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when to flower cannabis from seed

When to flower cannabis from seed
For growers starting with cannabis clones, generally you should wait a few weeks longer than with seeds. Cannabis clones are more prone to flowering early outdoors than seeds, so you might want to put your clones out in late Spring or early Summer. (What are clones?)

Cannabis Light Schedules: Vegetative Stage vs Flowering Stage

Cannabis plants keep getting bigger and bigger with long days, and start making buds when you give them long nights.

Cannabis is a “photoperiod” plant, which means the amount of light received each day decides when the plant starts flowering or making buds. This article explains how much light a day your photoperiod cannabis plants need to grow and start budding, so you get to a happy harvest day. What about auto-flowering strains?

Vegetative – Seedling or clone leads to Vegetative Stage –
Give 18-24 hours of light a day

Flowering – Flowering (Budding) Stage leads to Harvest –
Give 12 hours light & 12 hours dark each day

Seedling or Clone

While not technically a “stage,” all grows start with cannabis seeds or clones.

Indoors

Plant your seeds or clones when you’re ready to start growing! What are clones? https://www.growweedeasy.com/cloning

Outdoors

Some outdoor growers start their plants indoors to give them a headstart before putting plants outside.

If you’re growing cannabis outdoors with seeds, you should wait until a few weeks after the spring equinox to put your seeds outside. In the northern hemisphere this means seeds go outside in-or-after April, In the southern hemisphere seeds go outside in-or-after October.

For growers starting with cannabis clones, generally you should wait a few weeks longer than with seeds. Cannabis clones are more prone to flowering early outdoors than seeds, so you might want to put your clones out in late Spring or early Summer. (What are clones?)

If you live in a cold climate, you must also wait until after the last frost before putting your plants outside. Freezing temps will kill cannabis plants. Strain choice is very important. Some strains flower earlier than others. For outdoor growers in cold climates, it’s important to make sure you grow a strain that is matched up with your local weather, so that plants are ready for harvest before temperatures drop.

Vegetative Stage

The vegetative stage is one of the most important parts of the life of your cannabis plant.

The vegetative stage is the growing stage of the plant. When in veg, cannabis plants grow bigger and taller, growing only stems and leaves. As a grower, you are able to control the size and shape of your plants in the vegetative stage using simple training methods.

During the entire vegetative stage the plant does not produce buds at all. It only grows stems and leaves. During the vegetative stage plants tend to grow very fast, especially when conditions are right.

What keeps cannabis in the vegetative stage?

Short nights keep cannabis plants in the vegetative stage. You can keep a cannabis plant in the vegetative stage for basically forever as long as the plant continues to get short nights (shorter than 1s-12 hours, depending on the strain).

Cannabis will stay in the vegetative stage as long as the plant gets short nights (less than 11-12 hours of darkness each day)

Whether you’re growing indoors or outdoors, you must make sure your cannabis plants get at least 13 hours of light each day to stay in the vegetative stage. If your plant gets a few long nights, it may start budding before you want.

The plant can receive as much as 24 hours of light a day while in the vegetative stage. Many indoor growers provide 18-24 hours of light a day (known as 18-6 or 24-0 light schedules) during the vegetative stage to encourage faster vegetative growth.

Don’t want to worry about light schedules? For growers that don’t want to pay attention to light schedules, there are auto-flowering strains of cannabis, which will automatically go through their whole life in about 3 months no matter what light schedule is provided. For some growers, an auto-flowering strain may be more simple than a traditional (photoperiod) strain.

Indoors

Most indoor growers provide 18-24 hours of light a day (known as 18-6 or 24-0 light schedules). Giving your cannabis plants more hours of light each day in the flowering stage will encourage faster growth.

Lingo: When a grower provides 18 hours of light a day and 6 hours of darkness, this is commonly known as the 18/6 light schedule. For 24 hours a day, this is referred to as the 24-0 light schedule.

Outdoors

As long as your plant is getting plenty of light a day, your plant will automatically stay in the vegetative stage from late spring until late summer. Every strain is a bit different.

