Perpetual Harvesting: How To Crop Cannabis All Year Long

If there’s anything that feels better than harvesting some beautiful cannabis plants, we haven’t heard of it yet.

Since you’re reading this article, we bet you’re on the same page. We’re also sure you’d like harvest to come around more than once a year. Well, if you have enough space, the right tools, and knowledge of certain techniques, you can actually pull it off!

Now, that doesn’t mean defying the seasons for multiple yields won’t be tricky at first. We know that as well as anyone, so we’ve decided to write up a full explanation of perpetual cannabis harvesting. Read on for a step-by-step breakdown of the process.

How to Harvest Cannabis Multiple Times per Year

If you grow your cannabis plants as usual and try to achieve multiple harvests, you’ll end up tired and sorely disappointed. You’ll have to work smarter and harder to rake in more than one crop per year, and your budget will play a major role.

Specifically, the key to multiple harvests lies in the manipulation of the flowering and veg process, along with the reorganisation (and possible expansion) of your growing space.

Speaking of that, you’ll need a decent amount of room inside, or space for a greenhouse outside, before you start. In turn, you’ll want to make room for separate seedling, vegetative, and flowering spaces. As we’ll explain later on, this is vital to ensure you don’t hinder the growing process for any set of plants.

What Are the Advantages of a Perpetual Harvest?

While we’ve been listing off all this stuff you need to get and do, we imagine you’ve been thinking about whether all the trouble is worth it. Despite our positive opinion on it, we would say it honestly depends.

If you’re in an area with poor sunlight or barely have room for your current growing operation, it might not be worth the trouble. But, imagine what you’d save with a year-round supply of your own buds! Regardless of your expertise or the scale of your growing operation, there’s no need for empty stash jars.

How a Perpetual Cannabis Harvest Works

Was that enough to sell you on the idea? We thought so. Now, with that out of the way, it’s time to cover how exactly a perpetual cannabis harvest works.

Equipment and Supplies

To kick off your multi-harvest operation, you’ll need:

• Extra Growing Area/Tent

Since you’ll be simultaneously growing two separate groups of cannabis plants, you’ll need to give them their own dedicated spaces. As they’ll be growing by different lighting schedules, the areas also need to be separated by a wall.

You could potentially use one large grow tent or room, but you’d have to install a sturdy wall, as well as a door to move between the two spaces.

As we mentioned before, one space is dedicated to the vegetative stage, while the other houses flowering plants. Plants in the former, naturally, don’t need as much space. So, even if you do need an additional tent, it doesn’t have to be anywhere near as big as the flowering room.

• Additional (Weaker) Lights

As you’ll need a separate space to satisfy a different light schedule, you’ll need a new set of lights in turn. They don’t have to be as strong, thankfully, since plants in the vegetative phase don’t have the same light requirements as your flowering beauties.

• Light-Proofing Supplies

Since light pollution can significantly hinder flowering plants, you should have their space thoroughly light-proofed. This can be done with garbage bags, thick boards, or any other cheap, opaque material.

• Humidity/Temperature/Air Circulation Supplies

Lastly, since you’ll have more plants in your space than usual, you’ll need to keep a special eye on the humidity, temperature, and air circulation. If it gets too stuffy, for example, it could cause an especially intense mould infestation. Thankfully, you’ll only need to add in another fan, vent, and thermometer/hygrometer to keep your cannabis safe.

Hygrometer / Thermometer

(468)

View

Setting up Your Grow Area

As soon as you have all your supplies, it’s time to set up your growing spaces.

Seedling/Veg

Since seedlings and veg-stage cannabis plants have the same light cycle requirements, you’ll be fine keeping them in the same room. They should be kept in separate parts of the room, however, since the strength of the lights will differ.

Light-wise, for the seedlings, some small fluorescent T5 lamps, placed directly overhead, will be all they need. Those lamps should be on for 18 hours a day, and off for 6. This also applies if you’re starting with clones. However, with those, you’ll also want heat pads below them and over-arching humidity domes.

The veg-stage plants, naturally, will need more powerful lamps. Fluorescent T5s are fine here too, but you’ll preferably be using MH or LEDs instead. The latter two may cost more and require more electricity, but the extra yields they encourage are worth it.

Flowering

As your plants begin to mature, you’ll take them to a room where you’ve set up either HPS or LED lamps. Whichever you pick, you’ll have them on for 12 hours a day, imitating the daylight shift of the changing seasons.

You should also ensure you have fans and vents set up to keep humidity and temperature in check.

Crop Rotation

The real art of the perpetual harvest lies in managing crop rotation.

See, when your first plants hit the flowering stage, you have a lot more to do than play the waiting game. Immediately afterward, you have to get some clones or newly germinated seeds to take their spot in the vegetative space. From there, the cycle relies on the first set being harvested and cleared before the new plants are ready to begin flowering.

Now that we’ve explained that, we can offer another important tip.

Before you begin any sort of growing, you need to pick your seeds according to their flowering times. More specifically, the vegetative phase of the second set needs to take just as long as the flowering phase of the first. If the timing is off on either end, the cycle is doomed.

