I have six plants, they are 2 months old-still in growth not flower mode. they are all planted indoor using Miracle-Gro Cactus, Palm, & Citrus Soil in 5 gal buckets for very good drainage. Run off PH 7-6.4 (mostly lower). Lights- one 400 watt MH and eight T5 HO bulbs (4 white, 2 super blue, 2 purple). rotating fan (24 hrs), 78-81 F. Using Cal-Mag, HydroGuard every watering. MaxSea (16-16-16), FloraNova (7-4-10) rotating basis about every other watering.
Problem: lower leaves turning yellow then brown and fall off. On some plants, leaves curl downward like a claw, some edges of leaves curl.
It looks like you’re dealing with heat issues which could be because of toxic build up because of pH kind of out of whack at the root Zone and it looks like over feeding so you’ve got quite a few things going on there not sure where you should start first other than to try and get your pH dialed in and maybe a really good flush… But stop with the nutrients and just water for a couple weeks… And see what others have to say…
3 Likes
Exactly as @peachfuzz has stated, you need to flush and back off the nutrients. Have you been keeping a journal of how much you’ve been feeding?
Consider doing what peach fuzz said right away and you’ve got to get your pH in Balance, do just exactly what he said for starters, I would do it asap too !
-good luck
Thanks for the quick replies! I thought the temps 78 to 80 F were ok. I thought the ph from 7.0 to 6.0 is a good range for these plants.
Here is a pic from today to give you an overall image of how they look.
1 Like
You keep saying 7.0 - 6.0 and I’m not sure what you mean by that ?
…if you’re putting your nutes in at 6.5, which you should be, it should not be coming out higher than what you’re putting in ?
NITROGEN DEFICIENCY
Here is a pic of nitrogen deficiency
Problems with Nitrogen being locked out by PH troubles.
Waterlogged soil and Soil with low organic matter.
Nitrogen is a very important element in the plant, all of them are but some are more important than others. For soil the best ph to have is 6.8. Why? Because at 6.8, that’s the best number for ALL available nutrients to be absorbed into the plant without any of them being locked out. For hydro and soil less mediums best ph to have is around 5.8.
Try not to keep your plants to cold, because the cold temps will cause the nitrogen harder for the plant to be absorbed.
PH levels for Nitrogen:
Soil levels
Nitrogen gets locked out of soil growing at ph levels of 4.0- 5.5.
Nitrogen is absorbed best in soil at a ph level of 6.0-8.0. ( wouldn’t recommend having a ph of over 7.0 in soil) best range to have nitrogen is a ph of 6-7. Anything out of that range will contribute to a nitrogen def.
Solution to fixing a Nitrogen deficiency
Avoid excessive ammonium nitrogen, which can interfere with other nutrients. Too much N delays flowering. Plants should be allowed to become N-deficient late in flowering for best flavor.
