A good rule of thumb is that if you’re sprouting seeds that are sativas, you should optimally give them around 60 to 90 days to grow from seed to allow sufficient growth before inducing flower. In my experience this allows for larger plants that tend to be more predictable and produce larger flowers that will mature in a timely manner.
Some training can help to improve yields once your sativa variety is growing, but training is best done before flowering has been induced either from climatic seasonal change or a supplemental light regimen. In my experience, higher yields can be achieved from sativas if training is kept to only the vegetative stage and is stopped once flowering is induced. Bending sativas is the least intrusive training method which allows plant growth regulators called auxins to be distributed throughout the growing plant and not just to its floral tips. Another method which is employed by skilled and experienced cultivators of Sativas is by topping or pinching. This method allows the cultivator to regulate size of plants and encourages lateral and bushy growth if performed correctly. This method is the most intrusive method of training and can severely damage your growing sativa which can lead to poor yields and delay maturation of floral sativa clusters.
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