Taking Clones/Planting Seeds

Going along with that same piece of advice, you need to properly time when you take clones from your first plant set. In general, we recommend you take them from vegging plants when harvest time is around 3 weeks away. As far as planting seeds, you should leave enough time for them to germinate before they enter the vegetative space.

How to Achieve a Perpetual Cannabis Harvest: Indoors and Outdoors

With all your plans coordinated, supplies gathered, and spaces set up, it’s time to start growing. Let’s cover what a perpetual cannabis harvest looks like indoors and outdoors.

Indoors

First off, ensure that you have your two spaces ready to go, even if you’re not using the flowering room for several weeks. You should also make sure that air can properly circulate in your flowering room before there are any plants in there.

Then, once your young plants are ready, set them in the vegetative room. You should start preparing your next round of seeds and clones soon after, ensuring they’re ready to replace that first set in the vegetative room.

Afterward, once your first set of plants is ready to start flowering, move them to their dedicated space and ensure they’re on the right lighting schedule. At the same time, the second set should be ready to start the vegetating process. You can prepare a third set here, but we wouldn’t blame beginners or tired growers for stopping at two.

Once your first set is ready for harvesting, the real work begins. At once, you’ll be taking your harvested buds to your drying/curing space, moving your second set of plants to the flowering room, and, if you went for it, bringing your third set into the vegetative space.

Outdoors

Now, you can’t work exclusively outdoors when doing multiple harvests, but you can use nature to your advantage. This time, you’ll spend some time growing in a greenhouse and (partly) working with the seasons.

For your first set of plants, you can work with the seasons as usual, although you should have separate veg-stage and flowering-stage greenhouses (or one greenhouse divided). After the first round of the cycle is complete, you can start preparing your greenhouses like indoor spaces. Namely, you’ll outfit both with lights and light-proof the outside of your flowering space.

In turn, you should make sure that you have temperature control systems in place to prevent the greenhouses from getting too cold or warm.

How Many Times per Year Can You Harvest Cannabis Outdoors?

Now that you know how it’s done, you’re probably doing the math to figure out just how many harvests you can pull off in a year. It heavily depends on the size of your space and the amount of plants you’re growing, along with a variety of other factors.

Generally, however, growers successfully carrying out the process can get at least two very healthy harvests. A third isn’t far out of reach, either, but you’ll need to have ample energy and space. Theoretically, though, with the optimal amount of space, time, equipment, etc., you could pull off up to six harvests a year!

Managing Light Cycles to Control Cannabis Flowering

As we mentioned before, the light schedule is everything when it comes to perpetual cannabis harvests. The seeds you get may be blessed with the perfect flowering times, but you might not be so lucky. To bend the odds in your favour, then, you’ll have to learn how to tweak your light cycle to manipulate growth.

To get more specific, you’ll have to utilise a technique known simply as light deprivation.

When Should You Use the Light Deprivation Technique?

“But when, exactly, does light deprivation come into play?”

Remember how we were talking about getting the vegetative and flowering times of your plant sets on a matching schedule? Well, if you notice that your plants need to start flowering a bit faster, it’s time to bring light deprivation into play. It’ll trick your plants into thinking that autumn/fall is getting closer, which will cause them to rush even quicker toward harvest day.

How to Use Light Deprivation

Along with being majorly useful, it’s an easy process to manage whether you’re indoors or out!

• Indoors

Simply enough, once you feel your plants are ready to start flowering, shift their light cycle from 18/6 to 12/12. This will give them the impression the seasons are beginning to shift, and flowering will kick off right away. Get the schedule right, and you can save weeks of time over a year of growing!

• Outdoors

If you’re growing outdoors or in a greenhouse, get opaque tarps that can completely shelter your plants from light. Just like the covers for a flowering room, you need to make sure the tarp makes your greenhouse totally light-proof. If you can mimic a 12/12 schedule with this setup, you can induce flowering in no time.

Can You Harvest Multiple Times Using the Same Grow Room?

Now, as we’ve gone along, some of you may be lamenting a lack of space. With all this talk of separate rooms and spaces, you might wonder whether it’s possible to manage multiple harvests in the same room.

We won’t lie to you, it’ll definitely be difficult, and you won’t save much money compared to having a separate room or greenhouse. However, if it’s what you need to do, it’s still definitely possible, and you shouldn’t lose hope.

You can give yourself more room for error by growing autoflowers, as they’re fairly resilient and don’t require changes in their lighting schedule to bloom. In turn, you wouldn’t even need to have a separation between your vegetative and flowering spaces!

Final Tips for Perpetual Harvesting

To cap things off, we’ll offer you a little summary of final tips.

• As we said before, be careful when picking your seeds. Every strain has a different flowering time, and you don’t want to get caught in an out-of-sync cycle.

• Make sure you get a clear idea of your energy and water costs before diving in. You don’t want to get stuck with unmanageable bills halfway through the grow cycle!

• Keep the climate in mind, and make sure you buy whatever heaters and fans you need before putting seeds or clones in soil.

• Make sure you have enough room to dry, cure, and store multiple harvests!

Luke Sumpter

With a BSc (Hons) degree in Clinical Health Sciences and a passion for growing plants, Luke Sumpter has worked as a professional journalist and writer at the intersection of cannabis and science for the past 7 years.

Read full bio