How to Easily Grow Marijuana Hydroponically
Whether you call it weed, cannabis, pot, marijuana, or something else, the plant known as Cannabis Sativa is actually easy to grow at home when you know what you need to do. Growing hydroponically will provide you with higher yields and a shorter grow time compared to growing in soil, but it can often be difficult for the beginning grower to get started with hydroponics. However, most people think of plants growing in water when they think ‘hydroponics’ but actually your plants will get many of the benefits of hydroponics as long as they’re getting their nutrients directly in their water supply. However because of superior air to water ratio in hydroponics, it remains the industry standard
This tutorial will show you step-by-step how to grow your marijuana in 3-4 months using the (arguably) easiest hydroponic method: hand-watering in a soil-less medium. This grow system is designed for the beginner as an easy introductory method to grow marijuana which is low in both cost and effort, while still producing 1-3 ounces of dried buds per plant. All the items needed can be purchased at either a hardware store, online, or at your local hydroponic shop for under $300 for up to five plants. If you’re growing less plants, your costs will be even less.
Obtain all the needed items. If you’re careful to shop around, you should be able to get everything you need for five plants for $300-$500. You should expect to get 1-3 ounces off each plant at the end.
Set up your grow lights. They should start out a little higher than the height of your pots, and should have room to be raised to the final height of your plants. There are a million ways to set up or hang the lights and you will need to do what works for your grow area. The simplest method is to either hang them from the bar in your closet or you can also clamp the lights onto something nearby that is the right height.
Start feeding your plants with water(filtered or tap) mixed with nutrients and adjusted to have a pH of 5.5-6.0. In the beginning, give your plants nutrients at quarter strength and work your way up to full strength nutrients over the course of a week or two. One of the biggest mistakes many new growers make is giving their plant too many nutrients which can hurt your plant. Most brands of nutrients will come with a hydroponic feeding schedule which can usually be followed exactly. You can get Fox Farms Hydroponic Nutrient Trio and follow their included instructions exactly if you’re not sure what to get for nutrients. The Fox Farms Hydroponic Nutrient Trio works great for growing marijuana. After you have added your nutrients to your water, you’ll want to adjust the pH of the solution to around 5.5-6.0 to ensure proper nutrient absorption.
Water your plants with pH’ed and nutrient-filled water whenever the top of the coco coir starts feeling dry. This will start out with you watering the plants every couple of days when they’re small, and may end up with you watering them once a day towards the end of the plant’s flowering cycle. Ensure that at least a little extra run-off water comes out the bottom of the container whenever you water your plants to ensure that unused nutrients don’t build up in your medium. Coco coir and perlite are very forgiving if you accidentally over or under-water your plant, but make sure to adjust your watering schedule accordingly if you notice your plant’s leaves are wilting or drooping.
Keep your marijuana plants in the Vegetative Stage of growth until they are about half their final desired height by giving them 18-24 hours of light a day. Your marijuana has two major grow phases after it’s a seedling, the vegetative and flowering stages. You will treat the plant differently depending on what stage it’s in. During the vegetative stage, your marijuana plants are only worried about growing and getting big. In order to keep your plants in the vegetative stage, they will need to get at least 18 hours of light a day. This simulates ‘summer’ when the days are long. You can give your plants as much as 24 hours of light per day during the vegetative stage, but you’ll find success as long as you stay within that 18-24 hours or light per day range.
The height of the plant is often the main factor when determining how long to keep your marijuana plants in the vegetative stage. Your plant can double its height in the flowering stage, so you will want to keep the plant in the vegetative stage until it’s about half it’s desired final height. If growing in a closet, it’s a good idea to keep your plants in the vegetative stage until they’re 6-18″ tall.
When they’ve achieved the correct height, tell your cannabis plants to begin the Flowering Stage of their life so that they start producing buds by changing to a 12/12 light schedule. In the flowering stage, your plants stop worrying about growing as much, and start putting their energy into growing flowers/buds. You will need to tell your plants when it’s time to start flowering. In the wild, marijuana plants start flowering when the days start getting shorter because that’s a sign that winter is coming. In order to simulate the same conditions, you will need to switch your light schedule so that your lights are on for 12 hours a day, and off for 12 hours a day.
Determine the gender of your plants 1-2 weeks after first changing the lights for the flowering stage and get rid of any males. After making the switch in light schedule, you will start noticing the first signs of your plant’s gender about 1-2 weeks. Female plants will grow white hairs and males will start growing grape-like balls that eventually become pollen sacs. In order to maximize on the amount of bud you get, you will want to make sure you remove any male plants so they don’t pollinate your females. If male and female plants stay together, than your females will end up making lots of seeds instead of buds. You also don’t get any usable bud off of a male plant, only pollen. 
