Yellowing, discolouration and minor spotting

[4d-Rock]

Soil ph isn't as big of a concern as your ppms.. That's because you're in pro mix.. Pro mix recommends 5.2-5.8. If you're feeding mix is 550 ppms, then you have to understand or know that the ppms will lower as the plant feeds. The run off should be about the same or lower than your nutrient mix.. If its higher that tells you that the plant is not feeding on the nutrients you are providing. So adding more would not be the correct answer. Again, the highest ppm I've ever used was 500-550 during the last 2 weeks of flower. I would flush (or water with plain 0 ppm water) until the ppms are in range. I'd shoot for 3-400.. Ppm meters are one of the most underrated and overlooked tools. It is the only tool that tells us if our plants are feeding and how much they are feeding. I can't say that you will see any improvement on the purple plant because it's pretty bad off.. They won't regain any color, but it should slow the spread. Your goal for that plant at this point should be to have a few healthy fan leaves left for late flower and harvest.

Thanks @Proph , I figured the damage is done to them, just trying to control what I can and get them to cross the finish line in the best shape possible. I’ll give them a flush today and aim for that 300-400ppm mark.

Is this because I’m feeding with every water? Or is it because I’m not watching runoffs close enough or lowering input feeds if the runoff ppm is getting too high?

This keeps happening with me and MegaCrop and I’m considering starting to look elsewhere. I’ve been growing with it for years now and still can’t seem to get it right.

 

[Proph]

Thanks @Proph , I figured the damage is done to them, just trying to control what I can and get them to cross the finish line in the best shape possible. I’ll give them a flush today and aim for that 300-400ppm mark.

Is this because I’m feeding with every water? Or is it because I’m not watching runoffs close enough or lowering input feeds if the runoff ppm is getting too high?

This keeps happening with me and MegaCrop and I’m considering starting to look elsewhere. I’ve been growing with it for years now and still can’t seem to get it right.

Yes to both questions, lol.. You do not need to " "feed" your plants every day.. Sometimes you get thirsty right? What if someone force fed you a steak to help with your thirst? Or what if someone force fed you for days in a row? That's what's happening with the plants.. Sometimes plants are thirsty.. Sometimes they are hungry.. That's why you check the ppms every other day or so until you see the plants feeding patterns.. If the ppms are the same or higher a day or two after you feed, then you know that plant is not hungry and isn't feeding much/fast, and that food is available should it become hungry. The most common watering/feeding schedule for cannabis is a cycle of feed, water, water, feed.. And this is done "as needed". For example, I feed on Monday.. Tuesday I may or may not water depending on what the pot shows.. Wednesday I check the ppms of some run off using zero ppm water.. If it's still close to my original mix, I will water the plants with plain water. Do nothing on thursday.. Friday, plain water again.. Then Saturday or Sunday make a feed mix.. Unfortunately there are no set rules or steps. The plant will tell you what it needs. It's our job to know those signs.. We as growers usually get into trouble when we starting following these feed charts that companies provide. It's the plant that dictates when it should be fed and how much... Not the writing on the packages. So yeah, feeding everyday will always lead to issues (unless you're hydro of course).. That promotes nutrient build up and leads to lock out.

Honestly bro, Mega Crop has been onsite for a number of years now.. No rep to answer questions.. Several different versions.. And 2 or more big threads filled with MC issues. I used MC for one run. The 2nd version they released.. Shit went haywire at the start of flower (like it does for most) and I never touched it again. Years later Im still seeing people post about the exact same issues, while using newer versions of it. Im just not convinced that MC is made for cannabis growing. Tomatoes? Cabbage? Probably great for those, lol... If you do continue use MC, my best advice is to use the feed calculator on their website. It gives completely different dosages than the bag does.. Much lower.. Growers here on site like yourself, have been trying to "dial it in" for years now. I've been organic for a while so Im not sure what I would/could actually recommend in its place. The Dutch Pro line is really good, but not sure it's available where you are..

 

[Mañ'O'Green]

IMPO The PH is too low in the root zone and that is the problem. I would feed at 6.4 to bring it up in the pot. Mega Crop's early versions had problems with too much N in flower. I have not used the third single part version so I don't know about it. I am using the Mega Crop 2 part with great success. Peat will hold nutrients longer than coco so alternating feed and water days should work ok. Just be sure that when you do feed that the PPMs are around 500.



Mega Crop 2part and Bio-stimulants only.

 

[4d-Rock]

Thanks @Proph & @Mañ'O'Green
I ended up flushing today with a weak balanced nutrient. Basically 0.1g/gal SK/SC, 1g/gal MC, and 0.2g/gal BE for a total of 275ppm/6.5pH.
It didn’t take too much to get the runoff down in each plant, I’m surprised the Red Poison took the least.
The Red Poison took 3L to get to an end runoff 300.
Right Sweet Nurse took 4L to get an end runoff 325.
Left Sweet Nurse took 5L to get an end runoff 370.
We’ll see how they all react to that. I’ve increased the air circulation and turned the QB down to about 65w (tent total 175w) as well to allow for the recovery.

