Late Flowering Yellowing

[OlderStoner]

I have a sativa female that's in week 8 of flowering. Her leaves show signs of nute burn but the buds are huge and getting fatter. So I cut the nutes way down 2 weeks ago and now I stopped nutes altogether. She's been yellowing up as expected. I was always real stingy with the nutes because I've burned plants in the past. I guess I don't get how at such low usesge of the nutes then why did I still get leaves with brown tips?

 

[Emilya Green]

Brown tips don't always mean burning. A potassium deficiency for example, steals the nutrient from the tips and margins of the leaves where it is stored. Potassium is taken from the middle of the leaves and magnesium and calcium deficiencies leave random spots on the leaves and also wipe out large portions of the tips of the leaves.

I suspect from your description that you are starving your sativas based on your assumption that you were overfeeding and that the damage you are seeing is a result of that starvation, not burning. Some pictures of what you have going would be very helpful in completing this diagnosis.

 

[OlderStoner]

Okay, forgive me for being bored with Cabin Fever due to Covid-19 shutdown, this is probably too wordy a post but here goes.

In the words of that inimitable philosopher of life, "Vinny Barbarino" on the old "Welcome Back Cotter" series, "I'm so confused!" Do I have nute burn or a case of too little nutes like Emilya references above. Not that I doubt her credentials, she is well informed and helpful.

So here's the scoop. This beautiful female is estimated to be 20 weeks from a seed sprouted in some wet paper towels. I can only estimate because I didn't record the exact date, I know it was sometime in mid to late April 2020. She was topped early on so she has twin colas of substantial length and girth. Not to mention the dozens of other buds she's sporting, and quite well as far as most of my previous grows have gone. Before I describe the nute burn issue further let me interject here that she came from a seed that I got by pollinating during previous grows. I tried to be particular but let's just call her a "Heinz 57" variety. Her great grandparents were White Widow, then I crossed in some Strawberry Blue, some Skunk Haze and some Cotton Candy. These strains were all involved in her evolution. As you see, she looks healthy and green but most of the rest of the leaves on this mama are yellowing as one would expect in late flowering.

The buds are looking top notch. Lots of cloudy trichomes. I checked closely this morning and if there are any amber ones in there I just can't see them yet. The red pistil hairs are numerous but I would not estimate them to be the 75% I'm looking for so she's got at least 2-3 weeks more.

The original soil was a 50-50 mix of FF Ocean Forest with some home-made organic compost I get by tossing all my uneaten salads and fruits, banana peels, etc... into a pile in my backyard. I put all that in a big plastic pot and augmented the mix with natural organic Plantone fertilizer and some dried blood. I was liberal in adding these to the soil as they are organic and one would think there is no danger of burning the plant with it. I watered her lightly to begin with but in this heat wave there have been times I poured 2-3 gallons of water on here at a time and nothing leaked out the bottom. The soil is airy but you can guess her root ball is extensive and she would drink up all of that properly ph'ed (6.5) water. About every 3rd watering I mixed in a little more of the Plantone, some FF Tiger Bloom and FF Grow Big. And with the FF nutes I used only 1/2 cap full to a gallon of water. That was enough to change the color of the water slightly but nothing anywhere near the full dose FF recommends.

Once she went into flowering I cut back to mainly the Plantone but added the FF duo very sparingly. It took weeks into flowering for me to start feeling confident of my work with her but finally her colas and the other buds started to fatten up. She looked so impressive but only for a few weeks. She started to yellow about week 4 which I fully expected but then the yellowing spread quickly. Everywhere except the colas and the ancillary buds. And there are many ancillary buds. I resisted the temptation to cut them off and let her focus on just the two main colas. Because while some growers think this is the only way, I'm more of a gentle farmer and see this as mutilation of the plant instead of focusing growth. I may be wrong but that's my style for the present.

So she's now about 8-9 weeks into her flowering, give or take 1 week. You can see that the buds look to be top quality but I won't know for sure for at least another month after harvest and curing. I gave one of the main colas a gentle squeeze this morning and she's dense and thicker than previous grows I've done. The heat here worries me as one previous grow produced enough high quality weed for at least 3 years for my rate of smoking, only about 2-3 joints per week. But the buds were airy and wispy. Hardly any weight to them at all. A gallon glass jug of them weighed only a few ounces.

Late in her flowering I started to sprinkle a pinch of FF Open Sesame on the soil before I watered her. Later I used FF Cha Ching. And when I say pinch I mean no more than 1/2 teaspoon, probably not even 1/4 teaspoon. I've burned plants before and it was always traced back to when I started adding FF Open Sesame and FF Cha Ching. So I went easy on them. She continued to yellow, but the buds got bigger and fatter with each passing day. I would marvel on the day after I watered her how her buds would swell and get frostier.

