Marijuana Hydroponics Basics

Marijuana hydroponics made easy. Grow your own marijuana hydroponic garden. New age marijuana hydroponics systems. How to build your own marijuana hydroponic garden. Introduction to marijuana hydroponics, passive hydroponic systems and active hydroponic systems

How to Build Your Own Marijuana Hydroponic Garden

How to Build Your Own Nomadic, Marijuana Hydroponic Garden On a Limited Budget

Written, Maintained and posted occasionally to rec.gardens and alt.hemp by Jeff Burchell (burchell@cats.ucsc.edu)

Introduction:

These are plans to make a fairly portable, and very inexpensive water culture (advanced hydroponic) system. These plans only explain how to make the garden itself, and do _not_ explain how to use/maintain it. If you plan on using this garden, you should get yourself a good book on hydroponics, and look it over (especially the parts about what nutrient solutions to use, your garden vareity Miracle-Gro won’t do the trick).

Disclaimer:

I am intentionally leaving out those parts about plant nutrition, light cycles, etc. so as not to appear to be writing a guidebook for growing marijuana. It is also to make you seek out _another_ source of information so your knowlege of hydroponics comes from more than just this file. I do not grow marijuana, and never have. I’m just a high-tech home gardener with information to share. If you are caught growing marijuana while using the system described herein, don’t even think of running to me, I didn’t tell you to grow marijuana. In fact, I’d suggest planting a crop of cherry tomatoes, which can be fooled into producing fruit indoors year round, and is a very easy plant to start hydroponics with.

Materials: 1 5-10 gallon bucket
2 Pieces of PVC or ABS pipe, 8-10″ long, 5″ or greater diameter.
4 Caps for PVC/APS pipe ends.
1 waterpump capable of about 50 Gallons Per Hour (you will need a bigger pump if you choose to make this a larger system)
4′ of hose that will fit the waterpump (often 3/8″)
1 TEE joint (or Y-splitter) that fits the water hose
4 clamps for the water hose (one for pump to hose, and 3 for hoses to TEE fitting.)
1 Airpump, airstone, and some airline from a fish tank.
1 Can White epoxy based spray paint
1 Can Black Epoxy based spray paint

1. Everything must be made light tight. Paint all hoses, the bucket, the PVC/ABS (which will be called PVC from now on) and the lid of the bucket with a layer of black paint. Let it dry overnight, and then cover it with a layer of white paint (to make it reflective, and reduce the temperature of the nutrient solution).

2. Take each of PVC pieces and drill a 1″ hole in the side, about one inch from the end. Then epoxy the caps onto the ends of the PVC.

3. Drill the inlet/outlet holes (these should be located on the caps of the PVC).

The inlet hole should be as low as possible (as close to the wall of the PVC), and the outlet hole should be as high as possible)

4. Now cut two 5″ holes in the sides of the bucket (close to the top), and epoxy the PVC in place, so about 2″ of pipe (and the outlet hole) are inside the bucket, and the 1″ hole is facing straight up.

5. oxygen into the nutrient solution, and not to dissolve CO2. CO2 can kill rootsystems. If you are growing outside, or not enriching CO2, then the pump can sit anywhere.

6. Place the waterpump in the bottom of the bucket (assuming it is a submersible one) and attach a hose to it. long enough to reach the top of the bucket. Cut a hole in the lid of the bucket for this hose to go through. Then attach the TEE fitting to the hose. Now attach hoses to the free ends of the TEE, and run them to the inlet holes on the end of the PVC pipes. Use clamps on the TEE fitting and on the pump itself, but use epoxy to attach the hoses to the PVC. This seal must be completely water tight. Let them dry for 24 hours.

7. Put some water in the bucket and turn on the pump. What should happen is the PVC pieces will fill with water, and then when they are full, they should begin to continuously drain out the outlet holes, and back into the bucket. If you are getting leaks anywhere, fix them immedately. If water is coming out of the 1″ hole on the top of the pipe, then either your pump is too strong, or your outlet hole is too small. Fix one or the other.

8. Empty the system (hint, remove the hose from the pump to drain the arms), and replace the water with some form of hydroponic nutrient solution (look in a hydroponics book for details on what exactly to use, or visit a gardening store, and ask)

9. Place your plants into the system. The best way I have found to do this is to take a 1 1/8″ garden hose and cut a 1″ tube off of one end. Then slit the tube down one side. Wrap the stem of your plant (just above the roots) with polyester fluff (available at aquarium stores, for stuffing into external water filters) and then wrap the garden hose around the fluff. Then force the hose into the hole at the top of the PVC arm. People also have used rubber stoppers.

