To get good harvests growing weed at home, you need to understand the life cycle of weed plants. Find out just how cannabis grows here! How do you care for your plants through their different stages of growth? Cannabis plants will go through a seedling, vegetative, and flowering stage. Each
How Cannabis Grows: The Life Cycle Of Weed
The life cycle of cannabis plants comprises several stages. You’ll get better results and bigger harvests once you know how these stages work. It will allow you to care for your weed plants in a better way, tailored specifically to the phase your plant is going through. So let’s explore how cannabis grows, shall we? This blog will show you how to keep your weed plants strong and healthy in each stage of their lives!
How Cannabis Grows: From Seed To Harvest
Cannabis is an annual plant, with a life cycle that spans some anywhere between ten weeks and six months. Differences between strains can be quite significant. Ten weeks is a minimum: some strains take over half a year to complete the cycle. The cycle consists of several stages. First, the plant emerges from its seed to become a seedling. Then, your seedling starts to grow to become a big, strong plant. Finally, the flowering stage arrives, in which female plants develop the flower buds that you can harvest.
In nature, the changing of the seasons dictates how cannabis grows. As the days start to get shorter, the plants go from the growth to the flowering stage. When autumn draws near, the time for harvest arrives, as with many other plant species. Autoflowering cannabis seeds are the exception to this rule. They are genetically programmed to proceed to the flowering stage by themselves, regardless of seasonal conditions.
A cannabis plant’s life cycle can be divided into four stages:
- Germination stage;
- Seedling stage;
- Growth or vegetative stage;
- Flowering stage.
Identifying The Stages Of The Cannabis Life Cycle
NOTE: Below, you’ll find descriptions of the overall stages comprising the cannabis life cycle. Please keep in mind that we’re talking biology here: living plants don’t try to fit smoothly into weekly or monthly schedules. Indicas, sativas and hybrids all have their own unique growing paces. These are also affected by situational factors that will differ for weather types, growing locations, and techniques. The images featured are of various strains in different stages and serve as indications only. The point of this text is to paint an overall picture of the four different stages and what to expect as an inexperienced cannabis home grower!
1. Germination Stage
Everything starts with a seed. Moreover, you’ll make the best start with the best cannabis seeds. Looking at weed seeds, the best quick quality check is a close look at their colour and texture. Healthy cannabis seeds feel hard and dry, with light to dark brown colours. When you buy weed seeds, they are still ‘dormant’, or asleep if you will. Packed inside that hard shell is everything the seeds needs to start growing, except one thing: water.
Once you activate your seeds by adding water, they will start to germinate. The protective seed shell bursts open, revealing two growths. One is a tiny root just waiting to dig into the soil; the other is a stem trying to grow upwards. Germination can take anywhere from a few days to two weeks. An easy way to germinate your cannabis seeds is to let them open up on a damp piece of kitchen towel.
Once the root is formed, you can gently put the seed in a flowerpot containing soil. After a few days, the tip of the stem emerges from the ground. After that, two cotyledons or seed lobes appear, ready to catch the first sunlight. From there on, daylight takes over from your weed seed: the plant will now grow by photosynthesis. In the germination stage, your emerging cannabis plant needs 18 hours of sunlight every day.
After this initial stage, your germinated seed turns into a seedling.
2. Seedling Stage (1 to 3 weeks)
At this point, your tiny germinated plant evolves into a seedling over a 2 to 3-week period. The roots start to develop rapidly. They branch outwards underground, after the taproot starts to dig down deeper. The twin cotyledons are now followed by the first two real ‘cannabis leaves’ with their characteristic serrated edges. By now, your seedling should have a fresh, bright green colour. Just like in the previous phase, your plant needs 18 hours of light each day throughout the seedling stage. Be careful not to water seedlings too heavily; the tiny root system doesn’t need much. With its first leaves two leaves catching the light, your seedling is now ready to proceed to the next step in the cannabis life cycle: the growth stage.
3. Growth Or Vegetative Stage (4 to 6 weeks)
Of all the stages involved in how cannabis grows, this one revolves most heavily around growing larger. Bigger plants need more soil to give their root system enough room. That is why you should transplant your plant to a larger pot at the start of the growth phase. You’ll find a grow guide on repotting outdoor cannabis plants here. Snug in their new pots, you give their leaves and roots full freedom to develop.