Flowering Stage

Cannabis starts budding when plants get at least 12 hours of uninterrupted darkness each night. After plants start budding, they must continue to get long dark nights until harvest or they may revert back to the vegetative stage.

Indoors

Indoors most growers put their plants on a 12-12 schedule to initiate flowering. Outdoors the plant will naturally start budding in late summer when nights are growing longer and longer as winter approaches. Just make sure plants aren’t exposed to light during their dark period!

What is 12-12 Lighting?

The indoor grower will need to artificially induce flowering/budding in plants by changing the light schedule so the plant receives only 12 hours of light a day, and 12 hours of uninterrupted darkness.

Once the plant is changed over to the flowering (12/12) light schedule, there is generally another 6 weeks-5 months (average 2.5 months) before the plant’s buds are ready for harvest.

Outdoors

Outdoor growers wait until their cannabis plants start naturally flowering on their own, usually after mid-summer when days start getting shorter than 12 hours.

It’s important to make sure plants aren’t exposed to light at night during their dark period, even street lights or spotlights, as this can prevent cannabis plants from flowering properly.

Growing Indoors? Not Sure When To Switch To Flowering?

So indoor growers have a choice to flower their plants whenever they want… When is the best t ime to start flowering your cannabis indoors?

The real answer is that it’s a matter of personal preference and also depends on what end result you’re looking for. There are two major considerations when choosing the right time to switch to 12/12, the age of the plant and the height of the plant:

Age: Some growers feel that a marijuana plant which has been grown from seed will not produce as many buds or have enough resin production if the plant is not given at least 60 days in the vegetative stage to mature before it’s changed over to the flowering stage. This is not true. many growers initiate flowering soon after germinating a seed in order to keep plants small and short. This is often called “12-12 from seed.” Just remember, no matter what you do, a young cannabis plant will not start flowering until it is 2-3 weeks old. Even if you put a seed on a 12-12 schedule from the beginning, it will not start properly budding for about 3 weeks. When growing with cannabis clones, age is not an issue and growers can switch directly to flowering once your clone has established roots. This is because even though a clone may be small, it’s still a ‘mature’ plant since it is made of a piece from a mature plant. Rooted clones tend to grow much faster for the first few weeks than plants grown from seed. In any case, age is not much of an issue, and you should switch your light schedule at the time that best fits your needs.

Height: A general rule is that your marijuana plant will double or triple in size during the flowering stage from the point where you first change over the light schedule to 12/12. Some plants will grow more, some will grow less, but a good rule of thumb is to change your light schedule over to flowering when your plants have reached half of their final desired height. Bending, known as “LST” or “low stress training” can be used to control colas that get too tall. Simply bend too-tall colas down and away from the center of the plant. Some growers will even slightly break or “supercrop” branches to get them to bend at a 90 degree angle. For those growing in a small space, height may be the primary concern. However, there are many techniques available to grow a short, bushy weed plant or basically train your cannabis plant to grow into any shape you want.

Here’s an example of LST to keep a plant short:

In optimal conditions if height and space is not an issue, you would probably want to vegetate your cannabis plant for 60 days or more before switching it over to flowering. This gives your plant plenty of time to grow big (so you get bigger yields), and allows new growers to dial in their grow before plants enter the sensitive flowering stage. In the vegetative stage, it is easy to recover from problems, but problems are a lot more serious in the flowering stage, where mistakes can dramatically hurt your final yields.

Giving cannabis plants more time in the vegetative stage, and taking time to train them to fit your space, will give you the best final yields. However, if space is tight, then it’s better to switch when the plant is half the final desired height, or even to just attempt to flower your cannabis plant straight from seed.

Harvest!

After the vegetative and flowering stage are over, it is time to harvest your plants!

When to flower cannabis from seed
Another sign that your buds are maturing is when the pistils of the flowers change colour. Pistils are small-hair like structures that grow out of the calyxes, and are the reproductive organs of the female cannabis plant. They are the site where pollination occurs—if male pollen were allowed to land there. Pistils appear bright white during the early stage of the grow cycle, and eventually shift to an orange-brown colour.