As you can see from the photos, she's yellow but the bud sites are still green and plentiful. The problem is all those burned leaf tips. Or maybe it's not a problem. The buds look fine but those burned leaf tips tell me I did something wrong ... again. And this is my confusion. I've burned or at least what I'm told is nute burned every grow I've ever done. It's definitely hot here and that I can't control as I grow outdoors in pots. So is this a case of too much or not enough nutes that caused the dark leaf tips. Could it have been just the heat. She did well, in spite of almost constant +90° F days and the nights were only a few degrees cooler.

I have started to flush the pot. This morning I add 3 gallons of water and like before very little run off was noted. The pot she's in is huge. And when I lift it to move her especially after watering this thing must weigh 70-80 lbs. It's like lifting a bag of Sacrete at the DIY stores. I would like to give her 2-3 more weeks, only one more problem has cropped up. Some teenagers in the neighborhood know about her. I don't trust them at all and I'm sure some of them have their eyes on her. I hope I'm wrong but in addition to all the nute issues I have the thieving teenagers to deal with too. Surprisingly and like my previous grow several years back, this one has been pest free. No spider mites, white flies or mold to deal with. No eggs under the leaves, I check for this regularly. But darn it, this is why it's so confusing. Several people tell me too many nutes, several others say not enough. Add to that there is a risk of bugs and some distrusted teenagers. It's enough to drive a grower crazy. Oh, did I mention that it's still illegal where I live and you gotta know that at least one police helicopter has observed her from on high. "I'm so confused!"

 

[Bush Doctor 77]

Looks pretty good to me. Got some fading, but it's that time of year.

 

[Emilya Green]

You are misdiagnosing the tip "burn" as it appears to be the opposite of what you are assuming it is. Along with the overall yellow color as well as your description of barely giving her any nutrition at all in your personal interpretation as to how to use the Fox Farm nutrients, I am more convinced than ever that you are starving your plant of the nutrients it needs.

Not every tip necrosis denotes a burn. Typically a burn is just the very tip of the leaf... a very little triangle, sometimes almost too small to notice. Anything larger than that is usually showing you a deficiency. Your leaves are showing a deficiency of Nitrogen with their pale color and that elongated tip necrosis is classic potassium deficiency.

Of course your buds are still looking fine, because that is what these plants do... they sacrifice everything, even their very own lives, to complete those buds. A plant that is getting proper nutrition does not have any trouble doing this, and does not need to fade. Fading might be common, because the soil around a plant in the wild can be depleted of nutrients throughout a grow, and because indoor gardeners oftentimes believe in the myth that it is best to starve the plants at the end, but it is not necessary or even desirable to allow your plant to fade. A plant fed properly to the end does not fade, and it still produces righteous buds.

Flushing is the opposite of what is needed here. You will no doubt see worse yellowing and more dying as a result of the extended water only. Pull out the Fox Farm feeding guide, and acquaint yourself with Beasty Bloomz... the soluble you should be using right now, and give this poor baby a proper feeding of the full nutrient suit at the rate suggested by Fox Farm for this week of the grow. Stop applying the granules to the soil and stop being afraid of the nutrients you have purchased. Your big girl needs some nutrition, and you need to learn to read your plant a little better, taking the clues the leaves are giving you along with your knowledge of what you are giving the plants (or not giving) to make your diagnosis.

 

[Bush Doctor 77]

You are misdiagnosing the tip "burn" as it appears to be the opposite of what you are assuming it is. Along with the overall yellow color as well as your description of barely giving her any nutrition at all in your personal interpretation as to how to use the Fox Farm nutrients, I am more convinced than ever that you are starving your plant of the nutrients it needs.

Not every tip necrosis denotes a burn. Typically a burn is just the very tip of the leaf... a very little triangle, sometimes almost too small to notice. Anything larger than that is usually showing you a deficiency. Your leaves are showing a deficiency of Nitrogen with their pale color and that elongated tip necrosis is classic potassium deficiency.

Of course your buds are still looking fine, because that is what these plants do... they sacrifice everything, even their very own lives, to complete those buds. A plant that is getting proper nutrition does not have any trouble doing this, and does not need to fade. Fading might be common, because the soil around a plant in the wild can be depleted of nutrients throughout a grow, and because indoor gardeners oftentimes believe in the myth that it is best to starve the plants at the end, but it is not necessary or even desirable to allow your plant to fade. A plant fed properly to the end does not fade, and it still produces righteous buds.

Flushing is the opposite of what is needed here. You will no doubt see worse yellowing and more dying as a result of the extended water only. Pull out the Fox Farm feeding guide, and acquaint yourself with Beasty Bloomz... the soluble you should be using right now, and give this poor baby a proper feeding of the full nutrient suit at the rate suggested by Fox Farm for this week of the grow. Stop applying the granules to the soil and stop being afraid of the nutrients you have purchased. Your big girl needs some nutrition, and you need to learn to read your plant a little better, taking the clues the leaves are giving you along with your knowledge of what you are giving the plants (or not giving) to make your diagnosis.

