This easy indoor hydroponic cannabis grow guide uses common CFL bulbs as grow lights and forgiving coco coir as a growing medium. It’s designed for the beginner as a cheap and easy way to introduce yourself to growing marijuana.
Startup Cost: Around $300 to get started
Maintenance Cost: $50/month
What to expect: Minimum of 4 ounces/plant, up to about 14 ounces/plant.
Recomended for: People who need a few ounces of weed a month and want a super cheap, super easy, “low-maintenance” grow style.
Don’t be fooled just because it’s easy. Even though I was a complete beginner when I started, I ended up getting 6.2 ounces of dried buds off my very first cannabis plant from my very first grow, which I grew using this system!
I still grow this way today and I get an average of 8-14 ounces of dried buds off each plant. I’ve gotten 16 ounces (a pound) from a one plant that was high-yielding strain before (Northern Lights).
This method is not for everyone!
That’s because growing weed with CFLs isn’t the highest yielding method. But it’s super cheap, super easy, and if you just need a few ounces of dried buds a month, it’s the perfect “low-maintenance” way to grow weed.
I think it would be safe to assume that even a beginner can expect to get at least 4 ounces of dried buds if you just follow these instructions. Even if you mess up, you’ll still get at least that.
You will be growing your marijuana plants indoors in a soil-less medium called Coconut Coir (often called coco coir, or even just coir). Coco coir is a natural fiber made from the husk of coconuts that naturally stimulates the roots of plants and is forgiving when growing marijuana.
For feeding (water plus nutrients), you will hand-water them whenever your plants get dry and you will provide them with all the nutrients they need right in their water.
For lights, all you need are some cheap CFL (Compact Florescent Lights) like the ones you get from your local hardware store. These common bulbs don’t use much electricity and don’t produce much heat compared to other grow lights.
Because CFLs have a short light range (8 inch max) theis tutorial works best for growing plants that are kept shorter than 4-5 feet.
That means you will choose either…
You can still get at least a couple of ounces off each plant, even when plants are kept short and you will be able to harvest your crop in only 3-4 months.
This system reduces many of the problems associated with an indoor soil grow, and is also much easier than almost any other hydroponic grow.
It is a great way to learn about how marijuana plants grow and after doing one harvest yourself, I guarantee that you will start getting millions of ideas on how you want to do your next grow.
Pros of Growing Marijuana with CFL Grow LIghts and Coco Coir
- Cheap and easy to start
- Cheap and easy to maintain even for a complete beginner
- Forgiving way to learn how to grow weed
- Perfect for growing 1-2 plants
- Will produce a smokable harvest in 3-4 months
- Get 6-14 ounces/plant (harvest yields depend mostly on two things: how big you grow your plant and the light intensity you provide during the flowering stage)
- High quality bud since the plant is fed hydroponically
- You can use this method even if you have a very small grow space (I once grew a 1.5 foot plant and still harvest 3 ounces of dried and cured buds).
- Can be used with any strain of marijuana, whether it was started with seeds or clones
Cons of Growing Marijuana with CFL Grow LIghts and Coco Coir
- CFL grow lights are not cost effective when growing more than 5 flowering marijuana plants at a time, if you’re growing more than a handful of plants, you’ll probably want to invest in a LED Grow Light or an even brighter marijuana grow light to supplement your light intensity, instead of just getting more CFLs.
- Hand-watering plants is simple, but can be a pain if you have a lot of plants OR very small pots (which need to be watered more often)
- You have to adjust your CFL bulbs 1-2 times a week, as your plants will be rapidly growing into them
- For best results and to be able to harvest 10+ ounces/plant with this method, you will need invest your time to learn how to keep your marijuana plant short with basic marijuana growth control techniques
This is really a perfect way to grow your first harvest because it’s so forgiving and you will really learn an incredible amount about growing by using this method.
I used this technique for my first grow, and even though I made a lot of mistakes, my plants still did great.
