The mad stretching of the first few weeks will start to slow down in week 3-4, but your cannabis plant will still be growing upward. At this point you’ll actually start to see real buds instead of just hairs (I like to call them “budlets” during this stage) and all the pistils will be white and sticking almost straight out. “Budlets” start forming where buds will be, with white pistils sticking straight out. Your plant is going to start getting a little picky about the environment and nutrients in week 3-4 so it’s important to keep a close eye on your garden.
You need to make sure your plant stays healthy all the way to the end of the flowering stage, and you’ve still got more than a month to go so you don’t want your plant to run into any major health problems now! Be especially aware of leaf symptoms, for example: discolored/yellow leaves, or if your plant starts rapidly losing leaves. It’s completely normal to lose a few leaves at this stage, especially leaves that aren’t getting light (which often look like they may have a nutrient deficiency and then fall off, but it’s just your plant cannibalizing the leaf since it isn’t getting any more light). That being said, overall your entire plant should still be lush and green in week 3-4 while your budlets are forming. As your plant continues through the flowering stage, it’s normal to see a few yellow or discolored leaves near the bottom of the plant, especially in the places where the leaves are no longer getting light. This isn’t anything to worry about if it’s just a few leaves as the plant is putting its energy to the top of the plant and the buds. But it’s not normal for your plant to be yellowing or losing leaves rapidly like this. This is what happens when you give your plants too-high levels of nutrients – the tips of all the leaves actually get “burned.” While a little bit of nutrient burn won’t hurt your plant, it’s important to try to avoid it if you can. Your plant can never recover the parts of the leaves lost to nutrient burn, so if you accidentally give too much nutrients in the future, the burning will start “climbing” up the “fingers” of the leaves.
Cannabis leaves tend to look much less appealing/pretty as more of each leaf gets burned. However, even cannabis plants with severe nutrient burn can produce good bud, so don’t give up if you run into thi problem! Try your best to avoid nutrient burn (burnt leaf tips caused by too-high levels of nutrients), as it can only get worse as the flowering stage continues. When nutrient burn starts getting bad, it can actually start discoloring your sugar leaves (the small single-finger leaves emerging from your buds). If nutrient burn reaches the base of the sugar leaves, you won’t be able to trim it off at harvest so your buds will end up with yellow/brown spots where all the leaves were burned. Nutrient deficiencies can also cause the same problem if left unchecked. 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.