10. Turn on the air/water pumps, and let your garden grow.

Comments:

This is obviously just a small setup, but these plans can easily be modified for much larger systems, using longer pieces of PVC, or more than one pair of arms, and a larger bucket to hold the nutrients (I’ve seen one made with a 55 gallon drum, and 8 seperate arms, each holding 4 plants)

I personally use this setup indoors (under a skylight in my apartment) to grow 2 cherry tomato plants. What you do with your own garden is your own business, and Obviously I can’t be held responsible if you choose to grow anything illegal.

Starting Marijuana Seeds:

This system is not for seeds. Either purchase small plants, or start your seeds in a pan of vermiculite, flooded with 1/2 strength hydroponic nutrient fluid. When they are about 4-6 inches tall, they are ready to be moved to the system. Remove them gently from the vermiculite, using clean water to get every last chunk off of the roots. Then wrap the stems in polyester fluff and garden hose (see above)

Nomadic, Clandistine, Hydroponic Garden

I’ve been exploring hydroponic gardening lately, and thought y’all might be interested in hearing about my setup:

Materials -> 1 Footlocker or trunk, bigger is better.
1 Rubbermaid dishpan that just fits on the bottom of the trunk, when the trunk is turned on its side (this will make more sense in a few minutes, I used a 12 quart one)
3-4 blocks of FLORAL FOAM (Preferably agricultural grade, as it does not have preservatives in it, but Oasis will do if it is completely rinsed/soaked first)
1 Muffin Fan (look in computer surplus stores)
1 50 WATT High Pressure Sodium lamp (Or your lamp of choice)
1 roll of tin foil

Comments on Cost ->

If you bought all this stuff, it would run about 100 bucks… However, I got my trunk at a yard sale for $5, had the fan lying around, and through some creative scrounging on a public bike trail late at night, came up with the HPS lamp and ballast for free. The dishpan came from a ‘Everything’s a dollar’ store, and foam is cheap… I think I spent $30 total (including fertilizer, which I will discuss later)

What to do with this stuff->

First, cut the handle off of one end of the trunk, then stand the thing up on that end. Sitting it on a phone book with the door hanging off the end makes it much easier to open and close.

Then install the fan… I put mine on the top of the box, but It could go in the top back corner if light leakage is important. A good deal of light will be exiting the fanhole (well, more than anywhere else)… keep this in mind. I also painted the fanblades white in an attempt to reflect the light back into the box, but Im not sure if it worked… it probably isnt necessary.

Put some intake holes along the bottom of the box, these will be covered with foil later, so not too much light will be leaking out.

Cover the entire inside of the box with foil, excluding the fan area, and where you plan on installing the lamp. I used duct tape to affix it to the walls/door, and I LEFT IT UNATTATCHED AT THE BOTTOM so air could come through the intake holes.

Install the lamp! I put mine at the very top center of the door, with the bulb sticking straight out, so it enters the rest of the box when the door is closed. This made it easier to wire, but In the future, I would put it on the back wall of the box, as less of your room will be illuminated when you open the thing (it’s kind of like opening up the sun).

Thoughts on Lamps-> According to Ed Rosenthol (believe him if you want to, ignore him if you dont) HPS lamps are some of the best growing lamps made, especially when efficiency is an issue. These lamps give off an amberish glow, and are often used to light parking lots, bike trails, etc. They operate on a very high voltage, and require a transformer or ballast to work. Metal Halide lamps (used in photographic and theatrical lamps) are smaller, and much whiter, and usually do not require ballast, but they use up a hell of a lot more energy

I used a Flurescent to sprout the plants, and switched to HPS after they had developed 3 sets of leaves (about 48 hours after germination) This was acceptable.

Next, it is time to deal with the foam and plant. I soak the foam overnight in a nutrient-water mixture (more on that later) after rinsing it extremely well. Then I cut a brick or 2 into 1″ cubes, and plant one seed in each cube. Planting in foam means you place the sead on the foam, and push it in with a small wire or something similar, so the seed is surrounded as much as possible by the wet foam. The cubes are placed in the dishpan, and 1/2″ of water-nutrient mixture is added to the pan. The foam wilt yet, no do I especially care. I just plant a LOT of seeds, and then use the best seedlings for my gardening. Usually a smoking-buddy or someone will take a free marijuana seedling off your hands with a minimum of hassle.

About 3 days after germination, a few pairs of leaves should’ve formed. Now is the time to transplant. And transplanting is the glory of foam. All you need to do to transplant things growing in foam, is put the small block of foam (with the plant in it) on top of the larger block , and rub them together a few times. The roots will grow out of the small cube, and into the bigger one in a matter of days. I managed to find foam in 12″ cubes… cutting these in half gave me 2 pieces of 12″x12″x6″ foam, and each of those can easily hold one plant, probably 2. I personally grow only one plant in each trunk, but 2 smaller ones are probably perfectly acceptable.

