With medical marijuana now legal in many states, including three new entries in the recreational marijuana category as of November 3, 2014, it has become increasingly valuable to understand how to get the desired outcome from your garden while staying within legal guidelines.

In part one of "The Eternal Harvest" guide to growing weed, we answer two primary questions: What is perpetual gardening? And, why would I want to grow a perpetual marijuana garden? We will also discuss advantages of legally growing weed verses buying it from a local supplier, and we will cover the equipment needed to set up the perfect perpetual hydroponic cannabis garden using Black Dog LED grow lights.

In the states that have passed cannabis legislation, a common trend is to allow adults (21+) to grow six (6) marijuana plants, with three plants flowering, and three plants in a vegetative state (not-flowering) at any one time. Please note that there are exceptions, such as Oregon where adults over the age of 21 are permitted to grow four (4) rather than six (6) pot plants.

Please note that recommendations made in this article in no way support, encourage, nor condone breaking any laws, but rather how to get the greatest results from your garden while staying within the permitted limits. Even in states that do permit recreational marijuana, local laws and regulations may differ radically. If you have doubt about the legality of your garden, it's best to check with your local authorities rather than make assumptions. Ignorance of the law is not a excuse for not following it, ultimately it is the responsibility of the grower to stay informed and within the established guidelines.

What is a perpetual garden?

A perpetual garden is a term commonly used to describe a method of growing, where plants are cultivated at different stages of development, staggered so that when one plant matures and is ready for harvest, the next vegetative plant is ready to take its place. This is accomplished using two distinct grow spaces (tents in our example) isolated and sealed off from all external light. The smaller tent is used to grow young plants, training and prepping them for flowering. This tent is also used for rooting cuttings and starting seeds. The light in this tent must be on for at least 18 hours a day and left on all hours in some cases. The second, larger tent is used strictly for flowering. The light inside turned on for 12 hours per day (12 hours uninterrupted darkness triggers marijuana to flower). This 12 hours on, 12 hours off light schedule will never change when growing a perpetual garden.

Why Would I Want To Grow A Perpetual Marijuana Garden?

For most gardeners, the goal is to grow high quality buds that are fresh and readily available year-round. A perpetual garden is one of the best horticultural techniques to accomplish that goal. Before gardening under artificial light became a reality, unless you lived in a perfect location or had a greenhouse, a consistent source of fresh bud could be tough to come by,. Now using the techniques discussed in this article, you should never have to worry about the next "dry spell" or "drought", and always have sticky nugs on hand.

Benefits of Growing Vs. Buying Retail

Gardening itself can be good medicine. It teaches biology, chemistry, entomology, and especially patience. For those concerned about quality or potential contamination from disease, pesticides or other chemicals; growing your own cannabis is the only way to be certain about what you are putting into your body. If cannabis gardening isn't your thing, then buying marijuana from a recreational cannabis dispensary or pot shop may be your best bet. If you do purchase cannabis from a retail shop, here are a few basic recommendations:

  • The store should have a good track record.
  • The products they sell should be tested (not only for THC/CBD content, but also for mold, insecticides, fungicides and other contaminants).
  • The Bud Tenders should be able to tell you what to expect from each strain and how to properly smoke, ingest, or consume the appropriate amount whether it's dried flower, wax, oil, or edible.

Growing weed indoors just one time will give you an incredible insight over those that don't know where buds really come from. You will know what to look for when purchasing weed from an unknown source, and understand the process behind growing, harvesting, and curing quality herb. For those that are never going to grow pot, but are still fans, sitting down for a few hours to trim with a friend is a good way to get experience and help out at the same time. Lastly, if you are relying on someone else to grow pot for you, just know that anything can happen, and if you do run into a drought, beggars can't be choosers.

Equipment for the Ideal Perpetual Garden Setup:


Grow Tents:
Hydroponic Components:
  • 1 – 2' x 2' Flood Tray/Table
  • 1 – 20 gallon reservoir with Lid
  • 1 – 3' x 3' Flood Tray/Table
  • 1 – 40 gallon reservoir with Lid
  • 4' of ¾" water tubing
  • 4' of ½" water tubing
  • 2 – Flood and Drain Fitting kits
  • 4 – 15 minute analog timers
  • 1 – Water Pump with rated flow rate of ~400gph
  • 1 – Water Pump with rated flow rate of ~200gph
  • 2 – Water Pumps with rated flow rate of less than 100 gph (smaller is better)
  • 1 – Tall Boy, carbon/sediment filter with KDF-85 upgraded carbon filter
  • 1 – Blue Lab Combo Meter
  • you may also need a heater or chiller to maintain the water temperatures in the reservoirs.
Containers and Growing Media:
  • 9 – 8" Fabric or Plastic Mesh Bottom Pots
  • 1 – 45L Bag of Clay Balls (Hydroton, Hydrokorels, Plant-It)
  • 1 – 2 cubic foot Bag Grodan Rock Wool Mini-Cubes
Choose a well known manufacturer like General Hydroponics, Botanicare, House & Garden, etc., then follow the directions. Talk with local hydro shops and growers and see what they are using. Follow the recommended schedule or make a feeding schedule and follow it. For a lot more about nutrients and other LED growing tips, click here.
Environmental Controls:

Trip Through a Perpetual Pot Garden - A Plant's Journey From Cutting To Cure

There are endless ways to find marijuana cuttings and seeds but they are outside the scope of this article, and we will assume that 3 established cuttings/seedlings are available when starting your garden. For the first 4-6 weeks, your new garden will only have 3 plants vegetating. This will be the only time in a perpetual cannabis garden when no plants are flowering. After the initial veg, the schedule is basically consistent.

Here's a description of the timing in a perpetual garden, which can also be seen in the graphic below that also depicts how things flow once underway:

  • It will take 1-2 weeks for cuttings/seeds to root and begin to develop which is designated as purple "Rooting" in the diagram, before moving on to the vegetation period (veg). During the first 1-2 weeks of veg, established starts are transplanted into larger containers/pots.
  • After successful transplantation, the young plants are moved under intense LED light, light that will be turned on for at least 18 hours per day. The veg plants are topped and trained over the next 4 to 6 weeks. During this time, managing the size of the plants is crucial. There are a lot of techniques to slow or increase growth rates, such as lowering the fertilizer strength, pruning, training, and lowering air temperatures. Two weeks before moving to flower, new cuttings are prepared for the next veg cycle.
  • As soon as the cuttings take root, the mature veg plants move into the flower tent. The flower light is timed to be on for 12 hours and off for 12 hours. There are now three plants in flower, and three veg plants in the rooting stage.

Below is a diagram showing the timing and flow of various plants at different stages of growth. Notice that there is never a time when more than 3 plants are flowering or vegging, staying within established legal guidelines, and 6 plants are always growing.