A goof solid N-P-K ratio will fix any nitrogen deficiency. Any chemical or organic fertilizers that have Nitrogen in them will fix a nitrogen deficiency., Peters all purpose plant food 20-20-20 is good, Miracle grow All purpose plant food, Miracle grow Tomato plant food, (Only mixing at ½ strength when using chemical nutrients, or it will cause nutrient burn!) as well and blood meal! If you need to give your plants a quick solution to nitrogen and you want to use blood meal, I suggest making it into a tea for faster use, where blood meal is slow acting, but when made into a tea it works quicker! Other sources of nitrogen are dried blood, Cotton seed meal which is slow acting, Insect eating bat guano which is fast acting. Bone meal which is a gradual absorption when not made into a tea.( also excellent source of phosphorus). Fish Meal Or Fish Emulsion is a good source of nitrogen and is medium acting. Worm castings, which is gradual absorption. Seabird guano, All purpose Millennia Seabird guano, Orginal Seabird guano All Purpose, Crabshell ,which is slow absorption. Fox Farm Grow Big, which is fast acting. ( can bring down your ph as well)
Here are a list of things that help fix a Nitrogen Deficiency:
Chemical Nutrients
Advanced nutrients Grow (2-1-6)
Vita Grow (4-0-0),
BC Grow(1.2-3.2-6.5)
GH Flora Grow (2-1-6)
GH Maxi grow (10-5-14)
GH floraNova grow (7-4-10),
Dyna gro Grow (7-9-5)
Organic Nutrients
Dr. Hornby’s Iguana Juice Grow (3-1-3)
Advanced Nutrients Mother Earth Grow (1.5-.75-1.5)
Earthjuice Grow (2-1-1),
Pure Blend Pro (3-1.5-4)
Bone Meal(0-10-0)
Blood Meal(12-0-0)
Fish Emulsion (5-1-1)
Seabird Guano (11-13-3)
Crab Shells(2.5-3.0-.5)
Pure Blend Grow (0.4-.01-.5)
Marine Cuisine (10-7-7)
MaxiCrop Seaweed (1-0-3)
Super Tea (5-5-1)
Mexican Bat Guano (10-2-0)
Sea Island Jamaican Bat Guano (1-10-0)
Kelp Meal (1-0-2)
Seaweed Plus Iron
Neptune’s Harvest (2-4-0.5)
Alaska Start-Up(2-1-2)
Bio-Grow (1.8-0.1-6.6)
Age old Grow (12-6-6)
AGE Old Kelp (.30-.25-.15)
Neptune’s Harvest (2-4-1)
Maxicrop Seweed(.1-0-1)
METANATURALS Organic grow (3-3-3)
METANATURALS Organic nitrogen (16-0-0)
So adding anyone of these above should fix up your nitrogen deficiency! Nitrogen deficient plants usually recover in about a week, affected leaves will not recover.
Hope this helps
Will. 
1 Like
I mean that the range of the PH (draining water) has varied somewhat between 7 and 6.5 over the 2 months. Currently its 6.5. The roots are not waterlogged-this soil won’t allow it. So does everyone agree it probably is low N. This pic was taken this morning.
I just did a PH test of nutes water going in (6.3) and water draining out the bottom of the bucket (5.3). After I measured plain tap water (7.0) using this meter.
Yes, the journal says rotating nutes added to tap water allowed to breathe for 24 hours every other watering. Just using plain water the other watering days.
If it’s low nitrogen it could be because you’re locking it out with improper pH
Have you checked and adjusted your pH meter?
It’s brand new and I calibrated it using the 3 different powders supplied and distilled water. I left a container under the plant drain and tested that after about an hour. It read 4.6, then tested the plain distilled water, it read 6.8
So is it very low PH or N?
Yes it’s very low, I recall they pre-soak it like Rockwool what I think is going on is your pH is very low from the coco medium because it wasn’t pretty soaked
I would put through water at 7.0 or maybe a little higher (? But be Careful, maybe use plain distilled ?) to get the ph up where I wanted it that would get my run off up into the high fives hopefully and that’s what you want, get your pH above 5.6 asap
In this case I think flushing with high pH water is your best bet, no nutes, let’s get the pH adjusted and you should see them pick up in a couple days get your pH Up in your run off water by feeding it lots of high ph flush water
Its ph lockout (Mag) and some nitrogen toxicity
Specialty soil for cacti and succulents.
Fast draining formula contains a mixture of sphagnum peat moss, composted forest products, sand and perlite that is excellent for growing cactus, palm, citrus and other succulents
Feed for up to 6 months with Miracle-Gro® Continuous Release Plant Food <----**
Great for Succulents
Slow release fertilizer never goes well with cannabis and will make flushing hard to do and you tend to find its a problem at the stage your at with your plants
1 Like
I’m going to get into to trouble for posting a large post. But we have been barki g up the wrong tree on this one…lol
So here she is :
Phosphorus Deficiency
Phosphorus Deficiency
Problem: A cannabis phosphorus deficiency generally appears on leaves from the lower/older parts of the plant. The lower leaves may turn dark green or yellow, 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, but not always.
