• Home
  • Forums
  • Medical Cannabis Cultivation
  • General Outdoor Growing
  • Need help diagnosing issue with plant.

Need help diagnosing issue with plant.

  • Thread starter Thread starter 757Botanist
  • Start date Start date Jul 23, 2025
  • Tagged users Tagged users None

Need help diagnosing issue with plant.

757Botanist Jul 23, 2025 46 Replies 3,516 Views
Page 1 of 3 · Replies 1–20 of 47
  • 1
  • 2
  • 3
Next
1 of 3 Next Last
7

757Botanist

Posts
180
Reactions
289
Joined
Aug 29, 2023
Points
63
Jul 23, 2025
#1
Hey fellow farmers. My outdoor grow is going well. 4 plants in rotation but one is showing some funky signs. I water with rainwater and fertilize with TPS 3 in 1 and also with TPS bud hardener since they are in preflower. The leaves are turning yellow with brown spots. I do a gallon of water mixed with 5ml of the 3in1 and 5 ml of the Bud hardener. The other three are fine but this one plant is driving me crazy.
 
Reactions: GNick55
Quote Reply

LoveGrowingIt

Supporter
Posts
4,735
Reactions
8,151
Joined
Jul 19, 2023
Points
263
Jul 23, 2025
#2
I'd like to see a picture of the plant that leaf came from.
 
Reactions: Sunasun, GNick55, RoadKillSkunkHunt and 2 others
Quote Reply
7

757Botanist

Posts
180
Reactions
289
Joined
Aug 29, 2023
Points
63
Jul 23, 2025
#3
LoveGrowingIt said:
I'd like to see a picture of the plant that leaf came from.
Click to expand...
Gotcha. Pic 1 is the plant in question the rest are its sisters doing well.
 
Reactions: GNick55 and RoadKillSkunkHunt
Quote Reply

LoveGrowingIt

Supporter
Posts
4,735
Reactions
8,151
Joined
Jul 19, 2023
Points
263
Jul 23, 2025
#4
The plant looks healthy. I think it's beginning to get ready to flower, so it's getting hungry. It needs vegetation nutrients for the stretch and is starting to need flowering nutrients. Calcium and magnesium would help, too.
 
Reactions: Jmaes Mabley, GNick55, RoadKillSkunkHunt and 1 other person
Quote Reply
7

757Botanist

Posts
180
Reactions
289
Joined
Aug 29, 2023
Points
63
Jul 23, 2025
#5
LoveGrowingIt said:
The plant looks healthy. I think it's beginning to get ready to flower, so it's getting hungry. It needs vegetation nutrients for the stretch and is starting to need flowering nutrients. Calcium and magnesium would help, too.
Click to expand...
Thanks! I was freaking out a bit but I will do a couple more weeks of the 3 in 1 bc that has the NPKs the plants need.
 
Reactions: closettrapper217, GNick55 and RoadKillSkunkHunt
Quote Reply

RoadKillSkunkHunt

Posts
1,284
Reactions
2,417
Joined
Mar 23, 2025
Points
263
Jul 23, 2025
#6
757Botanist said:
Thanks! I was freaking out a bit but I will do a couple more weeks of the 3 in 1 bc that has the NPKs the plants need.
Click to expand...
Is your 3 n 1 a one bottle nutrient program? If so, we might want to look deeper into the TPS nutrient line-up. Your plant is about to go through high amounts of calcium and potassium. @LoveGrowingIt already suggested calmag and I'm going to suggest a potassium sulfate boost. I believe TPS has one called "Signal." You'll need those boosts as you head into flowering.
 
Reactions: GNick55, franklygrown and 757Botanist
Quote Reply
7

757Botanist

Posts
180
Reactions
289
Joined
Aug 29, 2023
Points
63
Jul 23, 2025
#7
RoadKillSkunkHunt said:
Is your 3 n 1 a one bottle nutrient program? If so, we might want to look deeper into the TPS nutrient line-up. Your plant is about to go through high amounts of calcium and potassium. @LoveGrowingIt already suggested calmag and I'm going to suggest a potassium sulfate boost. I believe TPS has one called "Signal." You'll need those boosts as you head into flowering.
Click to expand...
Yes the 3in1 is one bottle but I will go back to the website and look up Signal. I did see that. Luckily their products can be mixed so hopefully that’ll do the trick. I already have some calmag but let me check the expiration on it. Thanks
 
Reactions: GNick55 and RoadKillSkunkHunt
Quote Reply

RoadKillSkunkHunt

Posts
1,284
Reactions
2,417
Joined
Mar 23, 2025
Points
263
Jul 23, 2025
#8
757Botanist said:
Yes the 3in1 is one bottle but I will go back to the website and look up Signal. I did see that. Luckily their products can be mixed so hopefully that’ll do the trick. I already have some calmag but let me check the expiration on it. Thanks
Click to expand...