What you will need
- Marijuana Seeds or Clones
- High-quality hydroponic nutrients which are designed for marijuana. I recommend Fox Farms Hydroponic Liquid Nutrient trio since that’s what I exclusively used with good results on my first grow. Another good choice is Canna Coco Nutrient A & B which is a two part system made specifically for coco coir. You can usually find these brands of nutrients at any hydroponic store which is usually going to be cheaper than purchasing online if you count the price of shipping.
- Pots to plant your marijuana in. I recommend getting pots that are 2-3 gallons each. Only get 5 gallon pots if you need to be able to go a long time without watering or if you want to grow tall plants.
- Coco coir (and perlite if you’d like) which can be purchased online or at a hydroponic garden store, Sometimes you can find a soilless mix that already has both coco coir and perlite in it.
- CFLs (Compact Florescent Lights). You will need about two 40w(150w incandescent equivalent) CFLs per plant to start. These lights are easily found at the store or online. You can get different wattage bulbs, but I like bulbs close to the 40w range because they are a small, manageable size but still produce a lot of light. By the time your cannabis is flowering, you may need to get more bulbs to fill in any ‘shadowed areas’ up to maybe two or three more lights per plant. It’s optimal to use ‘daylight’ (6500k) colored bulbs for the vegetative stage and ‘soft white’ (2500k) colored bulbs for flowering (though you can use either kind during either stage and your plant will come out fine). I like to use a mix to make sure my plants get a full spectrum of light.
- Enough light sockets for all your lightbulbs (they’re less than $5 apiece at my hardware store, usually they also come with some sort of clip you can use to clip your lights anywhere. You can double-up light bulbs to a socket (more info below) so that you have less total sockets you have to deal with.
- A timer to make your lights go on and off when you want. You can get a cheap one for $5 or spend up to $30 getting a nice digital one You don’t necessarily need one to start if you veg your plants in light 24 hours a day, but you will need to get a timer by the time you start flowering your plant (about a month in) unless you want to turn the lights on and off manually every day. You can buy timers at your hardware store or online.
- pH Control Kit: This contains pH Up and pH Down (to adjust pH of your water) and a simple strip test. Another option for testing pH is a fancy (and more expensive) digital pH tester though my plants did just fine with the strip test that comes in the much cheaper pH Control Kit. All hydroponic stores and some gardening stores with sell pH Control Kids. You will want to adjust your water so it’s around 5.5-6.0 pH when you water your plants. How do I check and adjust the pH of my water?
Estimated Total Cost for Growing Five Plants
- Marijuana Seeds or Clones: Free – $10/plant
- Nutrients: Fox Farms Hydroponic Nutrient Trio (quart) or Canna Coco Nutrient A & B (1 Liter) – $25-$45
- Coco Coir – $25 / big bag
- Perlite (optional) – $10 / bag
- Five 2-gallon pots – $1 – $5 each x 5
- Four 40w CFLs per plant – $7 – $10 each CFL, or $28 – $40 per plant x 5
- Four light sockets per plant at $4 – $7 each or $16 – $28 per plant x 5
- Power timer $5 – $30
- pH Kit – $10 – $30
Total: $290 – $555 in total start-up costs
Ten ounces of bud retail value: You may get even more but a reasonable estimate is a total harvest of two ounces of dried bud from each of the five plants. At $30-$70/ eighth, ten ounces is equal to $2400 – $5600 which is worth 5-10 times the money you need to put in to get started. I got a total 6.2 ounces of dried buds off my first cannabis plant I grew using this system (pictured below in flowering section). I still use this method today and on average I get 3-4 ounces off each cannabis plant.
After your first grow, you will only need to get more plants, more coco coir, and more nutrients which will significantly bring down the start-up costs for subsequent grows.
Remember, you can start out with fewer lights and light sockets(start with 2-3 per plant), and will only need to get more as you notice shadowy patches on your plants that aren’t getting enough light. The great thing about all of the items needed for this technique is they can all be used in future grows, even if you decide not to continue with this method. For example, even if you end up getting HID lights eventually, you will always be able to use the CFLs for starting out new plants, or for adding additional side lights.
