So you’ve gotten in the game of growing marijuana and you’ve been successful so far. You’ve gotten your seedlings to take root, you’ve grown them through the vegetative stage to a sizeable plant. And you’ve now flipped to 12/12 light cycle to finish the process.
The thing about growing weed when you’ve never done it before is that each week is like a mystery. You’re not quite sure what to expect. And when something new develops, it’s this giant surprise that has you scrambling, trying to figure out what to do next.
This happens whether it’s discovering that you have a problem, like powdery mildew, or allowing your plant to grow tall and skinny and then realizing that’s why you have next to no yield.
Learning how to Grow Weed is a practice in Trial & Error
The first few rounds of growing are hard. It’s truly trial and error. But if you can have a guide, such as this blog, that prescribes a set of general guidelines and expectations, the journey is so much more fun. That’s what happens when you remove unnecessary bouts of stress and self-doubt.
So let’s jump into some of the specifics on what to expect when you start the flowering cycle.
We’ve covered the foundational concepts in our article Understanding the Flowering Period of Cannabis. And that article will absolutely get you a clear understanding of the two photoperiods.
But once you start growing, you quickly realize how theory alone is not enough to get you through solving many of the day to day situations.
A big part of the mystery is just knowing what to expect week to week. So that is why we have created a Week-By-Week Guide, with photos and video, to show specifically what the plants actually look like each week.
In this article, let’s specifically answer the question of when to start expecting bud after flipping to the 12/12 light cycle.
What is the 12/12 light cycle for marijuana growth?
The 12/12 light cycle refers to 12 hours on, 12 hours off, with regard to indoor lighting. This light cycle is necessary to trigger the flowering stage of cannabis. But first, let’s back up and re-examine the light cycle used to get here.
To quickly summarize how to grow marijuana, after you sprout your seed, you must grow it up through what is known as the Vegetative stage. This phase mimics the summer where the is more than 15 hours of sunlight per day. The days are long and the nights are short.
When growing indoors, that means you keep the lights on longer than you keep them off. This causes the plant to grow, but prevents it from blooming.
The reason you do not want the plant to bloom immediately, and produce bud, is that you want the plant to be a certain size, capable of actually producing big buds.
So you keep the lights on for 18 hours a day, off 6 hours, to speed up the growth and get your plant to the right size. This usually takes four to eight weeks, depending on how big you want your plant to get.
When you are ready to start producing bud, you must then switch the light cycle. If you are wondering when should you stop the vegetative light cycle and switch to a 12/12 flowering light cycle, we have written two articles on the subject:
Making the Switch from a Vegetative light cycle to a Flowering Light Cycle
Once you’ve made the switch to a 12/12 light cycle, you will not immediately see buds. Do not worry. Nothing is wrong. Your plant will need some time to adjust to the new cycle before it will begin producing flowers (buds).
In this article, we will tackle the issue of when you can expect to start seeing buds, how big they should be at each stage, and how long to flower your plants. Once you know what to expect and when to expect it, flowering cannabis becomes less a guessing game of mystery and self-doubt and more of what it should be, an enjoyable ride with a clear destination.
Marijuana Plants will not produce buds during the first few weeks of the 12/12 light cycle
If you have just switched to the 12 on, 12 off light cycle, do not expect to see any bud sites during the first couple of weeks. During Week 1 and Week 2, the plants are simply adjusting the additional darkness they are receiving. This extra amount of darkness allows them to recover, which sends them through an intense growth spurt that lasts several weeks. This growth spurt is known as the post-vegetative stretch.
During the first two weeks of the flowering light cycle, your plants will look like they are still in veg, except they will be growing out of control. Check out our resources on managing the stretch during this time, as taking control of the plant’s chaotic growth is absolutely critical to getting good results later in the flowering stage.
