One of the best ways for an indoor cannabis cultivator to maximize efficiency is to set up a perpetual garden. In this type of garden, a grower immediately replaces harvested plants with new, ready-to-flower plants, thus creating a continuous growing cycle.

For a perpetual garden to work properly, a gardener must have a dedicated area for each stage of growth: cloning, vegetative, and flowering. The idea is to have plants in every stage of growth ready to move into the next stage when necessary.

So, when plants are harvested from the flowering room, a grower immediately replaces them with plants from the vegetative area, which are in turn replaced with rooted clones from the cloning area. And, finally, the rooted clones are replaced with new cuttings.

There are a few different ways for a marijuana grower to implement a perpetual garden. The two most common techniques are continual harvest and full harvest replacement.

Continual Harvest Technique

Continual harvest is a type of perpetual gardening where a horticulturist continually harvests plants on a weekly, bi-weekly, or monthly basis. To stay on schedule, a grower needs to take new cuttings every week, two weeks, or month, depending on how often they want to harvest (a grower should take at least twice as many cuttings as they will harvest to give themselves some leeway against any problems that may arise and the opportunity to choose the healthiest and most vigorous rooted clones). As plants are harvested from the flowering room, the same number of plants are moved from the vegetative room to replace the harvested ones. At the same time, the same number of plants are moved from the cloning area into the vegetative room.

Read also: Transition to Veg Phase: Hardening-Off and Transplanting

For this to work properly, a grower must either have two separate flowering rooms or a flowering room that can handle plants at different flowering stages. If the plants are at different places in the flowering stage, it can be very difficult to have all of them on the same feeding schedule (a cannabis plant in the first week of flowering has different nutritional requirements than one in the sixth week of flowering). As such, a hydroponic system where all plants share the same nutrient solution is not a good fit for a continual harvest perpetual garden. This garden set-up is more compatible with container growing, as plants in planting containers are more mobile and can be individually fed specific nutrients for the stage of flowering they are in.

Pros and Cons of the Continual Harvest Technique

Some of the advantages of a continual harvest garden are relatively simple timing and an evenly spread out harvest/work load. Also, a grower harvests more often with this set-up, meaning they get to enjoy the fruits of their labor more regularly.

The disadvantages of a continual harvest garden include maintaining the various feeding regiments for the plants, the lack of compatibility with recirculating hydroponic systems, and the inability to treat pest insects or pathogens. This last disadvantage can cause serious issues; if a pest or pathogen rears its ugly head, eradicating it is more difficult because a continual harvest flowering room contains plants in all stages of flowering.

Full Harvest Replacement Technique

Another perpetual gardening technique is harvesting the entire flowering room at once and then replace all those plants with others from the vegetative area. The timing of a full harvest replacement technique can be more difficult than it seems.

To be mature enough to go into the flowering room, vegetative plants must have enough time to grow. However, if they are left in the vegetative area too long, plants can become overgrown, root bound, or stressed in other ways that could hinder their performance in the flowering room.

In a full harvest replacement garden, the first thing a cannabis grower should do is learn about the plant variety they plan on growing. They should pay close attention to the amount of time it takes that variety to mature to the desired size for flowering, as well as how long it takes to finish flowering. Most cannabis varieties have an average flowering period of eight weeks, but the duration of each strain’s period will vary. To harvest larger plants, a grower can keep their plants in vegetative growth for four to six weeks (a much shorter period is needed for smaller flowering plants in a screen of green, or ScrOG, garden). Once the vegetative duration is determined, a horticulturist can add two weeks to the timeline to account for cloning.

Read also: Getting Your Cannabis Grow Off to a Great Start

Say a grower chooses a cannabis strain that takes exactly eight weeks to reach maturity. This same variety takes five weeks of vegetative growth to reach the desired size for flowering. If the grower adds on two weeks for cloning, the total is seven weeks. This means a grower should start the cutting/cloning process seven weeks prior to harvest, or one week into the flowering cycle, to effectively execute the timing on a full harvest replacement perpetual garden.

Pros and Cons of the Full Harvest Replacement Technique

The advantages of a full harvest replacement garden include uniform feeding regiments for all the plants in the flowering room, the ability to treat pest insects and pathogens more effectively, and the ability to run high-performance recirculating hydroponic systems. The disadvantages include the heightened work load around harvest time, timing issues, and longer periods between harvests.
Regardless of the technique, implementing an effective perpetual indoor garden is a great way to maximize a grower’s return on investment and get the most harvests per year. While creating an everlasting garden may seem overwhelming at first, a cannabis grower can experience less troubles in their quest if they take more than enough clones and understand the timing of their chosen plant variety. Once a grower has a few harvests under his/her belt, growing a perpetual garden can become second nature.