Updated at: 16-03-2023 - By: Sienna Lewis

If you’re growing cannabis in a greenhouse and aren’t sure when to harvest it, just follow the signs. Timing is everything when harvesting cannabis, just like it is with any other greenhouse plant. If you don’t do this, all of your time and energy spent growing indoors will be for naught.

Why is it important for growers to know when to harvest cannabis? This is often done too soon, which is a common blunder among amateur growers. The downsides include a lower yield and weaker THC levels in the plants.

However, the THC content of the plants will decline if they are harvested too late. As a whole, a high-quality harvest is guaranteed by waiting for the optimal time to harvest cannabis. Since this is the most fruitful part of greenhouse cultivation, you shouldn’t rush through it.

Guide On How To Tell When To Harvest Cannabis Growing In A Greenhouse

It is strain-specific when determining the ideal time to harvest cannabis from a greenhouse. Flowering time for Indica is about eight weeks, while for Sativa it’s about ten. At the end of these times, both strains will be ready, while auto-flowering strains are ready ten weeks after sowing.

To be clear, these are just suggested timelines. With these calculations, you’ll have a better idea of when you can expect to harvest cannabis in a greenhouse. Visual indicators are the most reliable means of knowing whether or not a harvest is possible.

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Visual signs that cannabis is ready for harvest


When the trichomes on cannabis flowers turn a milky white, it’s time to harvest. When they are transparent rather than white, you know you’ve picked them too soon. To those unfamiliar, trichomes are the glands found on the plant’s blossoms and foliage.

As a result, you’ll need some kind of magnification to look for this component of the plant. The trichomes of a cannabis plant can be observed throughout its development. In the early stages of flowering, for instance, they may resemble crystals.

Cloudiness of the trichomes is a natural consequence of aging. However, keep in mind that half-cloudy trichomes indicate that the flowers are still not ready to be picked. Harvesting should occur at a time when the trichomes are mostly opaque, indicating a high THC level.

Keep in mind that an amber hue in the trichomes indicates a narcotic high, while a cloudy hue indicates psychoactive effects.


The leaves of the cannabis plant are one part that can be viewed without the aid of a magnifying glass. The fan leaves turning yellow may signal the beginning of harvest. The large, broad leaves on the plant are the fan leaves.

Be careful not to misinterpret this as a green harvest. Because of nutrient deficiencies, the plant may be exhibiting yellow leaves at this time. Many flowers on the plant, however, signal that harvest time is near.


The pistils of your cannabis plant look like tiny hairs and are located in the middle of the flowers. When the lines turn red, it’s time to start cutting flowers. Their color will also shift as the plant develops.

For instance, pistils begin life as white and eventually turn red, brown, or orange before they are harvested. Avoid picking if the majority of the pistils are still white. If the THC content is high, you should wait until about half of the leaves are red before harvesting.

As a result, the greater the number of colored pistils, the greater the THC content, and the greater the resulting physical high.

How To Harvest Cannabis In The Greenhouse


Remove each plant carefully from its base. It’s possible to gather the plants as a whole or just the branches you need. If you want to trim the buds in comfort, start with the largest leaves.


Dry or wet trimming are both acceptable methods for preparing cannabis for consumption. Dry trimming is preferable if you can regulate the humidity in the drying room and want to protect the flavor and aroma, while wet trimming is preferable if the humidity in the room is very high. Since wet trimming increases ventilation, it reduces the likelihood of fungal diseases.


The leaves should be tied in an upside-down direction at the base of the main stem before drying. The buds need about 15 days to completely dry out. Help the process along by keeping the room dark and the temperature between 64.4 and 73.4 degrees Fahrenheit.

After that, storing the flowers in an airtight glass jar will enhance their quality. For the first three weeks, you should give them a 10-minute break every hour. The ideal temperature and humidity for the storage area is 68 degrees Fahrenheit and 50 to 55 percent.

After the sixth month, ventilation is no longer necessary, and by the eighth month, the flavor and aroma have mellowed.