Marijuana Plants will begin to form pre-flower bud sites in Week 3
If you check out our Week-by-Week Guide to Flowering Cannabis Indoors, then you will see the emergence of pre-flower bud sites in Week 3. These sites will sprout long white pistils (i.e. the “hairs” you are used to seeing).
This photo shows the development of the bud sites during Week 4
The plants will see be deep into the post-vegetative stretch, still resembling stretching veg plants. But these bud sites let you know that the plant is maturing and making its way through the flowering phase.
Marijuana Plants will show more advanced development in Week 5 of Flowering
It is in Week 5 that your plants will really begin to show developed bud sites. At this point, the vegetative growth has ceased and only bud development growth is taking place.
This maturity growth will only increase as you progress through flower. During Week 6, the aroma will be so strong and the plants will be looking so beautiful. During Weeks 7 and 8, you will want to get your camera out to capture the beauty and elegance of your live cannabis plants.
Conclusion
So in summary, you will not see buds for the first three weeks. During the third week, pre-flower sites will emerge, but will not fill in until Week 4. You will notice distinct development in Week 5 that will only increase as the plants progress through the remainder of flower.
FAQs
When you're ready for plants to start the flowering stage, change your lights to a 12/12 cycle (12 hours with the light on and 12 hours with it off ). You will see signs of flowering in 1-3 weeks. On average plants will be ready to harvest after 8-11 weeks of flowering.
How long does it take to switch to flower? ›
It's usually divided into weeks or three stages. The flowering period for Indica strains is typically around 8 weeks, but it may take up to 10 weeks. Sativa strains may take up to 10-12 weeks. Typically, hybrid strains will take up to 6-10 weeks to fully develop.
When should I flip my plants to 12 12? ›
Height of plant: Depending on the strain, plants will generally double in size during flowering. So, if 'room' height is limited, the switch to 12/12 will need to be done no later than when the plant has reached 50% of the 'available' height (remember to consider the minimum gap distance between lamp and foliage).
How long does it take to grow 12 12 from seed? ›
The “12 /12 from seed” technique aims to initiate the flowering stage immediately after germination. Learn about cannabis light schedules. This creates small “bud stick” plants that are typically ready to harvest in 3-4 months.
How many weeks do you flip to flower? ›
Growers can switch to the flowering stage as soon as the clone has established a solid root system. In optimal conditions, plants should be kept in their vegetative stage for approximately 60 days. This time period should give the plant the opportunity to maximise yield and acclimatise to growing conditions.
What is considered week 1 of flowering? ›
Week one is the transition stage between pre-flowering and full flowering when your plant switches from growing tall to producing buds. During this transition, some strains will double in height from what they were a week earlier. Because of this rapid growth, week one is commonly known as “the stretch”.
Can you speed up the flowering stage? ›
If plants have a short-day response, then shortening the days by totally excluding light from the plants for 12 hours per day will accelerate flowering.
What are the first signs of flowering? ›
Signs of flowering: A week-by-week overview
The first three weeks are pre-flowering, the first sign of the flowering stage. Your plant starts showing signs of sex, rounds off its vegetative growth, and gets to cola production. After that, flowers emerge, fatten, develop a strong smell, and start enticing your senses.
How many nodes should I have before flowering? ›
It is recommended that you wait until your plants have at least four nodes before topping them, and most growers recommend topping the plant above the sixth node. Nodes are the part of a plant that connects new stem offshoots with older growth, which can form a branch, a leaf, or in the case of cannabis plants, a bud.
What week Do buds start forming? ›
Weeks 3-4 – Buds form
During this period, the growth spurt will start to slow down. Your weed plant should be about 50% bigger than a mere three weeks ago. All energy goes into forming the budlets instead.
The buds aren't really big, but they're starting to produce a lot of resin. The buds have to get hard and heavy over the next weeks. They won't get much larger in size, but will become heavier and of better quality.
Do buds grow at night? ›
12 or more hours of darkness is the biological trigger for photoperiod cannabis to bloom. Outdoors, as the nights grow longer incrementally from the summer solstice onward, some strains can even begin flowering when receiving 14 hours of sunlight.
