Hi! I’m in the 4th week of flowering phase of my plant , I’m cultiving indoor with my lamp 250 w hps a lot leaves have become yellow , I tested the light it’s not too near the leaves, I’m not giving too much water and considering how the full leaf is yellow I guess it’s not a problem of magnesium. In your opinion what could be the problem? I’m giving biobiz fish mix/ bio bloom/ top max. I took these photos with the light on , I hope you can help anyway
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Yellow leaves during mid flowering phase
- Thread starter Gio88
- Start date
The white spots look like thrip damage or something. Have you checked the leaves for insects?
do you think in few days leaves can become so yellow? Thanks
Leaves can go pale for few different reasons
- Lack of nutrients/too mild nutrient solution.
- Under watering ..the leaves don’t even have to droop much but if slight under watering goes on for too long, esp. under hid lights, it can lead to leaves going pale.
- Also over watering, but then the leaves would droop more than on those photos.
- Dry and cold air can have a dramatic yellowing effect on some strains. I had a X18 paki plant that went almost white-ish yellow with out the leaves drying out or dropping off when i grew it during N European winter season. Never seen that on any other plant that much, thou UK Cheese genetics do not like cold dry air either.
Personally i would be more concerned about the white spots/tracks on the leaves first ..and after that about the yellowing. I’d find a magnifying glass asap and go thru the whole plants for signs of insects.
Few photos in more natural light than the orange-ish hps light would be helpful to see better what's going on. Maybe few close up photos of the white spots also, over and under sides of the leaf.
- Lack of nutrients/too mild nutrient solution.
- Under watering ..the leaves don’t even have to droop much but if slight under watering goes on for too long, esp. under hid lights, it can lead to leaves going pale.
- Also over watering, but then the leaves would droop more than on those photos.
- Dry and cold air can have a dramatic yellowing effect on some strains. I had a X18 paki plant that went almost white-ish yellow with out the leaves drying out or dropping off when i grew it during N European winter season. Never seen that on any other plant that much, thou UK Cheese genetics do not like cold dry air either.
Personally i would be more concerned about the white spots/tracks on the leaves first ..and after that about the yellowing. I’d find a magnifying glass asap and go thru the whole plants for signs of insects.
Few photos in more natural light than the orange-ish hps light would be helpful to see better what's going on. Maybe few close up photos of the white spots also, over and under sides of the leaf.
Yeah I second what GoatCheese is saying about the lights in the pics the yellow coloring that comes from an HPS bulb just makes it very hard to tell what is what. I also agree that whatever is causing that spotted effect is most critical, I've been fairly lucky and never had to deal with insects much so I can't say what it is but it just seems too randomly distributed to think it's caused by some sort of nutrient issue. Another thing that can mimic lots of different problems is if you have a ph issue which can cause nutrients to be locked out, which ones depending on if the ph is too high or too low. You say you're sure your not giving too much water which tends to rule out leaching which can also cause yellowing. So I'm inclined to think it's some ph issue (maybe just a little off) combined with some sort of pest problem but if you can post a pic or two in normal light it would help us to make a more conclusive evaluation.
The next time you water your plant's water until you get a little run-off out of the bottom of the container. Then use your EC meter and get a reading from the run-off. If it is low you need to add fertilizer, if it's high just use water.
Those leaves look very odd and unhealthy.
The yellowing and the white spots really don’t look like watering or nutrient feed related. I think it’s been caused by insects and looks alot like thrip damage.
If you get a confirmation that it’s thrips, then you have to keep spraying your plants for some weeks atleast three, till you’re sure they’re gone.
Spinosad, natural pyrethrins and neem oil etc. are what you need to get rid of those fuckers, if that’s them.
Because you’re already blooming your plants spraying those will ruin the smokes but maybe you could use the sprayed bud for edibles as long as you’re using organic insecticides . Thrips don’t like misting with water either but all the spraying obviously isn’t ideal when buds are forming cause it can lead to bud rot.
If it’s thrips, i would take a growing break after this grow and really bug bomb and clean your grow space till you’re sure you don’t have them in your home anymore. IF you have normal house plants it’s likely those plants might have trips also, but you can use systemic and synthetic pesticides on those.
Thrips will develop a tolerance to insecticides like Spinosad and pyrthrins and this is why you have to change the stuff you’re using after a week or so.
Neem oil will mess with their hormonal system which will then affect their ability to develop a tolerance to bug sprays and reportedly will also mess their hormones involved in reproduction/ mating habits.
When i was battling thrips, and i’m still paranoid if i really managed to kill all of them i used Spinosad for 2-3 sprays (a week+) and then changed to pyrethrins and then back to Spinosad AND every other spray was always with Neem oil + soap. So; Spinosad-neem-spinosad-neem-spinosad-neem-pyrethrin-neem-pyrethrin-neem-pyrethrin-neem-spinosad-neem ..and so on.
Thrips are apparently clever fuckers and cuold run and hide when you disturb the plant so tke your time looking thru the plant with a magnifying glass. If it’s not thrips, i’m quite sure it’s some other kind of pest doing the damage, cause it’s not over or under watering nor too mild nutrient feed.
