Brown spots on leaves

It says its safe, but you make a good point lol, probably will be the last time for that, what would you do now if you were me?

I appreciate everyone’s help. I cut off all effected leaves and they looked better yesterday. What else should i do now? Also i’m going to tk pic of my small seedlings in just a bit and would like if u could point me in right direction with them

Hope it all works out for you. :slight_smile:

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Here’s how 3 of my plants are now. What do you think, and do you have any suggestions?

Overall, they look good. The 3rd pik shows some leaf damage, but it is hard to say whether that was caused by all the rain. Monitor that the next few days. The leaves will not get better, but the new growth and rest of the plant should start to thrive if there are no other issues.

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I moved 15 posts to a new topic: Team, think this could be nutes burn as well but like to get your thoughts

The yellow leaves

Yellow leaves with brown in there too are back. What do I need to do? I have noticed that 2 i planted in ground close to these are doing better. 1 more question. I had 2 plants in 5 gal containers that turned out male. I’ve moved them, but was wondering how far away they should be?

Say…check under the leaf s and see if you see any bugs…ok

B Safe

Ok i’ll check today. I haven’t noticed any, but havent looked real close. Will let u know

Ok. Good deal I just want to rule something out

B Safe

I looked real close and didn’t see anything

More yellow today. Not sure if maybe too compacted in buckets? Don’t wanna loose them

Have. you checked your PH
I believe its
A cannabis phosphorus deficiency generally appears on leaves from the lower/older parts of the plant. The lower leaves turn dark green and start getting spots or big splotches that look brown, bronze or even a little blue. The leaves may thicken and curl, and the affected leaves feel stiff. Sometimes the stems of the plant turn bright red or purple.
A cannabis phosphorus deficiency usually appears with some or all of the following symptoms:

usually affects the lower and older leaves of the plant
leaves darken (turning a dark green, blue or grayish color) and may appear shiny
leaves get bronze, purple or brown spots and splotches
leaves thicken and may feel dry or stiff
stems may turn bright red or purple
Phosphorus deficiencies in the vegetative stage usually appear at the bottom of the plant on some of the oldest leaves, and will progressively climb up the plant if left unchecked.
Cannabis plants tend to love phosphorus in the flowering/budding stage and it is unlikely for a cannabis plant to get too much phosphorus using standard nutrients formulated for a flowering plant like cannabis. Nearly all flowering nutrients will come with an abundance of phosphorus for your plants. So if you’re seeing a cannabis phosphorus deficiency while using standard cannabis nutrients, chances are you actually have a root pH problem (explained below in the solution section)!
Phosphorus (P) is used by your cannabis plant in all phases of growth. It is one of the 3 major nutrients (N-P-K) listed on the front of most nutrient bottles, and phosphorus will be represented by the second number that appears.

When there is a phosphorus deficiency, the lower (oldest) leaves turn dark green, occasionally with a bluish or bronze tinge, and may thicken or curl downard before exhibiting dark gray, bronze or purplish splotches. Sometimes the stems of the affected leaves will turn bright red or purplish, usually starting from underneath.
Cannabis phosphorus deficiency in vegetative stage - First lower leaves turn dark, then get brown or bronzy spots, leaves curl downwards and will eventually turn yellow.
A common “symptom” of a cannabis phosphorus deficiency is red or purple stems. It’s important to remember that some cannabis strains naturally grow with red or purple stems even when all their nutrient needs are being fulfilled, so red or purple stems is not a symptom to worry about on its own.

Do not mistake natural reddish-purple colored stems for a phosphorous deficiency!

When you notice that stems are turning red or purple starting from underneath, it may be a sign of a phosphorus deficiency only if accompanied by other symptoms. If the only symptom shown by your plant is red or purple stems, and you are not seeing any other signs of splotches or unhealthy leaves, the red or purple stems are likely caused by the genetics of your plant. If that’s the case, you have nothing to worry about.Solution For Cannabis Phosphorus Deficiency

1.) Adjust pH to Correct Range

Your cannabis plant may show signs of a phosphorus deficiency if the pH at the roots is not in the right range. That is because when the pH of your root zone is off, your cannabis cannot properly absorb phosphorus through its roots. Therefore the first step is to ensure that you have the correct pH for your growth medium. Learn more about pH and cannabis.

Phosphorus is best absorbed by cannabis in soil at a root pH of 6.2 - 7.0. Phosphorus is best absorbed by cannabis in hydro at a root pH of 5.5 - 6.2. If you believe you have a cannabis phosphorus deficiency, it’s important to check the pH of your root zone to make sure the deficiency isn’t caused by the pH being too high or too low.

If you suspect your growing cannabis plant has a phosphorus deficiency, flush your system with clean, pH’d water that contains a regular dose of cannabis-friendly nutrients that includes phosphorus. This will remove any nutrient salts that may be affected the uptake of phosphorus and help restore pH to the proper levels.

