indoor cannabis grow tips

Tips for an Effective Indoor Marijuana Grow

Monday November 28, 2016

O n November 8 th, Maine, California, Nevada and Massachusetts all voted to legalize marijuana for recreational purposes, many of which either include (or will likely include) the ability for residents to cultivate their own cannabis either indoors or out depending on local ordinances.

Though details of cannabis cultivation laws vary by location, we know that California and Massachusetts residents will be allowed to cultivate six plants per person or 12 per household, and that Maine and Nevada residents will likely be able to do so soon as the new laws unfold.

For those living in one of these places with an itchy green thumb, planning a first marijuana grow can be an exciting endeavor. To help the process go smoothly, we’ve developed this guide to growing marijuana indoors.

Starting Your First Cannabis Plants

There are two ways to begin a cannabis grow – either with seeds or clones – and it’s important to consider the benefits and draw-backs of both before beginning the cultivation journey. For example, while clones may reduce cultivation time, seeds are less likely to contaminate a grow area. This is especially important in an indoor environment because it will not contain beneficial insects and other natural pest control options.

Next, consider the best species and strain type to grow. In an indoor grow, space and time restrictions are typically stricter, requiring careful consideration about both species and strain type. For this reason, we recommend beginning with an indica or indica-dominant hybrid which tend to grow shorter, denser and quicker rather than their sativa-dominant counterparts that tend to grow tall, large and take their time to mature.

Lighting Requirements for Growing Marijuana

Each phase of the grow cycle has unique lighting requirements. Seedlings just starting to sprout do best in total darkness until they have reached a height of about two to three centimeters. At this point they can be transferred to a grow medium (if not already) in preparation for the vegetative stage which requires ample light each day – between 13 and 24 hours, in fact.

It is during the vegetative stage that the plant gains the bulk of its mass and will grow more rapidly the more light it receives, though many argue that the plant gains strength during darkness and therefore insist on a 16/8 light cycle during this time.

Once the plants have grown to a sufficient size (which should be about half its final size), it’s time to switch to the flower light cycle: 12 hours of light and 12 hours of complete darkness. When growing outdoors, this happens naturally beginning in late September as the days get shorter, but must be artificially created indoors for any non-auto-flowering cannabis plants.

The light cycle is not the only facet to consider when planning lighting for your cannabis grow. Different grow lights offer different spectrums, intensities and, of course, price tags. Check out our guide for finding the best grow lights for your budget to decide which lighting option is best for you.

Maintaining an Ideal Environment

Lighting is an important part of a successful grow, but can become quite the nuisance when it comes to heat output. Cannabis plants require precise living conditions if they are to produce high-quality cannabis with minimal seeds and excessive temperatures (among other things) can compromise this outcome.

Marijuana plants should be kept between 66 and 76 degrees Fahrenheit, which may fluctuate greatly depending on the location of the grow; plants grown in a basement or garage may experience a more drastic drop in temperature at night when the lights go off so plan your location carefully. Conversely, plants kept under hot lights for long periods may burn or become stressed and produce seeds, making temperature control a pretty big deal.

Though there are some lights you can use to cut down on heat, you’ll often end up reducing the final harvest yield as well. This is one reason ventilation is so important for indoor grows. An easy ventilation system can be installed by pumping heat out of the top of the grow box while replacing it with cool air near the bottom. This will also help control carbon dioxide levels as well as humidity which should be kept between 40 and 70 percent – any less and your plants could dry up and die, any more and they risk developing mildew. A hygrometer can help track the humidity of your grow room.

Nutrients are another important part of a healthy cannabis grow. Like us, marijuana requires a balanced diet to grow to its fullest potential which differs depending on the stage of growth. Plants in a vegetative stage, for example, should receive more nitrogen than phosphorus or potassium because the nitrogen helps promote stem and leaf growth. After switching to the flower cycle, the plants will require more phosphorus to help buds swell, and less nitrogen to discourage long, stringy buds from forming.

Finally, indoor grow areas will need to be kept sanitary to avoid pest infestation. As mentioned earlier, one easy way to do this is to avoid introducing clones (which could be contaminated either from another grow or from the environment during transportation) by starting with seeds instead. You should also clean the grow area thoroughly with a bleach and water solution prior to beginning a grow and always wash hands and remove excess clothing before to entering the area.

If pests do move into your cannabis grow room, you should be able to get rid of them with organic sprays on the underside of the foliage (in the case of an aphid infestation, for example) or by modifying the grow conditions (like letting the top few inches of soil dry out to deter fungus gnats).

There are many resources available to help teach you what you need to know to grow dank weed, but perhaps the best teacher is good ol’ fashioned experience. So read up, plan your supplies and dig in. Your adventure in cannabis cultivation is just beginning.