Does 12/12 require flowering? ›
What is the 12/12 light cycle for marijuana growth? The 12/12 light cycle refers to 12 hours on, 12 hours off, with regard to indoor lighting. This light cycle is necessary to trigger the flowering stage of cannabis.
Will 12 year old seeds germinate? ›
Yes! Even seeds that are thousands of years old can germinate. But proper pre-treatment is essential, and the older the seed, the less energy it has left in storage. Seeds from annual plants aren't often designed to last many years, part of what makes the germination process so tricky.
What can I plant in a 12 by 12 garden? ›
A whole 12-inch square is required for each broccoli, cabbage, cauliflower, corn, eggplant, muskmelon and pepper plant.
What does week 4 of flowering look like? ›
At week 4 of the flowering stage, your cannabis plants will likely have stopped growing altogether and are now spending all their energy on growing buds. There will still be white hairs sticking out from the buds, but the buds themselves will become bigger and fatter with each day.
What should week 3 of flowering look like? ›
More growth and stretching of the plants in Week 3
You will notice continued growth and stretching. You can see in the video how bushy everything has become. This rapid, almost non-stop growth is all a sign of the post-vegetative stretch that these plants go through after switching to the 12/12 light cycle.
Does longer veg time increase yield? ›
The longer you keep your plants in the vegetative stage, the bigger your plant will be, resulting in bigger yields from plants that were vegetated longer.
Do buds still grow in week 6? ›
If you grow strains with an average flowering time, the majority of bud development will occur by the 6th week of bloom. In the last two weeks, the buds will mostly be ripening and not really growing much more in size. At this point, the previously white pistils on the buds will now slowly turn amber-brown.
How many hours of darkness does flowering start? ›
Flowering starts after more than 7 hours of dark period
Instead of splitting off leaves, the plant starts producing flowers. After two cycles of a sufficient enough dark period, the plant fully enters the generative phase.
Day length may also have flower-inhibiting effects. For example, if a single leaf of K. blossfeldiana is exposed to short days and the remainder of the plant is maintained under long days, the presence of long-day leaves between the short-day leaf and the shoot apex prevents flowering.
How do you force the flowering stage? ›
If you're growing a handful of plants on a balcony or terrace and don't have extreme temperatures and harsh rains to worry about, a simple wooden or PVC frame fitted with a light-proof tarp might be all you need; simply pop your plants under the tarp at night and give them a full 12 hours of uninterrupted darkness to ...
How do you stimulate flowering? ›
How to make a flower bloom more (and longer)
- Choose long-blooming perennials.
- Deadhead your flowers for more (and longer) blooms.
- Fertilize your plants for extended blooms.
- Visit the garden center multiple times a year.
- Plant multiple varieties of your favorite perennials.
- Wrapping Up.
Biologists have discovered that the air pollutant nitric oxide acts as a plant hormone to delay flowering in plants. The scientists discovered that while plants produce their own internal nitric oxide to regulate flowering, they are also influenced by external concentrations of the chemical.
What does a flowering rush look like? ›
Flowers comprise of three pink petals and three sepals arranged in clusters or umbels (umbrella shaped) on a flower stalk. Flowers typically bloom in June through early fall. Small buds that form in the clusters of flowers can disperse and grow into new plants.
Which can induce early flowering? ›
Drought stress induces early flowering under LD conditions and delays flowering under SD conditions in Col-0 (but not in Ler) of Arabidopsis (Riboni et al., 2013). Expression of the flowering gene FLOWERING LOCUS T (FT) is involved in both stress-induced flowering and photoperiodic flowering, as discussed below.
What stage do buds grow the most? ›
When do buds grow the most? Buds typically grow the most toward the end of the flowering life cycle. You probably won't notice much budding out at the beginning of the flowering stage, and it will slow down toward the end of the cycle, when buds become fully formed.