Lighting-> When I transplant is when I turn on the HPS lamp. It then stays on for 24 hours/7days until the plant is 8-15 inches tall. Then it is time to force flowering. This can be done by giving the plants a 10-16 hour dark period in each 24 hour day (this should be done using a cheap timer like people use when they go away on vacation in an attempt to foil burglers) In a matter of 3 weeks, sex should be apparent on the plants… REMOVE THE MALES. Keep the dark period constant until it is time to pick, dry and enjoy.

A word on water-nutrient mixtures->

Floram foam should be totally inert, meaning it does not provide the plant with ANYTHING except something for the roots to grow in. Thus all nutrients that the plant would get from the soil MUST be in the water. Read a few books on hydroponics to figure out what mixture suits you best, I personally use a liquid plant food that shows on its label an N-P-N count of 10-15-10. This seems to work fairly well for me. I know people who use 20-20-20, and quite a few who use different foods during different stages of growth. Read up on the subject and decide for yourself.

Anyway, this was not ment to be a ‘HOW TO GROW WEED’ type of post, but apparently it has become one (sort of). It was ment to talk about my grow room, as it was described earlier in this post. I have found that a single plant can grow to maturity without any trouble in this space, and 2 smaller plants (forced to flower at about 8 inches, instead of the 10-12 that I personally use) would probably be ok too.

This grow room is very portable (unplug it and take it with you) clandestine (it looks like a trunk to me (not an uncommon thing in a college dormatory if you are a student), and it can be locked with a padlock) and effective (trust me!)

I assume one could grow using standard soil and such in this thing, but I have had great success with foam, and it is much easier to keep it watered. Rockwool has been sugested to me as a medium, but I dont even know where to buy it… apparently it is much like foam in that it is inert, and transplanting is a breeze.

Introduction to Hydroponics

If you’ve ever grown a backyard tomato, or kept a coleus alive through the winter, you have all the expertise you need to grow plants hydroponically. Quite simply, hydroponics is the method of cultivating plants without using soil. The plants are grown in a non-nutritive medium, such as gravel or sand, or in lightweight, man-made materials such as perlite, vermiculite (a mineral-mica nutrient base), or Styrofoam. Nutrients are then supplied to the plants in one of two ways: either by soluble fertilizers that are dissolved in water, or by time-release fertilizers that are mixed into the medium.

The advantages of a hydroponics system over conventional horticultural methods are numerous and varied. Dry spots and root drowning do not occur. Nutrient and pH problems are largely eliminated, since the grower maintains a tight control over their concentration. There is little chance of “lockup,” which occurs when nutrients are fixed in the soil and unavailable to the plant. Plants can be grown more conveniently in smaller containers. And, because there is no messing about with soil, the whole operation is easier, cleaner, and much less bothersome than it would be with conventional growing techniques.

Most hydroponic systems fall into one of two broad categories: passive and active. Passive systems, such as reservoir or wick setups, depend on the molecular action inherent in the wick or in the medium to make water available to the plant. Active systems, which include the flood, recirculating drip, and aerated water systems, use a pump to send nourishment to the plant.

Most commercially made “hobby” hydroponic systems designed for general use are built shallow and wide, so that an intensive garden with a variety of plants can be grown. However, most marijuana growers prefer to grow each plant in an individual container. Indoors, a three-gallon container is adequate. Outdoors, a five-gallon (or larger) container should be used if the water cannot be replenished frequently. Automatic systems irrigated on a regular schedule can use smaller containers, but all containers should be deep, rather than shallow, so that the roots can firmly anchor the plant.

Passive Hydroponic Systems

Last month we introduced you to passive marijuana hydroponics. In this installment of Ed’s Grow Tips, we outline two passive systems that are inexpensive and easy to maintain. Now you too can do it hydroponically!

The Wick System

The principle underlying this type of passive system is that a length of 3/8- to 5/8-inch thick braided nylon rope, used as a wick, will draw enough nourishment from a reservoir filled with a water/nutrient solution to keep a growing medium moist. The container, which holds a rooting medium, has wicks running along the bottom and dropping through small, tight-fitting holes to the reservoir. Keeping the holes small makes it difficult for roots to penetrate to the reservoir. By increasing the number or length of the wicks, or their thickness, you can increase the amount of water delivered to the medium. A three-gallon container should have two wicks; a five-gallon container, three wicks. The wick system is completely self-regulating: the amount of water delivered depends on the amount lost through evaporation or transpiration.