A Note about Using CFL Lights
You will need about two 40w(150w incandescent equivalent) CFLs per plant to start. These lights are easily found at the store or online. You can get lower or higher wattage bulbs, but I like bulbs close to the 40w range because they produce a lot of light, but are still a small, manageable size. By the time the plants are flowering, you may need to get more lights per each plant to fill in any ‘shadowed areas’ up to maybe two or three more lights per plant. It’s optimal to use ‘daylight’ (6500k) colored bulbs for the vegetative stage and ‘soft white’ (2500k) colored bulbs for flowering (though you can use either kind during either stage and your plant will come out fine). I like to use a mix to make sure my plants get a full spectrum of light.
I recommend getting some heavy duty clamp light sockets which you can use to power your light bulbs. These light sockets are able to clamp to most anything and they come with a reflector for your lights. When looking for clamp light sockets, avoid anything that’s made of plastic (it’s cheap and will break) and try to find something with at least a 9 foot long cord. You’d be surprised at how annoying it is to try to find a way to make a 6 foot cord work.
To maximize the light your plants are getting, you can use a light socket extender and a twin light socket adapter to fit two lights per each clamp light socket (without the extender, they probably won’t fit). Setting up two lights per socket can often be cheaper than buying an individual light socket for each light, especially if you buy online. It also is really convenient for arranging around your plant.
Click here to learn more about grow lights and the length of time you provide light to your cannabis plants each day.
How to get started
Optionally fill the first couple inches of your pots with perlite for extra drainage, and then fill the rest of the pot with coco coir. Water your pot with coco coir thoroughly until water drains out the bottom before adding your seeds or clones. Set up your lights so that they can start around the height of your pots and eventually be raised to the final height of your plant (2-3 feet depending on your marijuana strain and how long you let you plants stay in the vegetative stage). Once you have everything set up as described, simply add your marijuana seeds or clones and set up your lights so that they’re about 4 inches away to start.
You will want to start feeding your plants with nutrients at quarter strength for the first week, then work your way up to full strength slowly. I recommend following the instructions exactly as provided by the nutrients. For example, if you are using Fox Farms Hydroponic Liquid Nutrient trio, just follow the feeding chart that comes with the bottles and water your plant with nutrients every other watering. When not using nutrients, make sure you still pH your plain water before your feed your marijuana!
You will want to water your marijuana whenever the top of the coco coir starts feeling dry. This will start out with you watering the plants every couple of days, and may end up with you watering them once a day towards the end of the marijuana flowering cycle. You want to ensure that you have about 20-30% extra run-off water come out the bottom of the container every time you water your plants. The reason for this is that coco coir tends to form natural salts if it the fertilizers just sit in there and never get washed out. Making sure you keep adding water until you get run-off is also a great way to make sure that your plants are draining properly. As I said before, make sure to feed your marijuana plant with plain, pH’ed water every other watering. This will greatly help reduce the amount of salt buildup and prevent nutrition problems from occuring. If your marijuana shows signs of drooping, chances are you are over or under-watering. In order to prevent over or under-watering, make sure you water thoroughly every time, and wait to water again until the top inch of coco coir feels dry.
After your plants have grown accustomed to their new environment (after a couple of days for transplanted clones, or when your seeds grow their second set of leaves) then you will want to move your CFLs so that they are about an inch away from the plant. CFLs lose a lot of light the further away they are and their light is almost useless once the plant is 6 inches away. Your biggest task when growing your marijuana will be adjusting the lights. The CFL bulbs should always be as close as possible to the plants, yet they need to be far enough away that your marijuana doesn’t grow into the lights and burn its leaves. If you check on your plants constantly, you can keep the lights closer. If you’re going to be away for a while, you should move the bulbs away to give your marijuana some growing room. Personally for me, adjusting the lights was one of the most fun parts of growing marijuana using this method because it gave me something to do while I was hanging out in my grow room. As a beginner, I always wanted to keep checking in on my marijuana plants all the time, and adjusting the lights gave me something I could do to sastisfy that urge. You may also want to rotate your plants every day in order to provide the most even amount of light from all sides.