I've always looked at fading in late bloom as a good thing. It shows reduced N levels, and oxidation products of N can be health risks. This is also why I flush. Reduced N is the soil also means reduced N in the end product. High N can also inhibit burning, can't it? Am I way off base?

 

[Emilya Green]

I've always looked at fading in late bloom as a good thing. It shows reduced N levels, and oxidation products of N can be health risks. This is also why I flush. Reduced N is the soil also means reduced N in the end product. High N can also inhibit burning, can't it? Am I way off base?

You are... this is an old wive's tale... or should I say, an old grower's tale. While it is true that our plants dont need a lot of N in the late stages of growth, they do still need some. The three macronutrients, NP &K are needed all through the grow in varying amounts. Starving the plant only reduces the eventual size that plant could have achieved with proper nutrition at the end, when the plant needs more nutrition than at any other stage of the grow, to finish out the complete genetic profile of those buds. Keep in mind that the buds can double in size and weight in the last two weeks... and this doesn't happen just by giving the plant air and water.

The real myth is that you can somehow leave some of these nutrients, and specifically the N, in the end product. We now have mass spectrograph technology and we can see exactly what is in our buds when we harvest... guess what... no raw nutrients. It is a myth. The only way to get rid of those tastes that we don't like and the things that make our product burn uncleanly, is to dry and cure properly. A flush at the very end is pointless... while you can flush the salts and leftover nutes out of soil, you can not flush a plant. It would be the same as throwing you in a swimming pool to flush something bad out of your intestines... it is a silly concept.

 

[Bush Doctor 77]

You are... this is an old wive's tale... or should I say, an old grower's tale. While it is true that our plants dont need a lot of N in the late stages of growth, they do still need some. The three macronutrients, NP &K are needed all through the grow in varying amounts. Starving the plant only reduces the eventual size that plant could have achieved with proper nutrition at the end, when the plant needs more nutrition than at any other stage of the grow, to finish out the complete genetic profile of those buds. Keep in mind that the buds can double in size and weight in the last two weeks... and this doesn't happen just by giving the plant air and water.

The real myth is that you can somehow leave some of these nutrients, and specifically the N, in the end product. We now have mass spectrograph technology and we can see exactly what is in our buds when we harvest... guess what... no raw nutrients. It is a myth. The only way to get rid of those tastes that we don't like and the things that make our product burn uncleanly, is to dry and cure properly. A flush at the very end is pointless... while you can flush the salts and leftover nutes out of soil, you can not flush a plant. It would be the same as throwing you in a swimming pool to flush something bad out of your intestines... it is a silly concept.

Are you saying that N content of plants isn't higher when a lot of N is available? I don't flush the plant, I flush the soil for 3 or 4 days to remove available N. BTW, I am an "old grower".

 

[Emilya Green]

but by flushing the soil, are you not attempting to eventually flush the plant? I am saying that the plant takes up what it needs at the end, and it doesn't take a lot of N. But here is the rub... the N in its raw form makes it as far as the xylem, that hollow area in the trunk. From there that nutrient is processed and turned into sugars and complex carbohydrates that actually feed the plant and that can move between the cell walls, and only a small amount of nutrient in a basic form gets stored in specific places in the fan and sugar leaves for future use. If you smoke a lot of fan leaves, you can indeed taste the raw nutrients, but I don't personally smoke that stuff. The buds themselves don't see the raw nutrient.. they see the resins and sugars and all the other things the plant is producing with the nutrients and carbon and water that the plant is processing.

 

[OlderStoner]

Such interesting reading. Love it, love it. My next grow will be awhile so I'll keep all this info in mind. I examined one of the photos closely and wow, some of those ancillary buds are covered in trichomes. Looks like it will be frosty buds for Halloween.

 

[Bush Doctor 77]

but by flushing the soil, are you not attempting to eventually flush the plant? I am saying that the plant takes up what it needs at the end, and it doesn't take a lot of N. But here is the rub... the N in its raw form makes it as far as the xylem, that hollow area in the trunk. From there that nutrient is processed and turned into sugars and complex carbohydrates that actually feed the plant and that can move between the cell walls, and only a small amount of nutrient in a basic form gets stored in specific places in the fan and sugar leaves for future use. If you smoke a lot of fan leaves, you can indeed taste the raw nutrients, but I don't personally smoke that stuff. The buds themselves don't see the raw nutrient.. they see the resins and sugars and all the other things the plant is producing with the nutrients and carbon and water that the plant is processing.

