Solution: You can find many pre-mixed nutrients from the store which contain nitrogen or you could use nitrate of soda or organic fertilizer which are both good sources of nitrogen. In fact almost all plant nutrients of any kind will include nitrogen. If you haven’t been providing any nutrient to your plants, try supplementing your regular nutrients with a bit more nitrogen and see if the plant starts recovering.
Nitrogen is a mobile nutrient, which means it can move throughout the plant as needed. Cannabis needs nitrogen to keep leaves green and make energy from light. All new leaves get plenty of nitrogen to make them green and help with photosynthesis. The leaves that get the most light are the newest, youngest leaves, so the plant “wants” to give those leaves priority for getting light.
This picture shows a Nitrogen Toxicity
It’s normal for plants to show signs of a nitrogen deficiency as the plant gets close to harvest. This is actually a good thing! Too much nitrogen can actually prevent proper budding, and can reduce the overall taste and smell of your plant. This is why all “bloom” and flowering nutrient formulas are relatively low in nitrogen.
Nitrogen-deficient plants often appear pale or lime-colored. The leaves on this marijuana plant don’t have obvious leaf symptoms like spots or markings, but they are pale all over the whole plant. Almost lime green. The light-colored leaves are a sign the plant needs more Nitrogen (and nutrients in general). On the flip side, plants that are receiving too much Nitrogen turn dark.
Some examples of good one-part Flowering nutrient systems…
As a grower, you’re interested in how much nitrogen to give your plants at what time. The ratio of nitrogen to other nutrients has a huge effect on growth and bud formation.
Sometimes you can get the signs of a cannabis nitrogen deficiency if the pH at the plant root zone is too low, even if the nitrogen is there. This is because when the pH at the roots is not right, your plant roots can’t properly absorb nutrients. If you aren’t sure about your root pH, learn more about pH & growing cannabis plants here.
It’s relatively normal for your cannabis plant’s leaves to start turning yellow towards the end of your flowering cycle as the plant becomes nitrogen deficient while creating buds.
A nitrogen deficiency causes the lower/older leaves of a cannabis plant to start yellowing, wilting, and dropping off on their own. Learn how to fix it.
10 Most Common Reasons for Yellow Leaves
Often plants will have a few yellow leaves by harvest time! This is completely normal and nothing to worry about as long as you’ve ruled out bud rot!
When a shell first cracks, the round leaves inside are actually yellow. They only turn green once the plant starts getting enough light.
You don’t normally see these in pictures because most growers remove them 🙂
When just first 3 sets of leaves turning yellow like the example above (leaves with three fingers or less), it’s not something to worry about as long as the rest of the plant is green, healthy and growing fast!
It can be difficult to diagnose chronic underwatering because problems may look like nutrient deficiencies. Your main clue is that plants perk up every time after you water.
Sometimes Triggered by Old Age / Natural Senescence / Light Deprivation
After your plant has grown a few sets of leaves, it’s very normal for the first few sets of leaves to turn yellow and die, especially if they’re not getting light anymore. You will almost always lose the round cotyledons, the single-finger leaves, and the three-finger leaves (first three sets of leaves).
This vibrant young cannabis plant is healthy and growing over an inch a day
Are your marijuana leaves turning yellow? View the 10 most common reasons this happens (with pictures) and get the solutions!