This graphic should help you see why we're suggesting what we are. Calcium needs go sky high about the second week of flowering. Potassium needs go sky high shortly after that. Now is the time to get both in hand as you head into flowering.

 
Last edited: Jul 23, 2025
Reactions: GNick55 and 757Botanist
Quote Reply
7

757Botanist

Posts
180
Reactions
289
Joined
Aug 29, 2023
Points
63
Jul 23, 2025
#9
RoadKillSkunkHunt said:
This graphic should help you see why we're suggesting what we are. Calcium needs go sky high about the second week of flowering. Potassium needs go sky high shortly after that. Now is the time to get both in hand as you head into flowering.

View attachment 2482251
Click to expand...
Thanks this is perfect!
 
Reactions: RoadKillSkunkHunt
Quote Reply
7

757Botanist

Posts
180
Reactions
289
Joined
Aug 29, 2023
Points
63
Jul 23, 2025
#10
RoadKillSkunkHunt said:
This graphic should help you see why we're suggesting what we are. Calcium needs go sky high about the second week of flowering. Potassium needs go sky high shortly after that. Now is the time to get both in hand as you
Click to expand...
Silly question but since the other plants aren’t showing these signs, should I still give calmag and Potassium for preventative maintenance?
 
Reactions: GNick55 and RoadKillSkunkHunt
Quote Reply

RoadKillSkunkHunt

Posts
1,284
Reactions
2,417
Joined
Mar 23, 2025
Points
263
Jul 23, 2025
#11
757Botanist said:
Silly question but since the other plants aren’t showing these signs, should I still give calmag and Potassium for preventative maintenance?
Click to expand...
I would. I'd call it normal plant support in your case. Your plants don't appear to be having real problems so we're going to simply support its growth by providing it what it will be asking for as you head into flower.
 
Reactions: GNick55 and 757Botanist
Quote Reply
7

757Botanist

Posts
180
Reactions
289
Joined
Aug 29, 2023
Points
63
Jul 23, 2025
#12
RoadKillSkunkHunt said:
I would. I'd call it normal plant support in your case. Your plants don't appear to be having real problems so we're going to simply support its growth by providing it what it will be asking for as you head into flower.
Click to expand...
Awesome, just placed order for the TPS Signal, TPS Silica Gold, and the TPS cal mag. Thanks again for the help!
 
Reactions: GNick55 and RoadKillSkunkHunt
Quote Reply

RoadKillSkunkHunt

Posts
1,284
Reactions
2,417
Joined
Mar 23, 2025
Points
263
Jul 23, 2025
#13
757Botanist said:
Awesome, just placed order for the TPS Signal, TPS Silica Gold, and the TPS cal mag. Thanks again for the help!
Click to expand...
Usually a grower will use silica up until about the second to third week of flowering. It's potassium Silicate usually. The signal is potassium sulfate. If you use both at the same time, you could over-do it. Also, the silica has been known to cause burning issues when used through out flower.

Now don't fret your purchase. That Silica will come in handy during your next run. Start giving them some (by the directions) during veg.
 
Reactions: GNick55 and 757Botanist
Quote Reply

GNick55

Staff
Supporter
Posts
15,468
Reactions
49,574
Joined
Jan 11, 2020
Points
438
Jul 23, 2025
#14
you better research septoria and black spot disease,.
 
Reactions: Sunasun, 757Botanist, Putthataway and 2 others
Quote Reply

RoadKillSkunkHunt

Posts
1,284
Reactions
2,417
Joined
Mar 23, 2025
Points
263
Jul 23, 2025
#15
GNick55 said:
you better research septoria and black spot disease,.
Click to expand...
@GNick55 is there something you see that we don't? I've never personally dealt with either one of those issues so all I know is what I've read which isn't much.
 