Thanks for taking the time to respond. When you say "raw" do you mean elemental N? Are you saying there is an absence of N bearing compounds in the buds, even if there is an excess in the soil, and there is no direct relationship between available N in the soil and total N in the flower? I had been using GH nutes for decades, and always followed their directions, which included flushing with a mild ionic solution. I thought flushing N from the soil at the end forced the plant to consume N in the plant tissue, thus lowering N in the final product. I must admit that now that I am using MC, I do not flush per what I've been reading here. Even if the N is tied up in compounds, doesn't oxidation destroy the compounds, and release oxides of N? My main concern is minimizing N oxides.

 

[Emilya Green]

I think the main mistake is thinking that there is N in all of the plant tissue. When you take a vitamin, lets say zinc, do you really expect to find traces of zinc in all of your body's cells, or do you expect your body to process that zinc, using it as a building block to turn it into skin and bones and such? The same thing is happening here. Yes, there are places that the plant stores some raw nutrients for future use.... but it is not in the buds. You should not worry about the MC leaving N behind... that is the beauty of MC... it loads all of those nutrients in a near perfect mix for these plants into the xylem along with the water, and the plant then processes what it needs and stores what it can. Nothing is wasted or left behind. If you come in with plain water the next time, a Megacrop plant will begin to starve... there is no residual inside the plant other than what it has stored away, so an MC grower is advised to give the nutrient on every watering.
If you are still concerned, do a proper 3x flush around the 6 week point to clear any possible residuals out of your soil, and then continue feeding, and feed immediately after flushing the soil too so the plant does not starve. When you harvest, be sure to get a good slow dry so that you can cure for at least 2 weeks at 65-59% RH, and all of the bad tastes will leave your product.

 

[The Celt]

Morning guys, let me see if I can convey what Em is telling you in a way that s easer to understand.

@Bush Doctor 77 , you were asking about N levels in your bud, so think of it this way:

When your fan leaves fade like that, and the plant is not root bound and there has been no damage to cause the fade, it’s due mostly to a lack of nitrogen uptake at the roots. Your plant then cannibalizes the chlorophyll in the leaves to provide the N needed for bud growth. Unless your buds are turning yellow, then you have not removed any N from the part of the plant you are using.

Less N in flower is a Bro Science misinterpretation of the fact that plants in bloom use “more” P & K, not “less” N. If you follow the research, past and present, it will tell you to maintain N levels throughout the grow and increase P & K in bloom.

Hope this helps

 

[The Celt]

@Emilya seeing how you are handy, and we are discussing fed plants as opposed to LOS. I have a number of plants in coco, outside, being fed Mega Crop. Does any microbial life colonize coco?

In LOS, I know there are benefits to giving molasses in late bloom for the sugars, amino acids and Vitamin B, but is there any life In coco to break it down and make it usable to the plant?

 

[Emilya Green]

@Emilya seeing how you are handy, and we are discussing fed plants as opposed to LOS. I have a number of plants in coco, outside, being fed Mega Crop. Does any microbial life colonize coco?

In LOS, I know there are benefits to giving molasses in late bloom for the sugars, amino acids and Vitamin B, but is there any life In coco to break it down and make it usable to the plant?

I would think that since there is nothing in the coco for most of the major microbes to feed on, they would not choose to live there and therefore there would be no way to break down the molasses. May I suggest however to use Sweet Candy for that exact purpose... the same goodness and more, in a usable form.

 

[The Celt]

Thanks Em, that was my suspicion I won’t bother with the sweet candy, by the time I got it, it would be too late for most of these girls and using MC was just something to see how it compared to LOS. It’s doubtful I would bother with MC again outside, too much time involved feeding these girls that under normal circumstances (non-COVID) I wouldn’t be able to do

 

[Bush Doctor 77]

Simply put, the N is in green tissue only?

 

[The Celt]

For the most part yes, you can see it, but N is also a major component of DNA and rNA, neither of which you can control and aminoacids.

 

[Emilya Green]

Thanks Em, that was my suspicion I won’t bother with the sweet candy, by the time I got it, it would be too late for most of these girls and using MC was just something to see how it compared to LOS. It’s doubtful I would bother with MC again outside, too much time involved feeding these girls that under normal circumstances (non-COVID) I wouldn’t be able to do

It is good to have another tool in the kit if ever a need comes up.

 

[OlderStoner]

May I trouble you grow gurus for just a little more info. I've targeted the next full moon to harvest so I'm only days away now. The buds have swollen up and are gargantuan with loads of trichomes, most of them are getting cloudy but there are still enough clear that I will give it to that full moon phase. Something I noticed this evening is that the buds seem to be growing more white pistil hairs. And only on the side that faces the window for the last 36 hours. It's indeed noticeable and I think I read somewhere that this is a common even late in flowering. Can anyone spread some more of all that technical jargon about this stage?