This marijuana plant leaves are showing signs of a phosphorus deficiency
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 may start turning yellow if the phosphorus deficiency is left untreated, or if the deficiency is combined with other nutrients deficiencies and/or pH problems.
leaves get bronze, purple or brown spots and splotches
leaves thicken and may feel dry or stiff
stems sometimes turn bright red or purple, but not always
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.
The progression of a cannabis phosphorus deficiency
The progression of a cannabis phosphorus deficiency
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)!
This cannabis leaf is showing the final fatal signs of a phosphorus deficiency
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. Leaves occasionally get 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 - Brown splotches, dark bluish color, curling and affected parts of the leaf turn yellow.
Sometimes you will get a cannabis phosphorus deficiency, and the stems do not appear red or purple at all, or the coloring may not be pronounced.
Cannabis phosphorus deficiency in vegetative stage - First lower leaves turn dark, then get brown or bronze spots, stems may turn red or purple starting from underneath, leaves curl and twist downwards and eventually turn yellow.
The leaf below was at the bottom of the plant and turned dark green and shiny, with a bluish tinge. Cannabis phosphorus deficiencies usually appear on the lower/older parts of the plant. The leaf then started showing the spots of a phosphorus deficiency where it was being touched by light (the parts of the leaf working hardest). The leaf began to curl downwards and turn yellow.
Notice that the stems or veins never turned red or purple on this leaf, except for some parts that were actually affected by the phosphorus deficiency.
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.
Healthy purple stems on this cannabis plant are caused purely by genetics, not by a phosphorus deficiency
Phosphorus is used heavily by cannabis plants in the flowering phase to produce buds, and is a crucial component of photosynthesis (turning light into energy for the plant).
Some strains of cannabis use much more phosphorus than others, or be more susceptible to a phosphorus deficiency, and you may have many plants in the exact same setup with only some of the plants showing signs of a phosphorus deficiency.
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
Crabshell
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.
Leaf Color:
Edges Appear Brown or Burnt
Pale Color Leaves
Yellow Leaves - New Growth
Yellow Leaves - Lower, older leaves
Dark or Purple Leaves
Black or Gray Patches on Leaves
Red or Pink Color on Leaves
Brown or Dark Spots
Mottling / Mosaic Pattern
Leaf Symptoms:
Upper Leaves / Newer Growth Affected
Lower Leaves / Older Growth Affected
Small Inner Leaves Affected
Leaf Edges Appear Burnt
Leaf Tips Appear Burnt
Leaf Tips Die
Thick Growth Tips
Red Stems
Spots
Mottling / Mosaic
Old Leaves Dropping Off
Slow Growth
Twisted Growth
Abnormal Growth
Leaves Curl Under
Plant Symptoms:
Red or Purple Stems
Weak Stems
Old Leaves Dropping Off
Slow Growth
Twisted Growth
Leaves Curl Under
Too Short
Root Symptoms:
Slow Growing
Other Symptoms:
Buds Not Fattening
Spots on Leaves?:
Will.
1 Like
the nutes you are using are all apparently high in nitrogen… it may be a deficiency but my guess is there is some other underlying reason as your Ph has been in the right range for nitrogen uptake…
@garrigan62 might he have a case of salt buildup causing lockout? maybe he should flush the crap out of it then just go straight water for the next week or so … is there a way to add nitrogen with a foliar spray?
1 Like
I decided this pH pen (new) is a piece of junk. Even in the calibration solution it couldn’t maintain the 4.0 or 6.8 if I removed it and then replace in the same solution. Any suggestions of a reliable one?
I decided to use ClearEx on all the girls and in a couple days, after they dry out I’ll use clear water
I do need a new pH meter, like to keep the cost below $50, suggestions?
Thanks for all your help and I will keep you all informed