If you don’t have a good magnifying glass at hand you can take a white piece of A4 paper, shake the plant over it and see if any insects drop on it.
Here’s a thread about getting rid of thrips:
..you can find lots of information about thrips around the internet and how to fight them.
Thrips 101: Introduction to Western Flower Thrips
https://www.icmag.com/forum/marijuan...-flower-thrips
When we talk about better picture quality we're mainly referring to the pictures being taken under the HPS light, this gives off a yellow tint to everything and that makes it difficult to evaluate any discoloration in the leaves because it's hard to separate what is caused by the problem from what is from the coloring of the light. If you want to give people good pictures to judge by go in the grow space with just an ordinary light, turn of the grow light and take pictures in the ordinary light. You only need a few good pics so you should be able to get it done in less then a minute. Then you can turn your grow light back on and remove the ordinary light. Having the grow light out for less then a minute will not affect your plants.
I'm still leaning towards it being a combination of a pest problem and a ph problem. It's hard to tell for sure because of the tint from the HPS lights but the affected leaves look like they have some yellowing with a translucent quality to them which can be a sign of a potassium issue. You've mentioned something else though that has me wondering. Again the lighting makes it hard to tell for sure but what I'm saying is a translucent look might also be a mold/fungus issue and you said in these latest pictures the leaves are drier. Does that mean you've been misting the leaves and if so when are you doing that? Really misting should be restricted to just the vegging stage as there's less risk of mold developing but if one mists it's best to do it when the grow light is off. Water droplets on leaves under a high intensity light, like an HPS, can act like magnifying glasses do under the sun. They can focus that light enough to leave burn marks which could explain what I'm saying looks like signs of pests. I still think it's pests though because when I've seen leaf burn from misting under a high intensity light it looks different then that but again the tinting from the HPS might be making it look different. Also if you mist you should do so with just clean water. Leaves can take in some nutrients but they're really not meant to yet people often try to turbo charge growth by spraying nutrients onto leave as well as feeding the roots with them. Those nutrients sprayed on can leave deposits on the leaves after the water evaporates which can also look like odd markings, although again it usually looks different then what I'm saying looks like signs of pests. Now if you spray a plant down when the light is out but in flower the 12 hours of dark gives an extended period for that moisture to just sit there and cause mold or mildew. So again it's best not to mist plants in flower.
So I'm still think a combination of a ph problem with a pest problem or a mold mildew problem with a pest problem and possibly a ph problem with a pest problem and a mold mildew problem. I'm going to attach a sick plant chart that will list various signs of issues and what typically causes them in the hopes it will help you to recognize something maybe I'm not seeing. A warning on the ph problem, ph issues often mimic nutrient deficiencies or toxicities and has often been misdiagnosed causing people to add more nutrients or give less nutrients and if it's the wrong diagnosis that can lead to the problems getting worse. That's why I tend to rule out ph first because then you can be more confident in diagnosing a deficiency or a toxicity.
All them spots are where insects are sucking the life out of your plants. That alone may be your problem, but it would be interesting to hear how much bloom they are getting, and what substrate it is. It's about now that many pseudo organic grows will exhaust the substrate. It's pretty much clockwork for many. So we could do with knowing your container size to.
Find the bugs. Sometimes it's worth taking leaves if they are covered in bugs, just to get the bugs out. The leaves are still useful to the plant though. Providing energy they will have to find from somewhere else, if you take them off.
Find the bugs, as they appear to be the problem.
Dry=how you bought it.
Does your bio bloom say X amount every second watering?
Find the bugs, as they appear to be the problem.
Dry=how you bought it.
Does your bio bloom say X amount every second watering?
Those white spots/stripes got to be caused by insects and look alot like thrip damage.
Like i suggested before, if you can’t see any bugs – thrips move quite fast and can run for cover once you disturb the leaf they’re on - take few white pieces of paper and shake the plants on top of them and see if something drops on the paper.
Also look for tiny dark/black spots on the leaves. Those are spots of shit thrips leave behind.
Like i suggested before, if you can’t see any bugs – thrips move quite fast and can run for cover once you disturb the leaf they’re on - take few white pieces of paper and shake the plants on top of them and see if something drops on the paper.
Also look for tiny dark/black spots on the leaves. Those are spots of shit thrips leave behind.
You didn't say how much you are feeding, only how often. So I'm asking if you are following the bottles directions. I doubt you are..
There does look like there is a feed problem, not just bugs alone. So I'm wondering if you read the bottles. I have to start somewhere.
You ”doubt” he/she isn’t giving enough nutrients even thou the amount of nutes hasn’t been mentioned?! Very scientific approach.
If you look at the photos you can see the leaves that aren’t as damaged looking green enough and you can also see the color of the water leaves being quite green. The plants are getting enough nutrients, the problem is with the bugs. NPK nutrient deficiencies do not create such blotchy yellowing, thirps do. Get a clue. Internet is full of photos of thrip infested plants.
Maybe you should learn how to read plants abit better when you have been show photos and assume/doubt abit less.