This is also the stage for topping your plants if you wish to do so. In topping, you cut away the top end of the stem. This makes more energy available for lateral growth (branching out sideways, that is), allowing your plant to develop a greater number of buds.
Speaking of flower buds: even though the flowering stage follows the current growth stage, you can start to spot the first signs of male or female plants when your plant is about six weeks old. If you’re not working with feminized seeds, you’ll need to remove any male plants ASAP. If you don’t, you’ll get in trouble in the flowering stage, because males will pollinate females, making them produce new seeds instead of bigger flower buds. Read how to spot the differences between male, female, and hermaphrodite cannabis plants here.
Throughout the growth stage, your plant still needs 18 hours of light every day. It will also grow more thirsty as its root system matures. Keep watering copiously, but don’t overdo it. Check the soil moisture level to prevent the onset of fungi and rot. Beyond that, let your plant do the work. Make sure it stays comfortable, with enough-but-not-too-much water and nutrients, and enjoy watching how cannabis grows. Before long, the flowering stage will arrive.
4. Flowering Stage (7 to 9 weeks)
Although differences between strains are huge, after about two to four months, cannabis plants enter the flowering stage. At this point, female plants start to develop their calyxes or flower buds. The white ‘hairs’ on the buds are pistils, revealing your plant as feminine. These flower buds will soon be full of glistening trichomes. Trichomes are the tiny glands containing the resin that carries the most cannabinoids like THC and CBD. They also carry the terpenes that give your plant its unique scent, taste, and subtle effects. This is the fruit of your labour; the result you’ve been investing all your time and effort in.
If your plants are growing outside, this stage is initiated by the shortening of the days after the summer solstice has passed. At this stage, the cannabis plants only require 12 hours of light each day. As noted above, autoflowers don’t care about light; they’ll start flowering when they feel they’re ready. In the flowering stage, your weed plant needs plenty of water, as well as an ample supply of nutrients. Many growers add extra nutrition in the flowering phase. Be careful not to give too much, because that will ‘burn’ your leaves and harm your grow.
If you’re not using feminized seeds, you need to remove all male plants at the onset of the flowering stage. If you don’t, males will fertilize your female plants and cause them to produce seeds instead of the big fat buds you’re after. As mentioned, you can see the early signs around six weeks into the plant’s life cycle, but the onset of flowering is your last chance to remove any males or hermaphrodites before they ruin your females.
During flowering, watch out for fungi or pests harassing your plants. Rainy weather is something to watch out for in outdoor grows. For indoor growers, ventilation is key in preventing fungi and other unwelcome guests, as is a clean growing environment. It would be a shame if your harvest was to fail this close to the finish line.
One more tip: flowering weed plants smell of – you guessed it – weed. This is the stage at which nosy neighbours or ‘crop snatchers’ can become a problem. Take some time to think about how you will deal with these issues before you start growing.
How Cannabis Grows: After The Flowering Stage, It’s Harvest Time!
Many rookie growers find it hard to determine the moment at which their weed plant is ready to harvest. We know it’s difficult to stay patient and wait, but hang on – your crop yields will only get better! You can see when a plant is nearly ready to harvest once the trichomes go from transparent to milky white and opaque. The pistils of the flower are another tell-tale signal. By the time these pistils start to curl inwards towards the bud and turn golden brown, it’s almost harvest time.
Once you start to harvest, you may think you’re all done, but wait! You’ll still need to trim your buds to remove any plant material without THC or CBD. In addition, harvested buds need to dry and then cure to attain perfect taste and potency. It’s a bit like good wine or cheese – it takes time. We will discuss these steps in separate blogs. For now, at least you know how cannabis grows. Fancy starting your very own grow adventure right now? Click the link below to find the ideal cannabis strain for your situation!
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The germination of cannabis seeds is illegal in most countries. Amsterdam Genetics cannabis seeds are exclusively sold as collectable souvenirs to customers living in countries where the cultivation of cannabis is illegal. All information on this website is intended for educational purposes only and is not meant to incentivize people to engage in illegal activities.
When Growing Weed Indoors:
From Seedling to Flowering
How do you care for your plants through their different stages of growth? Cannabis plants will go through a seedling, vegetative, and flowering stage. Each stage is unique, so it is crucial to understand each part of the growth cycle to produce healthy plants.
