Hey everyone! Looking for some help with my plant on my first grow. Currently in flower and have noticed these small brown spots appear. I have 3 plants and only 1 is affected, all fed the same. Feeding them Canna Coco AB with PK13/14 during the previous week. Any advice is greatly appreciated.
Brown spots
- Thread starter kruroisoi
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Hot and dry?
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- #3
KeithLemon
Well-Known Member
Welcome to 420 I cannot read leaves yet, but someone will most likely be around to help, If you happen to need any nutrients or chemicals to fix your issue, please check out our sponsors!
Welcome to 420magazine my friend.Hey everyone! Looking for some help with my plant on my first grow. Currently in flower and have noticed these small brown spots appear. I have 3 plants and only 1 is affected, all fed the same. Feeding them Canna Coco AB with PK13/14 during the previous week. Any advice is greatly appreciated.
Canna a/b are you in coco coir?
Are you using calmag?
In your plain water first.
Following schedule for nutrients?
What’s ppm?
How often you feeding?
And what ph? 5.8
We need a little info Amigo.
Then we can figure it out.
Take care talk soon.
#VIVOSUN #Love What You Grow
Bill284
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- #6
Sorry I wasn't very detailed,
Yes I'm using coco perlite 70/30, I have not used a calmag at all as when I was researching people were saying there should be enough in my tap water plus in the coco AB but that could be wrong. I haven't been following the dosage as its very high, I've been feeding around 1.5EC. The first 4ish weeks my pH was unknown as I was using a meter that was out by 1 whole pH! But for the past few weeks I've been using a new meter and feeding around 6pH
Yes I'm using coco perlite 70/30, I have not used a calmag at all as when I was researching people were saying there should be enough in my tap water plus in the coco AB but that could be wrong. I haven't been following the dosage as its very high, I've been feeding around 1.5EC. The first 4ish weeks my pH was unknown as I was using a meter that was out by 1 whole pH! But for the past few weeks I've been using a new meter and feeding around 6pH
Here is what I do.
I add calmag to my water first no matter what.
Coco drains it.
Then add nutrients according to recommendation from manufacturers.
Then last set ph to 5.8 exactly.
Then feed every day until runoff.
Keep coco wet all the time.
Never any plain water.
This will help your girls.
#VIVOSUN#Love What You Grow
Bill284
- Thread starter
- #8
Copied and pasted from a seed vendor:
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The following represent symptoms of a calcium deficiency:
New growth at the top of the plant is primarily affected.
Young growth slows, new leaves curl. Fresh growth is twisted and dies off quickly. Young shoots are purple or yellow.
The root system is compromised so fewer nutrients will be absorbed. Overall growth slows and plants lose their lustre.
Flower growth severely affected, especially at peak florescence. Young calyces are crinkled, distorted and don't fill out.
Large, light brown necrotic spots form on leaves. Leaf edges mottle and turn brown. Leaves become yellow as the problem advances.
Branches are weak and break easily. Stalks may become hollow and rot inside.
Plants do not respond well to heat.
Roots become brown and are susceptible to slimy root rot and other pathogens.
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Calcium is an immobile nutrient. New growth as mentioned in the paste will show signs of deficiency. As also mentioned they are more susceptible to heat. I see a few "tacoed" leaves in the first photo, making me think Cal could be an issue.
Mag is displayed as intervenal chlorosis. Though most packaged nutes are paired as "Cal-Mag".
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The following represent symptoms of a calcium deficiency:
New growth at the top of the plant is primarily affected.
Young growth slows, new leaves curl. Fresh growth is twisted and dies off quickly. Young shoots are purple or yellow.
The root system is compromised so fewer nutrients will be absorbed. Overall growth slows and plants lose their lustre.
Flower growth severely affected, especially at peak florescence. Young calyces are crinkled, distorted and don't fill out.
Large, light brown necrotic spots form on leaves. Leaf edges mottle and turn brown. Leaves become yellow as the problem advances.
Branches are weak and break easily. Stalks may become hollow and rot inside.
Plants do not respond well to heat.
Roots become brown and are susceptible to slimy root rot and other pathogens.
-
Calcium is an immobile nutrient. New growth as mentioned in the paste will show signs of deficiency. As also mentioned they are more susceptible to heat. I see a few "tacoed" leaves in the first photo, making me think Cal could be an issue.
Mag is displayed as intervenal chlorosis. Though most packaged nutes are paired as "Cal-Mag".
- Thread starter
- #10
Thanks for your reply, that's a good observation as I have 3 plants and only 1 affected. The affected plant with brown spots is the only one tacoing too.
cbdhemp808
Well-Known Member
Bill has spoken! I will just add... the brown spots look like Ca deficiency. The tacoing can be a heat issue. Are you measuring 22°C (72°F) under the lights? Possibly tacoing can be caused by light intensity, causing light avoidance. How far are your lights from the top of the plants? Can we see a photo of the whole grow?
- Thread starter
- #12
I have picked up some calmag and added to their recent feeding and have also turned down the left light to half strength to help her recover. I am measuring the temp by the small device hanging on the left next to the sick plant. The lights would be about 8 inches from the top of the taller colas but ive ran out of room to move them higher.All 3 are the same autoflower strain and the middle and right plant are perfectly healthy apart from the right plant being smaller since day 1.