Harvesting outdoor cannabis guide

Outdoor cultivation of cannabis is likely to result in the lowest production costs. If you have a few high-quality cannabis seeds and a sunny, sheltered spot with average soil, you can grow your own plants outdoors. High-quality compost and fertilizer can be added to the soil as needed.

Great outdoor cannabis production is possible in a wide range of climates, not just those with year-round warm temperatures. In about 100 days (even less time indoors), high-quality autoflower seeds can be harvested after being germinated. Even in places where summers are brief, there is still enough time to plant, grow, and harvest autoflower seeds outside. The question is, how should cannabis grown in the open air be harvested, dried, and cured? Continue reading for some suggestions from the pros.

Harvesting advantages of autoflowers grown outdoors

The benefits to an outdoor grower of using autoflowering seeds are substantial. A large portion of the cannabis market is comprised of autoflowers due to their famed low-maintenance requirements. Their rapid growth and diminutive stature make them an efficient choice for quickly establishing covert vegetation.

  • Outdoors, autoflowers typically bloom from seed to harvest in about 100 days. That’s a lot quicker than photoperiod outdoor strains, making them a good choice for places with brief growing seasons.
  • Plants grown from autoflower seeds are typically less than 1 meter in height and quite stocky. These are much more discreet than the 3–4m tall plants you’d get from planting feminized outdoor seeds during the photoperiod.
  • Autoflower seeds require very little attention and care once planted. Grow easily and efficiently with little effort if you pick a sunny spot with high-quality, moist soil.

Harvesting advantages of photoperiod feminised strains grown outdoors

Feminized photoperiod cannabis seeds are the other primary option for growing cannabis outside. These can’t be grown successfully in summers that are only 100 days long, unlike autoflowering seeds. These larger plants usually take about 5 months to mature. Large yields are possible, though. It’s not unheard of for a 3m tall plant to produce more than 1Kg.

If you have a long enough growing season, you can pick your outdoor photoperiod cannabis plant just as the weather starts to turn. Feminized photoperiod cannabis seeds are a popular option for outdoor growers.

  • Choosing outdoor cannabis seeds with photoperiod genetics will result in the largest harvests.
  • If given the right conditions, plants are capable of reaching heights of 3–4 meters and widths of the same. Some farmers, however, find that such massive crops pose security and privacy concerns, as they are difficult to conceal.
  • Make sure your favorite outdoor photoperiod strain has enough time to finish flowering before the season ends.

Another perk of growing photoperiod feminized seeds is that they might bounce back from a pest attack or accident a little quicker than an autoflower would.

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The outdoor life cycle of an autoflower is predetermined, and it typically lasts around 100 days. Autoflowering plants have a shorter window of opportunity to recover from setbacks, so any damage they sustain during their prime may be fatal. When dealing with slugs, rabbits, and other pests, a plant with a longer growth phase before bloom may be able to recover slightly more quickly.

When to harvest outdoor cannabis, autoflower seeds vs photoperiod feminised seeds

From seed to harvest, autoflowers typically need about 100 days in the great outdoors (indoors, under optimal conditions, that number drops to about 75 days). As a result, growers in warm regions can reap two (or even three) outdoor autoflower harvests in a single year. That’s why autoflower seeds have caught on with outdoor growers recently.

The typical lifespan of feminized seeds grown outdoors is between five and six months. That’s a lot longer than an autoflower’s life span, but the payoff for the grower is typically larger harvests compared to those from autoflowers of the same size. Unfortunately, unless you are relatively close to the equator, you can only grow a single outdoor photoperiod crop per year.

It is important to note that growers of photoperiod feminized seeds can artificially force extra productivity from their plants by cultivating in greenhouses with blackout blinds. Creating artificial 12/12 light conditions can help growers “force” an early bloom and shorten harvest cycles. This method is also utilized by some balcony growers.

When to harvest outdoor cannabis according to trichome appearance

Many farmers keep an eye on the trichome resin glands as they change from transparent to cloudy and finally to a deep amber. This method is effective for both autoflowering and standard photoperiod outdoor strains.

