This doesn’t necessarily affect the potency but buds don’t look as good as they could have. So to grow bud you’re proud of, you’ll want to be aware of avoiding nutrient burn from the beginning. Since your plant isn’t really growing many more leaves, you need to really care for the ones it has left.
If they haven’t already, your plants may start to smell! Some strains like Blue Mystic and Northern Light are known for having relatively low smells, but many strains can start getting pungent quickly! Your budlets are fattening and soon you will have buds with substance! They will still have nearly all white pistils sticking straight up in every direction, but the buds themselves will be getting fatter every day. By weeks 4-6, the stretch is almost over and you no longer need to pay attention to training your plant. Instead of trying to keep the colas down, from now on you’re doing the opposite – trying to hold any buds up if they start getting too heavy for your plant! If you’re having trouble fitting your plant in your space within a safe distance from your light, your training options can start looking very grim.
If your plant has grown into the light, you may have to consider last-resort solutions like supercropping (a high-stress training technique of forcing stems to bend at a 90° angle) which you normally should never do this late in the flowering stage. Since you don’t get many more new leaves, you need to think of your remaining leaves as armor – insurance against any nutrient or leaf problems. Although you don’t want an excessively leafy plant, and strategic defoliation (for advanced growers) can be helpful to expose bud sites, it’s important to make sure that you let your plant keep enough leaf coverage to power the growth of buds. It may need a little extra help if something happens! Although defoliation may be used to expose buds sites, make sure your plant still has enough leaves (“armor”) to last until the end of the flowering stage to power the growth of buds, and as insurance against any possible nutrient or leaf problems. Although most of the pistils will probably still be mostly white by the end of week 6, the buds are getting bigger and denser every day! From now on your plant won’t be making any new leaves or stems. It has completely switched gears away from vegetative growth and all its energy will be focused on growing buds from now until harvest. It’s normal for some of the bottom leaves to begin to turn yellow as the plant continues to put its energy in the leaves and buds getting the most direct light, though the plant should still be mostly green from top to bottom even in week 6-8. At this point, your plant may start getting much more picky and sensitive to nutrient problems, including those caused by incorrect pH at the roots. Now is not the time to slack off on caring for your plants! If your leaves are already turning yellow in week 6-8 it’s too early! Early leaf yellowing is likely caused by either a nutrient problem or light burn (which are both much more common in marijuanas flowering stage). React quickly to problems so you don’t hurt your yields! Another common problem to watch out for at this stage: if you see a whole new bud or “spire” emerging out of the side of an old bud that’s already developed, it’s usually a sign of heat or light damage. “Foxtailing” like this is caused by too much heat or light – it’s not normal bud growth! If you see this it means you need to control your temperature and light levels to prevent further damage! From now until harvest it’s extra important to avoid too-high levels of light or heat because (in addition to foxtailing) this can discolor/bleach/burn your buds and may even “evaporate” away some of the THC / potency. If things are going well, your buds should be really hitting their stride at this point. They will grow in size significantly over the next few weeks! To make sure things go smoothly until harvest, treat your plant like a movie star and attend to its every need!
Very few strains of cannabis are ready to be harvested before week 8, but now we’re at to the point where some short strains are getting close to being harvest-ready! Many growers do a final flush, which involves giving only plain water to your plants (for a few days up to a few weeks) before harvest. Once you’ve reached week 8, buds are fattening quickly. Trichomes and pistils are maturing, though new pistils may continue to develop on the buds as they grow. You are basically just maintaining your plant until harvest. Different strains are ready at different times, but from now on you’re going to pretty much treat them all the same. Keep a close eye on the buds, pistils and trichomes as a whole to help you figure out the best time to harvest to get the effects you are looking for. Try taking a picture of the bud in the dark with your camera flash on. Just around 8-10 weeks is when you get to see the buds in their full glory.
It’s also when the smell of cannabis often starts to get overpowering ! Your plants are probably STINKING up everything around them! At this point it’s completely normal for your plant leaves to start yellowing, sometimes rapidly. As long as the yellowing isn’t affecting your buds and you’re very close to harvest then it’s completely normal.