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light for cannabis seedlings

Light for cannabis seedlings
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.
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.
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.
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.
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.
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:
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).
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.
What do I need to know about light cycles and flowering my marijuana plants? Plants keep getting bigger and bigger with long days, and start making buds when you give them long nights.
Light for cannabis seedlings
Mastering the delicate seedling stage is crucial to grow strong and healthy cannabis plants. Read this blog for further information on how to cultivate cannabis from seed to seedling.
Before germinating our cannabis seeds, we make up our mind about containers and soil, assuming most rookies prefer soil due to simplicity. At this point, we already need to differentiate between autoflowering – and feminized/regular seeds.
Growers of autoflowering varieties will get best results when they plant the seed directly into the final pot, and need to pay very close attention to seedlings for the first three weeks. Mistakes in the vegetation period of autoflowering strains have fatal consequences, meaning low yields. Depending on the strain and growing method, pot sizes ranging from 5-15 liter can be used. The size of the pot will have an influence on the size of your plants, on yields, and on the frequency you water your plants. Tip: Airpots allow more oxygen to get to the root system and will boost vitality and final yields.
Aim for humidity levels of approximately 70%. Small propagators can be an option if you start in very small containers but autoflowering growers planting in final pots need to monitor, and eventually raise, the humidity inside the grow room.
There are basically two different techniques that are commonly used to germinate cannabis seeds.
Feminized- and regular cannabis varieties give growers the possibility do decide when the vegetation period ends, and the flowering period starts. This is why transplanting “feminized” seedlings is not such a big concern, in contrast to autoflowering strains. When a few days are lost due to stress recovery of the plant, growers simply increase the time-span of the vegetation period and compensates the loss of growth. Internet forums and grow reports can help to get you an idea what works best in terms of pot size(s) matching your setup.
High quality organic soil that is “light” when it comes to pre-added nutrition works best.
After seeds have germinated, it’s time to plant them into the pots. Plant the seeds just 3-5 millimeters below the surface of the earth, ideally with the tiny root facing downwards. This can help to avoid time-loss and seeds don’t have to figure out how gravity works.
Simply drop your seeds into a glass of drinking water and wait 24-48 hours until seeds have cracked. Wait until you see the first few millimeters of the root, and make sure water temperatures are between 20-25 °C. Place your cup somewhere light doesn’t reach it.
Are you concerned about the delicate seedling stage when growing cannabis? Don’t be! Follow these 3 steps and cultivate healthy seedlings.