 

[4d-Rock]

Hey guys, things are still looking iffy on the fan leaves, increased spotting and discolouration, though the buds are coming in and the sugar leaves look reasonably healthy.
The left sweet nurse continues to look the best despite the serrations curled up a bit and some tip burn.

last night I did give 2.5L of plain water (60ppm/6.2ph) to each

Red Poison - runoff 400ppm, soil pH 4.5-5
Right Sweet Nurse - runoff 460ppm, soil pH 4.25-5
Left sweet nurse - runoff 240ppm, 5.6-5.9

The ppms are back down and I should be able to give them all a feed of 400-500 next time, but it seems like the soil really wants to stay on the acidic side. After seeing this I figured I’d try giving some of a leftover weak mix I had of 275ppm.
2L each of 275ppm/6.5pH to the Red Poison and Right Sweet nurse
RP - runoff 230ppm, soil ph 5.5-5.9
RSN - runoff 275ppm, soil pH 5.4-5.8

Checked the soil ph of them today and they have dropped back down to 4.25-5.

Not sure if I should be top dressing with some dolomitic lime or if it’s too late for that since it’s a bit slower acting. Or is it time for a more serious flush?

 

[Deke]

They look like plants in flower to me. Those that want true green pants through flower confuse me. Why? Natural yellowing should occur. I'm in my 3rd mega crop grow. I've learned don't feed until week 3 and don't go over 4.5 grams. This is is FFOF. Are your buds growing well, trichomes doing what they should ? Stop worrying about some yellowing in your fan leaves. This isn't rocket science.

 

[4d-Rock]

They look like plants in flower to me. Those that want true green pants through flower confuse me. Why? Natural yellowing should occur. I'm in my 3rd mega crop grow. I've learned don't feed until week 3 and don't go over 4.5 grams. This is is FFOF. Are your buds growing well, trichomes doing what they should ? Stop worrying about some yellowing in your fan leaves. This isn't rocket science.

I agree to a point that a plant should naturally yellow as it feeds off itself in the final stages of flowering. The issue is that it’s happening far too closely to the transition from veg to flower.

Ive pretty much just been keeping at 500-600 ppm with 3g/gal MC and 1g/gal BE to finish them off even though they havent Faired too well. Will make adjustment for next grow and hope I get closer.

 

[Proph]

They look like plants in flower to me. Those that want true green pants through flower confuse me. Why? Natural yellowing should occur. I'm in my 3rd mega crop grow. I've learned don't feed until week 3 and don't go over 4.5 grams. This is is FFOF. Are your buds growing well, trichomes doing what they should ? Stop worrying about some yellowing in your fan leaves. This isn't rocket science.

He's doing the right thing.. Plants do not "naturally fade" when you're feeding your plants nutrients. That may happen if/when you stop feeding the plant in the last few weeks. Leaves are very important to bud production.. The buds can't reach their full potential and the end product will suffer when the leaves are all yellow and eaten through. He's definitely right to be concerned, and is right to want to resolve it.

 

[Proph]

I agree to a point that a plant should naturally yellow as it feeds off itself in the final stages of flowering. The issue is that it’s happening far too closely to the transition from veg to flower.

Ive pretty much just been keeping at 500-600 ppm with 3g/gal MC and 1g/gal BE to finish them off even though they havent Faired too well. Will make adjustment for next grow and hope I get closer.

View attachment 1259338

Try to keep in mind that every plant is different.. Every grow set up is different.. What works for others may not work the same for you... It's much easier to add more nutrients if needed, than it is to remove nutrients if too much has been added. That's why I tell everyone to start with a very light feed and work up to the max range (500ppms). I've been saying this for years, but now it seems most people are just saying to stay under 500ppms.. So people start/stay at 400-500 ppms. Back when I used nutes, 500ppms would be the max I would use on certain heavy feeding plants, in the last feed or two. It was mostly 300-350 until the plants asked for or showed signs that they wanted more. Some plants are light feeders some are heavy.. Some are sensitive to light/environment.. Some are more resilient. I told myself I wouldn't comment on MC posts in the infirmary any more, but I hate seeing these types of issues. Especially when the issues are as simple as over feeding. That's an easy fix once we let the plant tell us how much to feed them rather than a feed chart (all feed charts are recommendations or baselines, not instructions, because every plant is different). Im sure you will do 100 times better on your next grow. Just think of your young plants as growing infants, and ppms levels as types of food.. 0-100 ppms being normal baby food in a jar.. And 500ppms as being steak, lobster and a cold beer.. Start with baby food and work up to the surf and turf!

 

[4d-Rock]

No worries @Proph, I appreciate you chiming in, though there really isn’t too much to say left on this current grow. Things went sideways on this one and now there’s not much to do but stay the course and finish up the best they can. The pic above was from yesterday which is at Day 64. If they were healthier I could see them being 80-90 day finishers, but I may only give them another week or so before cutting.

I think I mostly have the right idea, I didn’t feed til about day 10, starting at 1g/gal, increasing by 1g/gal per week til 3g. but I went wrong on this one by continuously feeding with no plain water breaks. The ppms built up in the soil, tanking the pH in the process, locking things out further.

Next grow, I’ll do the same in terms of slowly building up the strength of feed. But I’ll throw in a plain water between feeds, watching the runoff to keep an eye on what the plants are using. I think I’ll also cut out sweet Candy entirely, stick with only MC and then add some bud explosion in if things are going well when flowering.