The Marijuana Cultivation Timeline

GETTING STARTED

Before you get your cannabis cultivation underway, you need to start by crafting a cannabis grow plan based on an understanding of the cannabis lifecycle. You must ask yourself a few simple questions before you rush into growing your precious marijuana.

Firstly, you must decide what kind of weed grower you are and which grow system and cannabis strains will best suit your needs and are optimal for your growing environment. Allow two weeks for research and gathering supplies.

Regardless of your budget and preference for either indoor or outdoor marijuana cultivation, it is absolutely possible to grow great weed from seed to stash. If you have access to clones from a reputable grower and/or club then you can skip straight to vegetative growth.

However, the majority of home growers start a cannabis garden from scratch with seeds. Choose your beans wisely, genetics are the foundation of your grow-op. Cannabis is mostly a dioecious annual plant, but can occasionally display intersex traits, these plants are known as Hermaphrodites and commonly referred to as “hermies”.

Only non-pollinated female plants produce Sinsemilla, so unless you’re a breeder, male plants are useless and must be removed before blooming with regular seeds. Of course, any intersex plants must also be removed immediately to keep your bud high-grade and seed-free.

High-quality feminised seeds are the obvious solution; although you still need to be vigilant because 99% of the time, in optimal care and conditions, they will deliver a high-grade harvest of seedless weed. The average cannabis crop from seed takes a typical ganja farmer between 3-6 months to bring to harvest, so it needs to be dank stash.

Autoflowering varieties must be even more carefully scrutinised to avoid disappointment later. There is literally no time for mistakes with plants that transition to bloom independently of hours of light within weeks and can be cropped within 60-80 days from seed germination total.

Pedigree genetics are just as important with auto’s as they are with photoperiod strains that flower under a standard 12-12 light-dark cycle and spend anywhere between 7-14 weeks in the bloom phase alone.

GERMINATION / 1 to 7 days

Step one is to germinate your carefully selected cannabis seeds. It’s always advisable to get your garden off to a great start so make sure you get germination right. If this stage goes wrong, your crop is all done before it even began. Usually, germination takes between 1-7 days before a tap root emerges.

The paper towel method is a tried and trusted technique, but if you are a newbie or perhaps too heavy handed to gently remove little sprouts without damaging the tiny rootlets, then we recommend our Royal Queen Seeds Starter Kit Feminized. Pop your beans in and play the waiting game for a few days. It doesn’t get much easier to get growing than this.

Sativa leaning strains tend to take a little longer to germinate often 4-7 days. While some Indica strains and vigorous hybrids can take as just a day or two. Outdoors Spring time is naturally the time for seed sowing and cannabis is no different.

SEEDLING STAGE / 2 weeks

Once your cannabis seeds have sprouted they are entering the seedling phase, this is not to be confused with vegetative growth although 18-24 hours of light is common to both stages.

Even if you plan an outdoor crop it doesn’t hurt to get your seedlings strong and healthy indoors before moving them into the wild. Cannabis seedlings can even thrive on a windowsill with decent sunlight.

Seedlings transition to vegetative growth usually between 10-15 days and begin to resemble tiny marijuana plants. The perfect home for cannabis seedlings is a propagator, ideally with 70% RH and temps 20-25°C, under either white CFL lights or LED’s.

Cannabis seeds must be encouraged to develop a vigorous healthy roots. Unless you are planting directly into final containers then small pots with lightly fertilised medium are recommended.

VEGETATIVE GROWTH / 2 to 8 weeks

Vegetative growth is normally associated with a transplant at some point as plants outgrow the starter medium be it a Rockwool block or paper cup filled with soil or coco. Continued development of the root zone and robust branching are the top priorities for the grower. High RH of 50% is ideal and cooler temps 20-24°C can promote more females if growing regular seeds.

Autoflower cultivators have even less time to play with than photoperiod growers as most autos will race into flowering after just 2-3 weeks of vegetative growth. It’s for this reason that many auto growers plant their autoflowering seeds directly into the final container. The clock is ticking with autos from the moment of germination.

