Saturday August 29, 2020
By Paul Barach
As many cannabis fans find themselves at home longer and longer, there’s plenty of time to think about picking up a new hobby. Maybe it’s finally time to tackle learning Spanish or Mandarin. Perhaps it’s time to get more into baking and see why everyone went so nuts over sourdough. Or it could be time to get into some indoor gardening and see how green your thumb is with a couple of cannabis plants.
The reasons for growing your own cannabis are numerous. There’s the price, the fun of seeing how your favorite plant develops, and the sense of satisfaction as you consume cannabis flower that you cultivated and harvested with your own two hands. As you’re looking around your available grow space with visions of blooming buds dancing before your eyes, there is one question that you should be considering: “How far away should I space my plants?”
Key Factors for Plant Spacing and Setting up a Grow Room
There are a couple of major factors that you need to consider when it comes to plant spacing – as well as growing in general – which we will delve into below.
What is the size of the grow space that you’re working with? Depending on the cannabis strain that you’re planning to plant and raise, the space you’ll need per plant could be anywhere from one to three square feet. This of course all depends on the set up of your lighting, your ventilation, and your pots, but we’ll cover that below.
The main thing you want to avoid is overcrowding. Your plants will branch out towards each other as they grow trying to reach their friends (or hog all the available light). When those branches start rubbing their leaves together they become especially humid and lose their ability to transpire efficiently. This can spread mold among your plants, as well as thrips, spider mites, and other problems. This can become especially problematic when combined with insufficient humidity and temperature controls as well as poor ventilation or air flow.
When considering your available space and planning out how many plants you’re looking to grow at one time, keep in mind that generally you want at least a six inches to a foot of room between the branches. Your actual spacing will vary, but this guideline gives the plants plenty of distance apart and gives you room to maneuver as you care for and harvest your little cannabis friends. You can space your plants closer than this, as long as they are not touching, but at least half a foot is a good rule of thumb.
Grow Containers and Pots
As a general rule, the larger the grow container, the larger your plant will become. While you’ll start with ½ liter pots for any seedlings, you’ll need to figure out the average plant height of the strain you’re growing in order to decide on which pot to use from there. This of course will also vary if you’re growing a shorter, bushier indica or a taller, thinner sativa.
If you’re only looking to grow a shorter plant that maxes out at two feet, you’ll need about a gallon sized pot. If you’re growing anything larger than that, you’ll need to start with a two to five gallon pot. As a pro-tip, while circular pots are more widely used and widely available (especially if you’re looking at a paint bucket set up), square pots will help you conserve space.
Your lighting set up will also have a big impact on your spacing, since your goal is to get as much of that artificial sun on every part of your plants as possible. The first thing to watch out for with your grow room lighting is what type of reflectors or hoods are on the appliance. If the hood is at too narrow of an angle, the bulbs are too deep set in the frame, or the reflective material is cheap, you’re losing a lot of available light while simultaneously wasting a lot of energy.
What you’re aiming for with the right reflector or hood is a range of 16 to 22 square feet of well-lit space per 1000-watt bulb. If you’re using a high quality, double ended bulb, you can get over a third more light intensity than a conventional HID bulb, but you’ll need to hang them higher due to the excess heat. With a quality double-ended bulb you can get a maximum of 27 square feet of usable lighting space.
If you’ve done your plant spacing correctly, there should be enough direct light shining through the canopy to illuminate most of the plant’s leaves.
The light should be able to shine through from the top to the bottom of each cannabis plant’s perimeter, as well as on all sides. If a majority of the plant is being shaded, it will harm the plant’s development. This will lead to less potent trichomes and less buds being grown overall, and can stunt your plant’s growth or leave it vulnerable to disease. If you find some of your plants are stuck in the shade, it’s time to separate your plants even further from each other.
Air Flow and Ventilation
For every 1000 watt bulb, you should also have at least one foot-tall oscillating fan to increase airflow. You should see a slight breeze that moves the leaves and branches on all parts of your plants, from the crown to the base. If there are some plants stuck in an area of stagnant air, you’ll need to move your plants further apart. Still air hanging above or around your plants can harm them by making the leaves too humid.
Every Plant is Different and Needs Attention
There’s no real hard and fast equation on how far you should keep your plants. Each plant is shaped differently, each strain has its own needs, and each room that you grow in comes with its own dimensions. However, making sure that your plants are far enough apart so that they don’t touch is the point to start from when it comes to home growing.
Once your plants are distanced, then it’s time to look at the other important factors mentioned above. Buy grow containers that will fit your room, adjust your plants so that they’re getting enough light on all sides, and be sure that there is enough room for a gentle but steady airflow throughout each plant from top to bottom. Once you meet all these requirements to keep every cannabis plant in your grow happy and healthy, that is your ideal distance to space your plants.
Do you have any tips for new growers looking to start their first round of plants? Share them in the comments below.