In coco the widest range of nutrients available is at 5.8
As long as your pretty close you should be fine.
Try and stay there if you can.
#VIVOSUN #Love What You Grow
Bill284
- Thread starter
- #14
cbdhemp808
Well-Known Member
This is looking like classic boron deficiency... a mild case.
Check out this page from our sponsor, Royal Queen Seeds:
"Boron deficiencies usually occur when a plant is under-watered or subjected to low humidity. Boron deficiencies can mimic calcium deficiencies as both elements rely on each other to maintain overall plant health."
your plant
boron deficiency
Regarding temperature... seems you are just fine on that. So perhaps the tacoing is because of light avoidance... good thing to turn down the light on that side. The other plants are looking great.
Check out this page from our sponsor, Royal Queen Seeds:
Boron Deficiency In Cannabis Plants - RQS Blog
Although rare, a boron deficiency can severely compromise your marijuana plants. This is how to identify and treat a boron deficiency in cannabis.
www.royalqueenseeds.com
"Boron deficiencies usually occur when a plant is under-watered or subjected to low humidity. Boron deficiencies can mimic calcium deficiencies as both elements rely on each other to maintain overall plant health."
your plant
boron deficiency
Regarding temperature... seems you are just fine on that. So perhaps the tacoing is because of light avoidance... good thing to turn down the light on that side. The other plants are looking great.
- Thread starter
- #16
Much appreciated. Any ideas on why a possible boron deficiency has occurred? I've always been battling high humidity and I have been watering daily up until the last 4 days when I've started to water twice a day as they've been very thirsty
This is looking like classic boron deficiency... a mild case.
Check out this page from our sponsor, Royal Queen Seeds:
Boron Deficiency In Cannabis Plants - RQS Blog
Although rare, a boron deficiency can severely compromise your marijuana plants. This is how to identify and treat a boron deficiency in cannabis.www.royalqueenseeds.com
"Boron deficiencies usually occur when a plant is under-watered or subjected to low humidity. Boron deficiencies can mimic calcium deficiencies as both elements rely on each other to maintain overall plant health."
your plant
boron deficiency
Regarding temperature... seems you are just fine on that. So perhaps the tacoing is because of light avoidance... good thing to turn down the light on that side. The other plants are looking great.
cbdhemp808
Well-Known Member
Funny you should ask, because – for the first time ever – I have noticed this same coloring on one of the top buds on a greenhouse plant that I'm flowering (soil grow). The plant is almost ready to harvest, and she's at the end of her lifecycle. She has been in a 5 gal pot, which is really too small for the size of the plant. I'm guessing whatever boron was in the soil in the beginning has been used up, and not replaced. This could have been fixed by some addition of kelp meal – kelp meal contains boron. A tea or ferment could be made to pull the nutrients out of the kelp into water, and then water the plant with it.
- Thread starter
- #18
Canna coco has 0.007% boron but maybe that's not enough, im not sure where I can find kelp meal readily available near me, am I able to use borax?Funny you should ask, because – for the first time ever – I have noticed this same coloring on one of the top buds on a greenhouse plant that I'm flowering (soil grow). The plant is almost ready to harvest, and she's at the end of her lifecycle. She has been in a 5 gal pot, which is really too small for the size of the plant. I'm guessing whatever boron was in the soil in the beginning has been used up, and not replaced. This could have been fixed by some addition of kelp meal – kelp meal contains boron. A tea or ferment could be made to pull the nutrients out of the kelp into water, and then water the plant with it.
Kelp Meal has to break down. Liquid Kelp would be quicker. I used to be able to find it at Lowe's in the states. I now have to find ours on Amazon.
If sticking with a natural or organic source there are plenty of options.
There is a Coot's recipe for making a concentrated Kelp tea out of the Kelp Meal. This can be stored in the fridge. When needed the grower can add a tablespoon or so to a gallon of water and use it as a foliage spray or double the amount and pour it on the soil. If I am remembering right it will be on the Build-a-Soil website somewhere.
Over here, the Liquid Kelp type of products are still in the big box home improvement stores, regular gardening stores and grow shops. Often have a low number, like 0-0-1 or 0-0-2 on the NPK rates.
An alternative is a dry form of Kelp extract. Put a tablespoon or whatever the label says in a gallon of water. Shake it up and instant Liquid Kelp. These have a pretty high number on the NPK rating; something like 0-0-29. Down-To-Earth and several other companies have this type of Kelp extract.
I don't know if there is Boron in the stuff and this is not Kelp but there is Langbeinite. Langbeinite contains 22% Sulfur, 22% Potash and 11% Magnesium, without the salt molecules of Epsom Salts. It is mineral which can give rating close to 0-0-22 when looking at the NPK numbers. The stuff I get has a pinkish color. I have put two tablespoons in a gallon of water, shook it up every now and then and it is dissolved in 48 to 60 hours. Or a table spoon or two and it can be top-dressed on top of the soil every month or two. Check the box for how often to top dress. And, there are products containing pulverized Langbeinite. Kind of like mixing up instant Potassium and the K in the NPK rating can get as high as 50.