Do you prune above a node? ›
The node is where leaves, buds and shoots emerge from the stem. You should always cut just above a node, as this prevents 'die back' and therefore disease. Also, by cutting above a node you can manipulate new stems, leaves or flowers to form in a desired direction, as nodes form on different sides of a stem.
When should I trim off fan leaves? ›
Usually, growers trim the fan leaves weeks before harvest, which is a period that leads to senescence, a phase in the plant cycle when the larger leaves start fading away. It is safe to start removing these dying leaves and continue until harvest.
What week Do buds dense up? ›
Thicker, more compact, and heavier buds are what we're looking for. Usually, you can see the most bud development during weeks 5-7 and it can be disappointing to see the light, airy buds; they are not what we imagine when we first start growing.
You can remove fan leaves during flowering in much the same way you do during veg. Prune away large leaves that are overshadowing bud sites, as well as dead or dying fan leaves. One thing to keep in mind is that you should prune in intervals, giving at least a couple weeks between each session.
Do buds get bigger in last week? ›
The last three weeks is when your buds can actually gain the most weight – that is if you feed them Overdrive®. After your peak bloom phase, your plants enter their late bloom phase (the precise timing and length of which depends on the plant strain you're growing).
Do buds grow after week 5? ›
Changes from Week 4 to Week 5
The biggest changes that you will witness in the fifth week of your flowering cycle is not so much in total plant growth (as in Week 4) but in the maturity of the buds. It is in Week 5 that the buds really begin to fill out. Even more growth will occur in Week 6 and beyond.
What week Do pistils turn orange? ›
Pistils are a great indicator of how your female cannabis plants are progressing. With the onset of a 12/12 light cycle, the pistils will be completely white. Somewhere around week 4-6, midway through flowering, is when the first orange, red and/or pink colours begin to emerge and proliferate.
Do buds need to dry in dark? ›
The ideal drying room must be dark, as light can damage the THC in your buds. While it does not hurt to have a light source inside to check on the progress of your buds, you should keep it off most of the time, and block all other passages of light that can enter the room.
How do you grow big buds fast? ›
Feeding a plant nitrogen while it is vegging creates a healthy, vibrant plant at a young age that will grow rapidly, which leads to increased yields. Once your plant switches to flowering, decrease your nitrogen levels and increase phosphorus levels to help the buds fully develop and become dense.
How do I grow bigger fatter buds? ›
You want to use top-shelf genetics if you want massive buds. You can grow various strains from either clones or seeds. Use bloom boosters – When you give your plant a proven bloom booster, you're giving it extra “supplements” that help it grow bigger, denser, heavier and more potent buds.
Do flowers start 12 12? ›
Counting from the day you flip to 12/12
After all, this is the point at which the plant gets the cue to start flowering, so it's a simple point of departure.
Can you put an auto Flower on 12 and 12? ›
Can you grow autoflowers on a 12/12 light cycle from seed to bud? Yes, you can grow auto autoflowering plants under a 12/12 light schedule from start to finish.
What does week 3 of flowering look like? ›
Week 3. Your cannabis plants have still not entirely stopped growing and will now be about 50% bigger than what they were just three weeks earlier. Although still stretching a bit, the stretch will now gradually slow down and soon come to a complete halt.
Technically speaking, autoflowers don't need darkness because the Ruderalis is accustomed to 24 hours of daylight at times in the wild, depending on the season. They can be grown in any light cycle as long as the conditions are favorable in terms of temperature.
How many times can you top an auto flower? ›
You can top the plant once, or repeatedly, and allow as much time as you wish for the plant to recover and grow. Plants grown from autoflower seeds can be topped, but the high stress training technique will cost your autoflower several days to recover from the process.
How long does an auto flower bud for? ›
Autoflower cannabis average time from seed to harvest
With 5-6 weeks of vegetative growth and around 9 weeks of bloom it can take 15 weeks or more for a feminised strain to reach harvest.