Photoperiod strains can be kept in vegetative growth indefinitely so long as 18+ hours of light and suitable conditions prevail. This is what allows indoor growers to keep mother plants for years and why outdoor grower’s plant in springtime. Indoors or outdoors 18+ hours of light facilitates taking cuttings too.

This is the stage to pot up photoperiod plants into final containers, at least a couple weeks before switching to bloom or prior to Summer outdoors.

While the photoperiod strains can be kept in veg weeks or even months to allow for all kinds of pruning and training to boost yield like topping, FIM, LST or even a ScrOG the Auto grower is somewhat limited by time.

FLOWERING / 6 to 12 weeks

At this stage, the focus of the grower and plants switches to the production of buds and the grower is already dreaming of a frosty marijuana harvest in the near future. RH needs to be reduced to 40-50% and temps kept between 20-28°C.

Cannabis plants will first give you an indication of their sex in the early phase of bloom. Typically within the first two weeks of flowering females will develop pistils or “hairs” to confirm their femininity.

If you see “nanners” or anything resembling a cluster of grapes protruding from flowers or anywhere on the stem then you have a male cannabis plant. Should you see both hairs and nanners then you have a hermie to remove right away.

Photoperiod strains are induced to bloom by the hours of light they receive; indoors the grower changes to a 12-12 light-dark cycle to artificially promote flower growth.

Outdoors Mother Nature dictates the grower’s schedule and flowering will only commence in Summer/Autumn as the hours of daylight naturally diminish, making for a longer more gradual flowering period. Weed growers in the Northern hemisphere don’t refer to October as “Croptober” for nothing.

Of course Autoflowering strains don’t follow the rules due to their Ruderalis genetics, so they will begin to bloom in about a month post-germination. Auto’s prefer to stay in 18+ hours of light for flowering and will be more productive on a light-dark cycle that would inhibit photoperiod strains from blooming at all.

Flowering generally lasts 7-10 weeks for indica and hybrid photoperiod cannabis strains, while the more Sativa dominant strains can take 10-14 weeks to fully ripen into primo head stash.

Autos really only flower for 30-45 days with a much more sudden transition into flowering, choosing feminised autos is a wise choice for novices that don’t want a seeded stash.

It’s always best to evaluate if a cannabis plant is ready to harvest by taking a closer look at those resin dripping buds. Using an inexpensive scope to zoom in on those resin heads to make sure they are milky and amber rather than clear removes all the guess work.

Once you confirm you’ve got a ripe marijuana crop on your hands it’s time to break out the trimming scissors and get harvesting. After two weeks slow drying in paper bags or hung up, at room temp and approximately 50% RH, you’ve got a stash.

HARVESTING

Harvesting is the most rewarding part of the cultivation process for many growers. Watching your plants grow over several months is mesmerising, but finally harvesting the fruits of your labour truly is the peak of the experience. The flowering phase of the grow cycle typically lasts between 7–11 weeks, after which it’s time to strip your plants down of their buds. However, you don’t want to do this too early and prevent your flowers from fully maturing. Likewise, you don’t want to wait too long. Timing harvest is a crucial step, and there are multiple signs you should look out for to know when the time is right.

One of the best ways to truly tell if your flowers are ready for harvest is by getting up close and personal with a magnifying device. This visual advantage will enable you to detect minor changes that wouldn’t be noticeable to the naked eye. Some growers choose to use a jewellers loupe, which is essentially a pocket-sized magnifying glass encased in a piece of metal. Others choose to use devices such as digital microscopes, which provide greater detail.

Ultimately, the most important use for your magnifying glass is to detect the progress of your trichomes, and therefore, the proper time to harvest your buds. Trichomes are small mushroom-shaped glands that produce resin which contains the vast majority of cannabinoids and terpenes.

Looking for shifts in trichome appearance is the most accurate way to determine the stage of maturity of your crop. Trichomes are hard to miss and appear as a white frosty substance that covers the buds and sugar leaves. Zooming in on these structures will allow you to know how far along your plants are, and whether they are ready for the chop.