To make precise up-close evaluations of the trichome appearance, many cultivators invest in a small magnifying glass (sometimes known as a jewellers loupe). An advanced digital microscope can also be purchased and does an excellent job of displaying the trichome structure.

Trichomes that aren’t clouded over

Cannabis with visible, colorless trichomes has a more vivacious, energizing effect. Still, the THC content may not have reached its maximum, and the buds may not be fully mature. Waiting for a little while longer is preferred by most outdoor growers because it results in larger yields and potent weed.

A trichome cloud

Your buds will be heavier if you wait until the clear trichomes have turned cloudy or milky. The result is a higher concentration of THC and more resin on the buds. Many cannabis farmers wait until the trichomes are mostly cloudy before they pull the plants. Some trichomes may have developed an amber hue by now.

Trichophyton rubrum

More and more of the trichomes on your buds will change from cloudy or milky to amber or red if you give them another week or two to mature. At this stage, some cultivators choose to harvest because they experience a more narcotic, heavy high from their cannabis. Many people believe that an abundance of red trichomes indicates an overripe harvest. Some cultivators, however, especially those whose focus is on medical marijuana, may prefer a heavier body high that also has a sedative effect.

When to harvest outdoor cannabis according to pistil (hair) colour

Many cannabis farmers also pay attention to the pistil color in addition to the trichomes’ appearance. The hairs that emerge from the buds. Early on, the pistils are typically white. They are getting ready to be harvested when they turn from green to brown.

50% of the stamens are brown

Cannabis harvest is quickly approaching, though growers often wait a little longer because many pistils are still white.

70% of the stamens are brown

Most of the pistils have turned brown at this point, but not all of them. Many farmers consider this a prime time to start harvesting.

Upwards of 90% brown stamens

This may be considered by some cultivators to be a fully developed crop of cannabis, producing a more potent and narcotic product. Some growers may find such buds to be overripe, but there are also many who believe that the extra time in bloom is well worth it. Nonetheless, it’s important to note that everyone’s endo cannabinoid system is slightly different and thus produces varying effects from cannabis.

When you grow your own cannabis from seeds, you get to decide exactly when to harvest it for maximum personal satisfaction (as opposed to leaving that decision up to an unknown grower/dealer). It’s been found that some people who use cannabis have very strong preferences for particular strains that have been grown to the ideal ripeness level for them.

Only brown stamens

In the eyes of the vast majority of farmers, a crop is overripe if all the pistils have turned brown.

When you’re next cultivating cannabis seeds, try harvesting (and drying) a variety of bud stages to see how the effects vary. It’s possible, though unlikely, that your preference will strongly affect the timing of future cannabis harvests.

When to harvest your outdoor crop according to sativa vs indica genetics

The time until harvest can be roughly estimated if you know the cannabis strains’ genetics. Your results will vary greatly depending on the latitude at which you are growing and the weather conditions that prevailed throughout the duration of the grow. However, indica genetics typically flower sooner than sativa or haze ones.

Flowers in the northern hemisphere tend to bloom later than those It’s possible that the harvest of haze strains won’t begin until late November. In northern Europe, growers would have to wait until spring to plant their seeds outdoors. An important part of being a skilled outdoor cannabis grower is knowing which strains will thrive in your environment.

Drying cannabis buds grown outdoors

In order to successfully dry your outdoor-grown cannabis plants, you’ll need to put some thought into the process. To dry them outside, you’ll need a warm and dry climate, which can be challenging to guarantee in the fall and winter, when the weather often turns cooler and wetter. This is why many gardeners who cultivate their crops outdoors also acquire home drying equipment.

If you’re used to cultivating cannabis in the great outdoors, you know all about cutting down the plants and sealing up the bulkiest branches and buds in large bags for the trip back to the city. The potent odor of freshly harvested weed can make this a nerve-wracking journey. Drive home safely by adhering to posted speed limits and avoiding any unnecessary attention.