Your cannabis seeds have successfully sprouted, time to be planted in your chosen medium. Just a few millimeters below the surface of your medium. Your little plant babies are delicate and easily damaged. So handle them with care. Plant them with the roots facing downwards as an easy way to give them stability.
The Seedling Stage
In this stage, cannabis in the seedling stage does not require intense lighting setup. Compact fluorescent lights or LEDs will work. The optimal seedling light schedule is 18 hours on and six hours off.
Remember seedlings are tiny and fragile, so you should water them accordingly. Major Rookie move is overwatering your seedlings that can wreak havoc on your whole operation. The temperature of the room you have set up to grow stays between 68 and 77 degrees known as the sweet spot. Important at this stage is humidity and some growers may use humidity domes to keep the seedlings in their comfort zone.
Seedlings may be managed in small containers later transplant them to their permanent container during the vegetative stage is common. This stage normally last about two to three weeks.
This stage is where growing gets exciting. The vegetative stage is when the plants have developed strong roots and leaves. If you are transplanting them into their bigger containers be careful. In this stage you will see rapid growth.
In this plant growth cycle you may see a series where new leaves pop up frequently, usually stopping at around 10 leaves. Branches may even start to develop, and expand in new directions. Space your plants according to their expected growth depending on if you choose indica, sativa, or hybrid. The vegetative stage, is where you can begin to train your plants by pinching or topping them, which typically ends up increasing your yields.
The more sunlight your plants have they will stay in the vegetative stage longer. Growing indoors allows you complete control on how long they stay in this stage. If you want them to stay in the vegetative stage and not flower, you can keep them in the same light cycle as the seedling stage (18 hours on, six hours off). If space is an issue, be careful how long you keep your plants in the vegetative stage. The longer they are kept without flowering, the larger the plants will become. Typically plants stay in this stage from three to 16 weeks.
Keep the Males Away
Very Important stage when moving to the flowering stage, be sure to determine if you have any male plants in the mix. If you do; you’ll want to throw them out because they will try to pollinate your plants, forcing the females to produce seeds. You’re trying to get them to flower, not go to seed.
Female plants have pointy green calyxes, tear-shaped flowers that grow little white pistils.
Males will not have this characteristic and instead will have small pockets filled with pollen.
Make sure you separate any males from your bunch before the pockets of pollen burst.
Feminized cannabis seeds should be used if you don’t want to deal with separating the male plants out.
If you have made it this far pat yourself on the back. The final stage begins in flowering when you cut back on the light, reducing it to around 10-12 hours per day. When you adjust the light, plants will sometimes have a growth spurt as they anticipate the coming of winter. Be sure to have enough space.
When your plants begin to develop resiny buds. It is going to require more nutrients. It’s important to not abruptly make changes to your schedule, but instead, ease from using growing to flowering nutrients over the course of a week or so.
Normally around the third or fourth week of flowering, your plants will stop growing altogether. Now they can focus all of their energy on making dense, aromatic buds loaded with trichomes.
Harvest time will vary, but somewhere between week six and eight is a good time to prepare. Determining harvest time by looking at the pistils and trichomes on your plants.
(Don’t rely on number of weeks to know when you should harvest, too many factors are at play). The pistils, or tiny hairs, should change from white to yellow until they are finally brown. This will vary slightly depending on the strain you are growing. A heavily-magnified item such as a jeweler’s loupe can be used to zoom in to the tiny appendages of your trichomes. The color is extremely important!
Clear trichomes mean the plant is not ready.
Milky means they are at peak THC levels.
Amber means they are beginning to decrease in THC levels.
Tips For Successful Indoor Growth
Follow directions as labeled on your nutrients and check for specific variations in growth for the strain you plan to harvest. Don’t prune your plants after a few weeks into the flowering stage as it can throw off their hormonal processes. It’s important to stick to your light regimen precisely, as exposing your plants to light during their typical cycle of darkness can mess up the flowering stage. If you can’t stop yourself from peeking at your plants during their “night”, you’re going to hurt your yield.
Interested in Growing Legal Medical Marijuana?
We offer the standard low $150 Medical Marijuana card in Missouri. Check out our Medical Marijuana Grower’s page to meet with our Doctor about getting a card.