Your marijuana can’t get really get too much light from CFLs and the only thing you need to worry about with the CFLs is burning your plants if they get too close. Basically if you put your hand where your plants are closest to the light, and the light feels too hot to be comfortable, then the light is too close. If your hand just feels warm, but not hot, than your plants are at the perfect distance. I generally kept my CFL bulbs 1-2″ from the leaves during the whole grow.
If you notice that your plant is growing with a lot of space between nodes or otherwise seems like it’s ‘stretching’ upwards, that means that it probably needs more light. Try adding an extra CFL or two or move tem closer. If you notice your plant is having any other issues or something doesn’t seem right, check out the Plant Problems and Symptoms Guide.
When your cannabis plants are about half their final desired height, you will change them over to the flowering stage so they start growing buds. By half the final desired height, I mean, if you wanted your plant to achieve a final height of 2 feet, then you would switch your marijuana to flowering when they’re about 1 foot tall, or half of 2 feet. If you wanted your marijuana to grow to be 5 feet tall, then switch them to flowering when they’re at a height of 2.5 feet. The reason for this is that marijuana will generally double in height after being switched over to the flowering stage.
To initiate the flowering stage, you will switch your light schedule so that your lights are on for 12 hours a day, and off for 12 hours a day. During the ‘off’ period, your marijuana should be in total darkness. This light schedule will trick your marijuana into thinking that the days are getting shorter and fall is coming. The 12-12 light schedule will cause your plants to begin the flowering stage and start focusing on making buds instead of just growing. If you don’t change your schedule to 12-12, chances are your marijuana will just keep growing forever and never make buds.
After switching to 12-12, you should start noticing your plant making it’s first sex organs after a week or two. Females will grow white hairs and males will start growing grape-like balls. In order to maximize on the amount of bud you get, you will want to make sure you remove any males so they don’t impregnate you females. If they stay together than your females will get pollinated by the males and will end up making lots of seeds instead of buds. Unless you have a reason to keep males (for example breeding), you probably want to just kill any male plants because they won’t make any usable bud anyway.
When growing with CFLs, it becomes harder and harder to fully illuminate the plants as they get bigger and grow more branches. You will maximize the total amount of buds you get by keeping the plant smaller (and therefore easy to bathe in light), and then harvesting more often since your plants will be ready to harvest much sooner.
As the plants get taller and starte blooming, you may need to get a couple more CFLs to light them from the sides. Basically if you see any dark or shadowy areas that are more than 6 inches from a CFL, then you should get another CFL to plug in that ‘hole.’
Towards the end of the flowering cycle as your marijuana approaches harvest time, you may notice that some of the oldest leaves start turning yellow and falling off. This is totally normal and is a sign that your plant is taking nitrogen out of the leaves and putting them into the buds/flowers.
You will want to stop feeding your marijuana any nutrients for the last two weeks before harvest to ensure the best tasting bud. Simply feed them plenty of water without nutrients for these last two weeks, but make sure you’re still adjusting the pH so they absorb any leftover nutrients in the coco coir. I usually stop feeding my cannabis nutrients and start feeding them water when about 75% of all the pistols (hairs) have turned dark and started curling in towards the buds.
Pleast view the Harvest Section of my general cannabis grow guide for more information about when and how to harvest your plant. This guide should tell you exactly what to look for as far as determining if your cannabis is ready for harvest.
When using this method I’ve found my cannabis to be really resistant to issues or problems, especially considering this method was the one I used for my very first harvest and I had no idea what I was doing when I started. Over the course of my first grow I made several mistakes, including dropping a light on one of my plants and accidentally burning some of the leaves on the lights. Every time something happened to a plant, it seemed to take it in stride and just keep growing. Despite all my mistakes, I still got 6.2 ounces of dried buds off my first plant grown with this grow method!
I really like this technique for a beginning cannabis grower because it’s a really good way to get a feel for how plants grow and how the cannabis plant grows in particular. It can be hard to decide what you want to do for you first grow, and this is a really cheap yet effective way to get started with growing and get good results. After having one successful grow under your belt, I guarantee that the whole process will start making more sense. Even if you end up eventually moving on to other types of growing systems, you will be able to use many of the materials from this system with your future grow.
If you end up using this technique or have any other thoughts or comments I’d love to hear from you!