How to make a marijuana clone box in 7 steps

In this article, I’ll illustrate exactly how to make a box for germinating and cloning marijuana plants.

The clone box will be separated into three levels, each with its own individual climate. One level is for germination, one is for growing seedlings and clones, and the last one is to vegetate and grow a few mother plants.

This system will be located in a cabinet in my office, so it needs to be clandestine.

I can’t have any visitors knowing about the marijuana plants in there. It must be locked, and it cannot release any air or light. I’ll list the items I used at the bottom of this article.I will install the following three items:

  • Lights
  • Exhaust fan with carbon filter (for fresh air)
  • Thermo/hydro meters (to control and measure the temperature and the humidity)

To increase the amount of light reflection, I will also make use of some white mylar foil.

The cabinet is quite large but I need to germinate a few hundred marijuana seeds every week. There are a number of ways to build a germination/clone box, but this is just one example. Use your own creativity when constructing yours and send me photos of your own endeavor. If you can describe your box in detail with instructions and illustrations on how to build it, then I may place it on my website.

First check this instruction video and subscribe to my channel.

1. Choose an adequate closet

In reality, any closet or cabinet will work for germinating seeds or making clones. The major issue is the location of the cabinet. Do people commonly go into the area where the cabinet is? You have to think about security and the ability of anyone to spot it when you choose a location.

My box is in my office cabinet, so I’ve got a lock on the metallic cabinet and the “rolling door.” I located this cabinet on an online auction and purchased it for about $20 (not too expensive).

The size of the cabinet is 120x45x150 centimeter(lxbxh)

2 images showing a closed and an open closet for your cannabis grow setup

2. Provide plenty of ventilation

CFL’s don’t produce that much heat especially by comparison to normal incandescent bulbs. So, the distance between the lamp and the plants can be relatively small. Still, a closet with 750 watts CFL’s can heat up over time. To combat this, I’m going to install a small exhaust fan that removes hot air from inside the closet and provides cooler, fresh air that’s CO2-rich from outside the closet.

The plants need CO2 because it is instrumental for photosynthesis. The plant needs oxygen and sugars, and it gets those from the combination of light, water, and CO2. The mother plants and plants in the vegetative state are most in need of CO2-rich air.

The scent of the marijuana plants can be noticeably pungent, so I’m attaching a small carbon filter to the fan, as well. The exhaust fan produces a vacuum in the closet, prohibiting air from escaping elsewhere. All the air that makes it out of the closet must go through the carbon filter, which kills the smell.

Because heat rises, I’m going to create a hole at the top of the closet. This is where all the electrical wire will go also.

3. Hang reflective foil on the wall

In order to make the most out of the light, having reflective material on the walls is a good idea. My personal preference is mylar foil because it reflects the light well and it also keeps the light from seeping out of the closet. You don’t have to do this, but it’s beneficial because the plants will get light from the side instead of just the top. This helps them grow faster. Aluminum foil and mirrors also work. Just ensure that you’re walls aren’t black!

Note: To improve humidity, you can spray the reflective walls with water.

DIY Marijuana clone box - Step 3 - 4

4. Divide into 3 levels

This closet needs one level for germination, one for seedlings and clones, and one for mother plants and plants in vegetative state.

The top-level should be for germinating seeds. Light isn’t important, but a consistent temperature helps. I install lights just for the heat (and also because I grow seedlings up there). There are about 10 inches between the shelf and the ceiling.

The middle level is for rooting clones and growing seedlings. There is enough room to grow 300 clones on this shelf. Clones and seedlings require about 1 to 3 watts of light each. I’m planning to install four 60-watt CFL bulbs. There are 15 inches between the shelves.

The bottom level is for mother plants and plants in vegetative state. They need the most space. I’m planning to install two 100-watt CFL bulbs with reflectors. There are 25 inches between the shelves.

5. Make holes in shelves to attach the light

The smaller plants require an equal distribution of adequate light. It’s easiest to just mount the light to the shelf above, and adjust the difference as needed. Install the light in the center of the shelf and connect it there with a bolt and a nut.

DIY Marijuana clone box - Step 5 Attaching light
DIY Marijuana clone box – Step 5 Attaching the light

Once you’ve attached the lights to shelves, take the electrical cable outside of the closet through the air hole. It’s a bad idea to mix water and electricity in the same small room.

Also read “Maintaining optimal lighting for cannabis plants”

6. Camouflage

To avoid raising any suspicion, you should camouflage your set-up with a few normal items. Place some books or plants on top of it. Maybe a tablecloth or other decoration would also work. I am going to place some mail, invoices, and a small plant on top of my box so that it blends in with my office.

camouflage of a marijuana grow box set-up

7. That’s it

This set-up will allow me to germinate about 200 seeds and create about 200 clones every week.

Shopping list:

  • 1 x closet
  • 6 x 60 watt cfl
  • 1 x 200 watt cfl with reflector
  • 14 x bold and nut
  • 1 x flange
  • 2 meter – ventilation hose
  • 1 x carbon filter
  • 1 x fan
  • Mylar foil

Now that you know how easy it is to build one of these boxes, you should try it yourself. But first, you have to purchase some seeds. Check out our seedshop for a wide selection of top-quality seeds.

High-quality marijuana seeds

Buy high-quality seeds

  • We ship daily to all U.S. states for FREE!
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We ship to the United States. If the order doesn’t get to you or the seeds don’t germinate, then you can get new seeds free of charge.


FAQs about cloning

If you purchase clones, how big should they be?

You can buy clones at any age, but if you are ready to plant, you want clones with good roots. If you are buying a cutting that does not have a good root system yet, make sure that it has at least a couple of nodes on it, so that those roots will be able to form. If you’d like to purchase seeds instead, check out my Seed Shop.

Why shouldn’t you clone autoflowers?

If you take a cutting from an autoflower, your yields will be significantly lower. This is because the clone will not have that much time to grow more buds. Since it is autoflowering like its mother, it will simply continue the flowering stage (with fewer buds) instead of reverting into a temporary veg stage like non-autoflowering plants. Here’s more on growing autoflowers.

What is etiolation?

Etiolation is a method of survival that flowering plants use when there isn’t enough light. It causes the plant to shift more of its energy underground and seek out nutrients from its roots rather than the parts existing above ground. In general, this process is a bad thing, however, when you are trying to grow roots, a little of this can be good.

When should you place clones outside?

Clones are ready to transplant once they are fully rooted. You can place your clones outside late Spring but wait until it is at least 50 degrees Fahrenheit. You should also make sure there is enough time left in the season for your plant to continue growing in size before it flowers, or else, keep it inside under lights. For more on scheduling your outdoor grow, read my Outdoor Grow Calendar.

Are cuttings sensitive to light?

When you create your own clones, you need to make sure the roots that develop are strong enough to support it. One way to encourage strong root production is to keep your cuttings away from light. Remember, roots normally form in the dark, moist environment of dirt. Your cuttings will need something similar. For more on light’s effect on cannabis, read this article.

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Robert Bergman


Robert Bergman is an Amsterdam-based marijuana grow expert who has years of experience from small grows to massive operations ... See profile

3 comments on “How to make a marijuana clone box in 7 steps”

  1. Unless you were thinking in auto flowering strains the room you just made for clones must have modular lights so you can easily change the colour of lights according to the stage. But then the room is to small… This plan needs rethink

  2. Robert now I know why you make the big bucks, that is a dam good idea on the cabinet, I am fixing to get mine started, thanks for the info, keep up the good work robert