Earlier on in the flowering phase, trichomes will appear translucent, meaning they are still developing and should be left to mature. When approximately 60% of the trichomes develop a milky look, they are ready to harvest. It’s at this stage where they will produce the most significant high. However, some growers wait until up to 90% of trichomes move past this milky look and become amber, as this will cause the buds to develop a more stoning and sedating effect.

Another sign that your buds are maturing is when the pistils of the flowers change colour. Pistils are small-hair like structures that grow out of the calyxes, and are the reproductive organs of the female cannabis plant. They are the site where pollination occurs—if male pollen were allowed to land there. Pistils appear bright white during the early stage of the grow cycle, and eventually shift to an orange-brown colour.

Aside from the buds themselves, another way you can tell your plant is approaching harvest is by examining the colour of the leaves. Provided you haven’t overfed your plants during the final stage of flowering, a yellowing of the leaves will signal that your plant is reaching peak maturity, and that its nutrients are being fully utilised by the buds. By flushing out nutrient salt buildup with pH-balanced water for a couple weeks before harvest, a smoother, more pleasant smoke is guaranteed from each plant.

Now that you know when to start harvesting your buds, it’s time to learn how to trim them.

WET TRIMMING

You can trim your cannabis plants in one of two ways: wet or dry. Both have their own advantages, and each grower will differ in which one they prefer. Wet trimming refers to trimming off the sugar leaves surrounding the buds immediately after harvest while the plant still has a high water content and feels “wet”. This method is the most common, and arguably the easiest, as it doesn’t require a large room to dry out plants beforehand. However, wet trimming is literally sticky business. The resin from the flowers will cover both your hands and your scissors, but there is an upside to this. By scraping the resin from your scissors every now and then, you’ll quickly build up a supply of “scissor hash”, allowing you an early taste of your harvest.

DRY TRIMMING

Dry trimming takes place after your entire stash has been dried, and little water content remains within the buds and leaves. Trimming dry buds is definitely easier on your scissors since they won’t become as inundated by clumps of resin. However, accurately manicuring dry buds can be somewhat of a hassle too, making for a potentially less visually appealing final product. Moreover, dry trimming does require a fair bit of space. Growers usually hang entire branches of buds from a line of string within temperature-controlled rooms to let them air-out until sufficiently dry.

CURING YOUR BUDS

Now that harvesting and trimming are complete, it’s time to cure your flowers. Curing is an essential process that removes the last of the residual water from the buds, minimising the chance of mould and greatly prolonging shelf life. Curing also enhances the taste and quality of the smoke, making for a smooth and potent experience.

If you opted to use the dry trimming method, then your flowers will be ready to cure straight away. If you chose wet trimming, then your flowers will need to be properly dried before you go on to cure them.

To do this, spread them out over some cardboard, newspaper, or, even better, a wire drying rack. Whichever you choose, make sure they are spread out over a large surface area and exposed to as much fresh air as possible. Aim for a steady room temperature of 21°C and a relative humidity of 50% to ensure a longer but gentle drying process to maintain as much flavour as possible.

Now we can move on to curing. For this, you’ll need airtight glass jars to minimise mould from taking hold. Fill each jar so it’s ⅔ full, leaving adequate room for air. This is the perfect environment for excess sugars and chlorophyll to be broken down, a process which is key for those smoother hits of smoke.

For the first two weeks of curing, open each jar once or twice per day and remove each bud, checking for any signs of cobweb-like mould. If you detect anything, remove this bud from the jar and place it in the bin. Opening jars this regularly will also serve to replace the air within the jar, keeping it fresh.

After a few weeks, the need to check your buds as much will reduce; the drier they become, the less chance there is of mould striking. At this stage, you’ll only need to check around twice per week to expose your buds to fresh air. After a few weeks, your buds will be cured; however, some growers choose to go a few weeks further to develop pristine and high-quality flavour. You can smoke-test you buds as the weeks go by to see if the current taste suits your preference.

Royal Queen Seeds produces some of europe’s best cannabis seeds, ensuring hobby growers everywhere have access to the finest marijuana strains around.

Royal Queen Seeds produces some of europe’s best cannabis seeds, ensuring hobby growers everywhere have access to the finest marijuana strains around.

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