Wait patiently while your plants mature in the flowering stage. This is often the toughest part for beginning growers. The Flowering Stage can last from 6 weeks to 12 weeks or longer depending on the marijuana strain that you’re growing with. 
Start feeding your marijuana plants just plain, pH’ed water 1-2 weeks before it’s time to harvest. Otherwise you may actually be able to taste the nutrients in your final buds(has a chemical after-taste). Towards the end of your plant’s flowering cycle, 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. This is a signal that it’s getting close to harvest time, and you’ll usually want to stop giving your plants nutrients with their water for the last 1-2 weeks to ensure the best possible taste of your final bud.
Harvest your plants (when they’re ready) by cutting down the whole plant or cutting off pieces of buds at a time. There are many methods to determine the right time to harvest your plant. Basically, you want to harvest when 50-75% of the white pistils/hairs have turned amber/brown. Another way to tell is when the trichomes (also known as crystals or resin glands) are either all white/milky or half white and half amber. Harvesting earlier will give a more thoughtful or in-your-head marijuana experience while harvesting later will give you a heavier or more relaxing marijuana experience. You will want to experiment to find what harvest time is the best for you.
Trim your plant so that there aren’t any leaves sticking out from the buds. Leaves will make your final smoke a lot more harsh and don’t contain much THC, so you don’t want them in your final product. You can still use them to make hash, butter, or Green Dragon.
Hang your trimmed buds upside down in a cool, dark place and let them dry until the buds snap off cleanly (as opposed to just bending) when you put pressure on them.
Place the buds in an air-tight container and leave them in a cool, dark place for 2 weeks to a month of more to ‘cure’ your buds. Open the jar once a day to get some air ventilation and make sure you release any moisture. Moisture is your enemy when curing and will cause mold, so make sure your buds are properly dried before curing them.
There are many benefits to growing your marijuana plants indoors in a soil-less medium that is a mixture of Coconut Coir(also known as coco coir) and perlite (provides great aeration and drainage). Neither medium attracts bugs, and because your plants roots get access to superior amounts of both oxygen and water, your plants will grow much faster and get higher yields than if they were grown in soil. Plants also get higher yields and grow faster when they get their nutrients out of their water (hydroponically) instead of seeking it out from the soil.
If you notice that just the tips of your leaves start turning yellow or brown, then your plant is showing the first signs on nutrient burn (too much nutrients). If this happens, feed the plants with half-strength nutrients for a week or so then slowly go back to normal. Some strains of marijuana can soak up a lot of nutrients, while certain others are prone to nutrient burn. A plant can also show signs of nutrient burn if you don’t maintain the right pH, so make sure to always pH your water!
As the plants get taller and start blooming, you may need to get a couple more CFLs to light them from the sides. Basically, if you see a shadowy spot, then your plant would benefit from an extra light there.
Most new growers tend to harvest their plants too early because of excitement. Your buds will gain about 25% of their final size in the last 2 weeks, so it’s important to try to be patient and wait until the right time. Buds that are harvested to early are also often too ‘edgy’ for some people. As the buds develop, they start producing chemicals which tend to be more relaxing and ‘stonier’. Many people like to cut off only a few pieces of their plant at a time and let the rest of the plant keep growing. This will allow you to test out the bud at different stages. .
In most places you can purchase seeds online which will get shipped to your door. However, it’s up to you to determine whether it’s legal or not for you to grow marijuana where you live. These days, many places are decriminalizing marijuana, or legalizing medical marijuana, so make sure to look into what laws apply to you.
Things You’ll Need
Marijuana Seeds or Clones
High-quality hydroponic nutrients. I recommend using Fox Farms Hydroponic Liquid Nutrient trio and following the included instructions exactly
Pots to put your plants in. I recommend getting 1-5 gallon pots depending on the the size of your grow area and how big you want your plants to grow. Remember that you will have to water plants more often if they’re kept in a small pot, but larger pots will need more light.
Coco coir (mixed half and half with perlite for the best results) which can both be purchased cheaply online or at a hydroponic garden store. I personally used a coco coir hydroponic potting mix which is part of the Roots Organics line by Aurora. This potting mix already has perlite added to it and costs less than $25 for a big bag.
CFLs (Compact Florescent Lights). You can find a 42 watt CFL bulb at your local hardware store for around $10, and to start, you should have at least two of the 42 watt bulbs per plant.
Enough light sockets for all your light bulbs (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.
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, but you will need to get a timer by the time you start flowering your plant (about a month in).
A pH testing kit. You can find these in pet stores in the aquarium section, but it’s a better idea to get one specifically for growing(still under $20) as it tests for pH in a more useful range for growing.