Once you get the buds and branches inside, you can start the drying process. Many cannabis growers, whether they’ve ever grown indoors or not, still invest in a small tent and some drying racks. Some people suspend a piece of cord or a clothes hanger from the ceiling of the grow tent to support the heavier branches. To remove the odor, you’ll need an extraction fan and a carbon filter. It is always extremely dangerous to dry cannabis outdoors without any kind of odor control in areas where people live.

It usually takes the buds about a week to dry out completely. One method for drying involves beginning with a humidity of 60% and gradually lowering it to 55% over the course of several days. When the 7-10 days are up, turn the dehumidifier down to 50 percent to finish drying the buds.

The buds on a branch are ready to be put into curing jars when the branch begins to snap (or nearly snaps). Remember that the larger buds/flowers may take an extra day or two to dry.

Harvested buds that are a vibrant green often lose some of their color and vibrancy when dried. As the curing process continues, you may see various shades of brown, blue, and even red.

Trimming cannabis buds grown outdoors

Some farmers prefer to wait until the buds are dry before they remove the leaves. Buds are typically ready for jarring and curing after they have dried for about a week. Typically, this is when the branches are dry enough to break. Waiting until the buds are dry has the potential downside of trichome loss during the trimming process.

That’s why it’s recommended that growers trim the buds right after harvest. A pair of good scissors (or trimming scissors) and some rubber gloves to protect your fingers are essential. In order to save some hash for a smoke/vape at the end of the harvest party, you may need to scrape the hash off the blades of the scissors every once in a while. Hashish and other cannabis concentrates can be made from the trimmed leaf material by freezing it.

Curing and storing your outdoor cannabis crop

The method for curing and storing cannabis buds grown outside is identical to that used for indoor cannabis harvests. After the cannabis has been properly dried (without being overdried and losing its tasty terpenes), it is ready to be cured.

In order for cannabis buds to last for months or even years, they must undergo a process known as curing, in which the last traces of moisture are slowly removed. During this stage, the aroma can become more concentrated, creating truly remarkable flavors. Terpene profiles not only affect the flavor of your buds, but may also affect the dominant effects of your high.

When cannabis reaches the curing stage, the buds have lost most of their moisture but not all of it. Curing is the last and arguably most crucial step for a cannabis connoisseur. Containers made of glass are frequently used by growers. Inasmuch as the sticky resin has the potential to soften or discolor plastic containers, they are less preferable to use. Carefully trimmed buds are arranged in glass jars with just a centimeter or two of headspace. The containers are locked away and left in the dark.

The jars are then opened once or twice daily to release any trapped moisture. The process is often referred to as “burping” the jars. The standard minimum cure time is two to three weeks. Most experts agree that curing is done after only a couple of months, though some devotees of the craft prefer to wait even longer. In contrast to uncured buds, those used for vaping will not have a ‘chlorophyll’ flavor.

Once your buds have reached their desired level of curing, you may find it convenient to store them in the freezer to maintain their maximum potency. If you’re looking for the best long-term storage options for your buds, you should never keep them in a hot, stuffy place like a loft.

Fine control of the cannabis curing process with Boveda or Integra humidity sachets

You spent money on high-quality cannabis seeds and did your best to cultivate them. When you finally get around to opening those jars, the last thing you want to find is moldy buds from insufficient drying.

Just as you wouldn’t want to open a jar of expensive flowers only to find they smell and taste bad due to excessive drying, your buds should be moist and fragrant. When vaporized or smoked, the result may be unpleasant, giving the impression that the buds are of poor quality or are too old.

When you crack open a jar of buds, you want to be greeted by the sight and aroma of the highest quality buds possible, at full potency, with a pleasant, cured scent and a satisfyingly flavorful taste. Humidity control sachets by Boveda or Integra are one means of accomplishing this.

Whether your buds are too dry or too wet, these sachets will do their job. Products from various manufacturers are available for your choosing. We like the “58% Humidity” sachets from Boveda. The “55% humidity” packs from Integra come highly recommended.