The medium: A 1-1-1 combination of vermiculite, perlite, and Styrofoam makes a convenient medium, because the components are lightweight and readily available. Vermiculite alone sometimes develops too air-free an environment and becomes compacted, so that a tall plant might eventually tip over. Perlite, which doesn’t compress, keeps the medium loose and airy. Styrofoam beads hold no water, and therefore help keep the medium drier. Pea-sized chopped polyurethane foam, gravel, sand, and lava can also be used in a medium. No matter which materials you use, the bottom inch of the container should be filled only with vermiculite, which is very absorbent, so that the wicks have an optimum medium for moisture transfer. Keep in mind that each medium has a maximum saturation level – beyond that point, an increase in the number of wicks will not increase the level of moisture.

Construction: Cut four holes, about 1/2″ in diameter, in the bottom of a three-gallon container. Run the wicks through the holes so that each end extends about three inches outside the container. Unbraid the wicks to aid absorption. Put two bricks in the bottom of a deep tray (an oil drip pan will do fine), into which you’ve poured the water/nutrient solution, then place the container on the bricks so that the wicks are immersed in the solution. Replenish the solution as it is absorbed.

A variation on this system can be constructed by using an additional outer container rather than a tray. With this method, less water is lost through evaporation. To make sure that the containers fit together and come apart easily, place the bricks in the bottom of the outer container with the water/nutrient solution until it comes to just below the bottom of the inner container.

The Reservoir System.

Even simpler to use than the wick system, you need only fill the bottom two or three inches of a 12-inch-deep container with a coarse, porous, inert medium such as lava, ceramic beads, or chopped pottery, and then pour in the nutrient/water solution. Variations on this method include a plastic flower pot or plastic growing bag placed directly in a tray or pail of nutrient/water solution.

Watering: All passive systems should be watered from the top down, so that any surface buildup of nutrient caused by evaporation will be washed back to the bottom.

Active Hydroponic Systems

Last month we introduced passive hydroponic systems. In this installment of Ed’s Grow Tips, we will explore active hydroponic systems.

The Flood System.

The flood system consists of a tub or container holding a medium that is completely flooded on a regular basis, usually once, twice, or three times daily, depending on the growth stage and environmental factors. The medium holds enough moisture between irrigations to meet the needs of the plant. First-generation commercial greenhouses using this method were usually built with long beds of gravel that were systematically flooded. Today, the flood system is most often used with individual containers, where each container is attached to the reservoir by tubing or by a leak-proof seal.

The medium: With this system, growers have a choice of mediums, including sand, pebbles, chopped-up rubber tires, pea-sized lava, gravel, and vermiculite-perlite-Styrofoam mixtures. A recommended mixture for this setup would be one part each of perlite and Styrofoam, and two parts vermiculite, or one part vermiculite and four parts lava. Note that because perlite and Styrofoam are lighter than water and will float if this system is fully flooded, neither should be used as a stand-alone medium with the flood system.

Construction and maintenance: A simple flood system can be constructed using a container with a tube attached to its bottom and a one-gallon jug. Fill the container with the medium. Each day, pour the water/nutrient solution from the jug into the container, holding the tube up high enough so that no water drains out. Then let the tube down so that the water drains back into the jug. Some water will have been absorbed by the medium, so fill the jug to its original level before the next watering. The plants’ water needs increase during the lighted part of the daily cycle, so the best time to water is when the light cycle begins. If the medium does not hold enough between waterings, water more frequently. Flood systems can be automated by using an air pump to push water from the reservoir into the growing unit.

The Drip Emitter System.

Drip emitters are complete systems that can be bought in nurseries or marijuana hydroponics garden shops. They have been used for years to water individual plants in gardens and homes. They can also be used with a central reservoir and a pump so that the water/nutrient solution will be redistributed periodically. If you choose this system, make sure to buy self-cleaning emitters so that the dissolved nutrients do not clog them with salt deposits. Start pumping about a gallon every six hours during daylight hours. Drip emitters can be used with semiporous mediums such as ceramic beads, lava, gravel, sand, or perlite-vermiculite-Styrofoam mixtures.

The Aerated Water System.

The Aerated water system is probably the most complex of the hydroponic systems, and because it allows the least margin for error, it should be used only by growers with previous hydroponic experience. To put together an aerated water system, you must first construct a clear air channel in your container. This is done by inserting a plastic tube cut with holes through the medium. Then a fish tank aerator is placed at the bottom of the plastic tube. The air channel allows the air to circulate without disturbing the roots, and the roots use the oxygen dissolved in the water.

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