once timers have been switched to 12/12 and flowering has been induced. Light leakage can confuse plants and lead to lower yields, hermaphroditism, or even failed crops due to light stress, as recommended by Royal Queen Seeds.

Tip #3: Allow Room to Work Inside

Even though filling your grow room from wall to wall and growing the biggest plants possible can be tempting, try to leave yourself enough space to move around inside. This is particularly important in an emergency when you need to get close to your plants.

My tip is to create an aisle in the grow room and space around the sides and edges to facilitate watering and daily maintenance. Avoid overcrowded grow rooms and plan for equipment such as wall fans and oscillating fans, as well as the ability to clean up and sweep.

Tip #4: A Digital Hygrometer

Knowing the temperature and humidity of your indoor grow room will pay off massively and allow you to dial in the perfect environmental settings during the seedling, vegetative and flowering stages. You should aim for a temperature of 75 degrees Fahrenheit and 65 – 70% humidity during 18/6 and 72 – 75 degrees Fahrenheit during the flowering stage with a humidity between 40 – 50%.

My tip is to use a digital hygrometer and sensor that can be placed and left inside the grow room. A good-quality hydrometer will tell you the lowest and highest temperature and humidity levels over 24 hours.

Tip #5: Oscillating Fans

Using fans inside your grow room will allow the plants to stay cool and fresh and grow stronger. Oscillating fans are an excellent way to circulate the air inside a growing space consistently and help create an ideal indoor growing environment. Depending on the size of your grow room, you can use a small 6-inch fan or choose to work with much larger fans.

My tip is to use two oscillating fans inside a grow space, turning at different times to provide the best air flow rate. I always keep my fans at various heights, so I will keep one on the floor and a second two to three feet off the ground.

Tip #6: Keep a Clean Grow Room

A great habit to adopt as an indoor grower is keeping your grow room as clean and tidy as possible. Having a dustpan and brush or a sweeping broom close by and using it daily will help.

My tip is to sweep up any soil or debris that lands on the grow room floor, wipe down the walls and sides of your tents if you notice any stains, and be prepared to bleach and thoroughly clean the room between harvests.

Tip 7#: Light Intensity

The grow light you choose will make or break your indoor grow. Cannabis plants require intense lighting to grow into big, healthy, and productive plants. PPFD directly impacts how well your plants grow. It’s a measurement that helps you understand the amount of light they can convert into energy, which is what they use to build those big, beautiful buds, according to Auto-Seeds.

My tip is to research grow lights and check the manufacturer’s P.A.R. (photoactive radiation) and PPFD levels. Knowing how much light intensity your plants will receive will allow you to calculate how many plants you can grow in your grow space and if you need more or fewer grow lights than you initially anticipated.

Tip #8 – Air Tight Fittings

When you are setting up your extractor fan, carbon filter, intake fan, and aluminium ducting, make sure that your equipment has an airtight seal. The best way to do so is to use thick ducting tape or metal clips to firmly seal everything.

My tip is to double-check that all your ducting feels tight when tugged on, and there are no loose fittings or anywhere that airflow and pressure can escape. Be careful not to pierce the side of your ducting if using metal hooks to hang your equipment to guarantee the extractor is working as efficiently as possible at ventilating air and to reduce the risk of poor airflow, which can lead to powdery mildew and botrytis.

Feature photo: A large-sized flowering room. Photo credit: Bill Sutherland.