Reactions: GNick55
Quote Reply

GNick55

Staff
Supporter
Posts
15,468
Reactions
49,574
Joined
Jan 11, 2020
Points
438
Jul 23, 2025
#16
RoadKillSkunkHunt said:
@GNick55 is there something you see that we don't? I've never personally dealt with either one of those issues so all I know is what I've read which isn't much.
Click to expand...
yep, black spot,.. a fungas appears than leaf yellows and dies,.
close up of pics see spots?
 
Reactions: Sunasun, 7munkee, Hossgrows and 1 other person
Quote Reply

RoadKillSkunkHunt

Posts
1,284
Reactions
2,417
Joined
Mar 23, 2025
Points
263
Jul 23, 2025
#17
GNick55 said:
yep, black spot,.. a fungas appears than leaf yellows and dies,.
close up of pics see spots?View attachment 2482369View attachment 2482370
Click to expand...

How would you treat it? Something like Southern Ag's Garden Friendly Fungicide? I don't have first hand experience with this ... tell us what you can and I'll research the rest.
 
Reactions: GNick55
Quote Reply

GNick55

Staff
Supporter
Posts
15,468
Reactions
49,574
Joined
Jan 11, 2020
Points
438
Jul 23, 2025
#18
RoadKillSkunkHunt said:
How would you treat it? Something like Southern Ag's Garden Friendly Fungicide? I don't have first hand experience with this ... tell us what you can and I'll research the rest.
Click to expand...
never dealt with it,.
but it can turn real bad real quick and that plant looks to be early in the infection,..
 
Reactions: Sunasun, 757Botanist and RoadKillSkunkHunt
Quote Reply

GNick55

Staff
Supporter
Posts
15,468
Reactions
49,574
Joined
Jan 11, 2020
Points
438
Jul 23, 2025
#19
RoadKillSkunkHunt said:
How would you treat it? Something like Southern Ag's Garden Friendly Fungicide? I don't have first hand experience with this ... tell us what you can and I'll research the rest.
Click to expand...
just google cannabis septoria black spot
 
Quote Reply

RoadKillSkunkHunt

Posts
1,284
Reactions
2,417
Joined
Mar 23, 2025
Points
263
Jul 23, 2025
#20
GNick55 said:
never dealt with it,.
but it can turn real bad real quick and that plant looks to be early in the infection,..
Click to expand...
This is what AI says about it. I wouldn't use Neem oil this close to flowering but the rest seem like a solid path

Treatment & Prevention Steps​

  • Remove infected leaves to reduce disease spread.
  • Increase air circulation (use fans, thin foliage) to decrease humidity.
  • Reduce overhead watering to keep leaves dry.
  • Apply an organic fungicide (neem oil, potassium bicarbonate, sulfur-based) safe for cannabis if fungal infection is confirmed27.
  • Inspect for pests under leaves with a magnifying glass to rule out mites or other insects9.
  • Monitor nutrients but prioritize fungal management if distinctive black spots with halos dominate the symptom pattern.
 
Quote Reply
Page 1 of 3 · Replies 1–20 of 47
  • 1
  • 2
  • 3
Next
1 of 3 Next Last

Thread info

Replies 46
Views 3,516
Started Jul 23, 2025
Latest post Aug 13, 2025
Starter 757Botanist
Forum General Outdoor Growing

Latest posts

  • how to Bubble washing and tips 2024
    • Latest: GNick55
    • 20 minutes ago
    Concentrates & Processing
  • P
    Indoor vs Outdoor Trichome development and morphology
    • Latest: peterg
    • 54 minutes ago
    General Indoor Growing
  • Eternal Sun 2026 outdoor garden grow
    • Latest: EternalSun
    • Today at 1:00 AM
    General Outdoor Growing
  • 2026 Outdoor Grows! let's see em!
    • Latest: defective
    • Today at 12:20 AM
    General Outdoor Growing
  • Frebo Can’t Stop Growing living in the Woods
    • Latest: frebo
    • Yesterday at 11:47 PM
    General Outdoor Growing
  • Home
  • Forums
  • Medical Cannabis Cultivation
  • General Outdoor Growing
  • Need help diagnosing issue with plant.
  • Contact us
  • Terms and rules
  • Privacy policy
  • Help
  • Home
Community platform by XenForo® © 2010-2026 XenForo Ltd.
Menu
Log in

Sign up

  • Home
  • News
  • Classifieds
  • Forums
    • What's new Featured content New posts New Articles New articles New products Latest activity
  • Social
  • Strains
  • Live
  • Learn
  • Brands
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?