In soil, phosphorus is best absorbed by the roots in the 6.2 - 7.0 pH range (in soil, it’s generally recommended to keep the pH between 6.0 - 7.0, but phosphorus specifically tends to be best absorbed above 6.2 and below 7.0)

In hydro, phosphorus is best absorbed by the roots in the 5.5 - 6.2 pH range (in hydro, it’s generally recommended to keep the pH between 5.5 - 6.5, but phosphorus specifically tends to be best absorbed below 6.2)

2.) Take Good Care of the Roots

Wet, compact soil or overwatering can trigger a phosphorus deficiency to appear even when all other factors are perfect. So make sure you water your plants properly every time to help prevent a phosphorus deficiency.

3.) Provide the Right Temperature

Cooler temperatures lower than 60°F (15°C), as well as large temperature swings, can make it harder for the plant to absorb phosphorus. Cannabis plants are therefore more likely to show signs of a phosphorus deficiency when the temperature drops too low, or if they go through a cold spell.

Cannabis likes a comfortable room temperature (they like about the same temperatures as we do).

Read the cannabis temperature tutorial

4.) Give the Right Nutrients

Most growers have actually already given plenty of phophorus to their cannabis plants since it is found abundantly in quality soil and cannabis-friendly nutrients. However, even if you are giving phosphorus, it’s important to give your cannabis the right ratio of nutrients.

An excess of Fe and Zn may cause the symptoms of a phosphorus deficiency by preventing the plant from being able to absorb phosphorus properly. If you believe there may be a buildup of nutrient salts in your growing medium (or if you are growing in hydro and have not recently flushed or changed your reservoir) you should make sure it’s not an excess of other nutrients that is actually causing the phosphorus deficiency to appear. Flush your plant thoroughly with properly pH’ed water containing a regular dose of cannabis nutrients including phosphorus, or completely change your reservoir if you believe that an excess of nutrient salts may be causing the phosphorus deficiency.

Sources of phosphorus:

Bat guano (phosphorus is readily available, especially if made into a teat)
Bone or blood meal (takes quite a bit of time to break down in soil unless made into a tea first)
Worm castings or worm tea
Soft Rock Phosphate
Fish meal
Most cannabis-friendly “bloom” or “flowering” nutrients contain high levels of phosphorus to aid in flower production, and phosphorus from a liquid nutrient is one of the most readily available forms of phosphorus you can provide to your cannabis plants
If you’ve tried everything else, then you may try adding a higher percentage of phosphorus to your feeding schedule and see if that helps clear up the problem for your plant. Cannabis plants love phosphorus, and therefore it is unlikely that you will give your cannabis too much phosphorus.

Most nutrient systems that are formulated for a plant like cannabis will carry and abundance of phosphorus, especially in budding/flowering formulas, so it is unlikely that you will see signs of a phosphorus deficiency before other nutrient problems when using nutrient systems formulated for cannabis (as long as you keep your root pH in the correct range and prevent the plants from getting cold or being overwatered). If you’ve got very high powered lights, or if your plants are growing in direct sunlight, they may be going through a lot more phosphorus in the flowering stage than average and may need you to provide extra phosphorus to make sure buds get as big as they could be.

Just remember that if there’s no actual phosphorus deficiency currently appearing on your cannabis plant, adding more phosphorus is probbaly not going to help plants grow better or make bigger buds - in fact adding too much phosphorus may actually hurt your plants by preventing the uptake of other nutrients! While it’s difficult to overdose your plants on phosphorus, adding too much compared to other nutrients will often cause other strange & unexpected deficiencies to appear.

5.) Take Good Care of the Roots

Phosphorus deficiencies can show up with the plant is having root problems or if the plant is overwatered, even if the pH is right and the phosphorus is there. Proper watering practices help plants grow healthy and avoid a host of problems!

6.) Watch for Recovery

After going through all the above steps, watch to make sure that the phosphorus deficiency starts to clear up within a few days to a week or so. After a phosphorus deficiency is cleared up, the problem (brown spots, unhealthy lower leaves, red/purple stems, etc) will stop appearing on new leaves, usually within a week.

Please note that leaves which have been damaged by a phosphorus deficiency will probably never recover or turn green, so you want to pay attention to other leaves for signs of recovery.

You can cut paste this or save it for future reference

B Safe

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Tha ks thats great info. Yellow leaves are preety evenly spread out and feel wilted and soft

I dropped in to answer the "how far away to move males form females. There is no distance great enough. The wind will carry pollen all over the place for miles. If you want to keep males, and I cannot understand why…You have to quarantine them. Good Luck :slight_smile:

I thought briefly about keeping them if I could move them far enough, but decided it wasn’t worth the risk. They have since gone bye bye lol. Thanks for all your doing to help me out.

I really need some help again . Please take a look at the pictures I posted here and tell me what I should do . Everything was going good and for some reason I decided to flush with pH 7 water and this happened the next morning.

I would have to think, or guess the digital pH tester is the more accurate, and if that is the case, the other tester is about useless.

A pH of 3.5 in soil is way way too low. You really want it about 6.5 in soil.

And go ahead and remove all the dead leaves, they’ll only trap moisture and give a place for pathogens or pest to take hold.


Thanks for getting back so quick. I figured a pH of 3.5 wasn’t good at all. What do you recommend to quickly but safely raise the pH up ?

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This is great stuff. You can get it Amazon or I think any place that sales pool or garden supplies.