Frequently asked questions about harvesting cannabis

You should try growing cannabis outside if you have never done so before. Growing cannabis outside has much lower production costs than growing it indoors. You can skip buying a grow light and saving money on electricity. Outdoor cultivation has many advantages if you’re concerned about your environmental impact. Growers at the far northern and southern latitudes can still successfully germinate and harvest autoflower seeds outdoors during brief summers.

Do environmental factors affect the cannabis grow season?

Outdoor cannabis cultivation and harvesting can be a lot of fun. Spring and fall/autumn equinoxes are good benchmarks for familiarizing yourself with your local climate. The strains that work best for you depend greatly on your specific environment. It’s up to you to pick out the ideal cannabis seeds for your needs and local environment.

The majority of outdoor cannabis growers cultivate both autoflowering and outdoor feminized photoperiod strains. Even if early autumn storms ruin a photoperiod cannabis harvest, the grower can usually rely on the timely completion of their autoflower plants.

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Daylight hours and outdoor cannabis flowering

To artificially induce bloom, indoor growers use a 12/12 light schedule. Plants begin flowering outdoors, however, well before the 12/12 outdoor light conditions are reached. When a plant is expected to bloom can, of course, differ from one strain to the next. However, most of them only begin blooming when the number of hours of daylight drops to about 14 per day.

At Amsterdam’s latitude in the northern hemisphere, summer daylight hours average 16 or 17 hours. Outdoor cannabis plants in the northern hemisphere typically begin flowering preparations in August, as daylight hours are rapidly decreasing.

Between August 10 and August 25, the daily average of daylight hours begins to decrease from 15 to 14. Outdoor plants usually begin getting ready to bloom around this time. Around the 25th of September, at the latitude of Amsterdam, the sky is completely clear and the sun shines for 12 hours straight. As of around the 25th of October, there are only about 10 hours of daylight left. Typically, most outdoor strains are harvested around this time (or earlier).

Take care when placing your seedlings or plants outside after the average last frost date for your area has passed.

Before planting their cannabis seeds outdoors after the last frost, some growers choose to give them the best possible start by germinating them indoors and nurturing them under indoor lights for a few weeks. Before finally transplanting their cannabis plants outdoors, the best growers will “harden” their seedlings by exposing them to more and more outdoor conditions.

Pellets to deter snails and slugs will be needed to protect the seedlings. For added defense against predators like deer, goats, and rabbits, some cultivators plant thorny brambles around their grow site.

Compost from a garden center can be used to easily improve the soil quality if it is low. Your outdoor cannabis crop will benefit from this. The plants will do the rest of the work for you once they are in their final grow position. It’s enough to keep the thieves and the wild animals away. Water transportation to the grow site may be necessary during drought, but other than that, there won’t be much to do.

Is there an optimal time to harvest your plants?

The ideal situation is when you already know whether you prefer early or late-harvested cannabis. The appearance of trichomes and pistils can be used as indicators of when cannabis is ready to be harvested, and with practice, you’ll become an expert. The outdoor cannabis grower is also mindful of seasonal changes and makes preparations accordingly.

It makes sense to harvest your plants ahead of schedule if winter storms are expected earlier than usual. When the arrival of winter cannot be predicted with any degree of certainty, it may be preferable to grow autoflower seeds indoors rather than rely solely on photoperiod outdoor strains.

There is a school of thought among outdoor cannabis growers that says doing so results in buds with more “kick,” or potency, that result in a more intense and enjoyable high. There is no doubt that growing cannabis outdoors is more cost-effective due to the lack of need for electricity. Locating an outdoor grow space and watching your cannabis seeds develop into robust plants that produce abundant harvests can be a lot of fun, too. However you choose to cultivate your outdoor space, we wish you the best of luck.


Farmers need to have a more foolproof method at their disposal than simply marking their calendars for the expected harvest date. When is the best time to harvest greenhouse-grown cannabis? You should check it out with your unaided eye and a magnifying glass.

When it’s time to harvest cannabis, you’ll know it from the signs in the trichomes, leaves, and pistils. When cannabis is grown in a greenhouse, the quality and quantity of the crop are already guaranteed. Of course, timing your harvest properly also plays a role in how much you gather.