Do you have any indoor cannabis cultivation tips? Share them with us on Facebook.

Cannabis enthusiasts seeking to set up an effective indoor marijuana grow may use this guide for tips and advice for successful growing operations. From seeds or clones, growing nutrients, lighting, or choosing indica or sativa, PotGuide has you covered.

Top 10 Tips For Growing Cannabis: Answers To Your FAQs

Growing cannabis is a process that requires attention to detail and a significant investment of time, effort, and money. If you want to optimise your resources and maximise your yields, check out the answers to your most frequently asked questions about growing weed below.

  • 1. How important is genetics when growing weed?
  • 2. What is the best cannabis growing medium?
  • 3. Do I need nutrients to grow cannabis?
  • 4. What are the best grow lights for indoor growing?
  • 5. Do I need a fan in my grow tent?
  • 6. How can I achieve the perfect climate for growing cannabis?
  • 7. How often do I have to water my cannabis plants?
  • 8. Will training my plants help me get fatter buds?
  • 9. When is the best time to harvest marijuana buds?
  • 10. Is drying and curing important when growing cannabis?
  • 1. How important is genetics when growing weed?
  • 2. What is the best cannabis growing medium?
  • 3. Do I need nutrients to grow cannabis?
  • 4. What are the best grow lights for indoor growing?
  • 5. Do I need a fan in my grow tent?
  • 6. How can I achieve the perfect climate for growing cannabis?
  • 7. How often do I have to water my cannabis plants?
  • 8. Will training my plants help me get fatter buds?
  • 9. When is the best time to harvest marijuana buds?
  • 10. Is drying and curing important when growing cannabis?

Truth is, while growing weed successfully isn’t necessarily difficult, it is a learning process, and mistakes can, and will, be made. To help you with your grow right from the start, and so you can look forward to a great harvest, here are the answers to 10 frequently asked questions about growing weed.


Genetics plays a significant role in the yield, taste, aroma, and overall growing traits of your plant. Seed selection is therefore a crucial part of the growing process as it will heavily influence the final outcome.

Every grower will have their own preferences when it comes to strains. Some may prefer a powerful, cerebral sativa that leaves them feeling energised and motivated. Others may like a stoney indica or a medicinal strain high in CBD.

The environment where you’re growing is another important factor when choosing cannabis genetics. If you’re growing in a small indoor space, an autoflowering variety can be optimal. Or maybe you’re planning an outdoor grow and want to grow a gigantic cannabis tree. Other factors, such as climate, will also play a role when choosing genetics.


There are many ways to grow cannabis—from sowing seeds in a pot of soil to advanced hydroponic setups. There are different substrates (growing media) you can choose from, including soil, coco coir, and clay pebbles. Some techniques, such as hydroponics, don’t require a substrate at all. Let’s stay with growing in soil for now, as this is what most cultivators use.

What makes a great cannabis soil?

Light texture: Soil should have a light and airy texture. This way, roots can grow effortlessly with easy access to oxygen.

Water drainage: Water should drain well, as cannabis doesn’t like to have “wet feet” for long.

Water retention: Water draining too fast from the pot isn’t optimal either. The soil should be able to hold water (and nutrients) for a reasonable period.

Optimal pH: The pH level of your soil should be about 6.0. A little above or below (5.8–6.3) is okay, but if the pH is way off, your yield will suffer.

Nutrients: Soil made specifically for growing cannabis should already contain nutrients. Most store-bought soils contain enough nutrients for 3–4 weeks of growth.

If you’re new to growing, the best option is to source a ready-made cannabis substrate from a reputable brand. These already have the right structure and contain enough nutrients to get a grow going.

• Pro tip: If you want to grow organically, you can make your own super soil. Organic material such as compost or bat guano can support the growth of beneficial microbes that will produce nutrients for your plants. This way, you won’t need to give additional nutrients; you’ll only need to water your plants. Mother Nature will take care of everything else and reward you with juicy buds with a natural flavour.


Unless you’re an experienced grower setting up a purely organic grow (see the previous point), the answer is: Yes, you will (likely) need cannabis nutrients. But don’t just go crazy, as many fatal mistakes can be made if you’re not careful.

More nutrients doesn’t mean more buds. Overfeeding can easily happen, and indeed it is one of the most common mistakes. Seedlings and very young plants don’t need nutrients at all. If you’re growing autoflowers, they will also need less nutrients than photoperiod plants.

If you’re getting soil from a store, chances are it’s already pre-fertilised: These nutrients normally last 3–4 weeks, which is also the average duration of the vegetative phase. Spoken differently, with good soil, you will likely not need to give nutrients until the flowering phase begins.

Have a question or two about growing cannabis that you need to sort out? Click here for answers to your frequently asked questions, and tips from pro growers.