Whats going on here? Outdoor

All plants have now them.
We have rain season and high humidity.
Or some nutes dont came by?
Or tobacco virus?

I would check for pests. I know it’s kinda not related, but aphids did similar damage to my Apple trees.

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With all the rain, probably a fungus among us. Stand by, researching for a fix for you!

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@garrigan62 @MattyBear @Myfriendis410 does this look like the beginning of mildew maybe?

Calcium Deficiency

by Nebula Haze & Sirius Fourside

Cannabis calcium deficiency - leaf closeup

Problem: Calcium is an important nutrient which helps provide structure to the cannabis plant and helps it withstand stress like from heat.

A cannabis calcium deficiency can sometimes be difficult to diagnose since calcium deficiencies are often accompanied by magnesium, iron, and/or other cannabis deficiencies.

Learn more about the relationship between calcium and other cannabis nutrient deficiencies

Calcium moves relatively slowly through the plant (it is a semi-mobile nutrient), which means it tends to “stay put” after it’s been given to a leaf. It tends to show up on leaves that are actively growing and getting some amount of light.

Calcium deficiencies most often show up in the following places:
Newer growth (upper leaves)
Parts of fan leaves that have been exposed to the light

Found near the top of the plant under the light

Picture of a calcium deficiency on a cannabis leaf - white background so you can clearly see the brown spots - calcium deficiencies appear on the upper leaves (new growth)

This lower fan leaf is mostly in the shade, but the calcium defciency appears near the edges that are getting light. Calcium deficiencies often show up on parts of the leaf that are still actively growing.

A calcium deficiency can appear on new growth as well as the actively growing part of a cannabis leaf like this lower fan leaf

Calcium Deficiencies Appear on New or Actively Growing Leaves

Calcium deficiencies tend to appear on newer or growing leaves, which means calcium deficiencies first appear on leaves where there’s rapid vegetative growth.

Some of the most noticeable signs of a calcium deficiency will appear on newer or growing leaves which may display:
Dead spots
Spotting / Mottling
Small brown spots
Stunted growth
Small or distorted new leaves
Curled tips
Leaf die-off
Affected leaves may appear dark green besides the spots

Here’s a close-up of a calcium deficiency that appeared on leaves towards the top of a cannabis plant grown in coco coir:

Marijuana Calcium Deficiency - Closeup of brown spots which first appear on young (upper) leaves

Other Symptoms of Calcium Cannabis Deficiency

If a cannabis plant is affected by a calcium deficiency for too long, it may begin to show the following symptoms due to the lack of calcium.
Stems become weak or flimsy and may crack easily
Stems become hollow or show inner signs of decay
Plant does not stand up well to heat
Flowers/buds do not develop fully, or development is slow
Roots appear weak or under-developed
In severe calcium deficiencies, parts of roots may even die off or turn brown
Roots are more susceptible to root problems like slimy root rot

Cannabis tends to like high levels of calcium, so it is unusual to feed too much calcium when using normal amounts of nutrients and/or regular soil. There are not many known cases of cannabis calcium toxicity (too much calcium), however too much calcium can cause the plant to lock out other nutrients, so it’s important not to go overboard…

Calcium deficiencies are more likely to appear when…
Grower is using filtered or reverse osmisis (RO) water to feed plants – the amount of calcium found in tap water varies, but some tap water has enough calcium to prevent calcium deficiencies
Growing cannabis in hydroponics with nutrients that don’t supplement calcium or when growing in water that has less than 6.2 pH
Growing cannabis in coco coir that hasn’t been supplemented with calcium or below 6.2 pH
When growing in soil or soilless growing medium that hasn’t been supplemented with calcium (usually from dolomite lime) or is acidic (below 6.2 pH)
Too much potassium can also sometimes cause the appearance of a calcium deficiency
Outdoors – calcium deficiency is more likely to appear in acidic soil (below 6.2 pH)

Cannabis Calcium Deficiency - Brown spots on young (upper) leaves

Different strains of cannabis tend to have different nutrient problems. Some cannabis strains (or even specific plants) tend to use much higher levels of calcium than others, and so you may see calcium deficiency problems with one plant even when all the other plants (which are getting the same nutrients and environment) aren’t showing any signs of deficiency.

Solution For Calcium Deficiency in Cannabis

Your cannabis plant may show signs of a calcium deficiency if the pH at the roots is too high or too low. That is because when the pH of your root zone is off, your cannabis cannot properly absorb calcium 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.

Please note: After a calcium deficiency is cleared up, the problem (brown spots and unhealthy new leaves) will stop appearing on new growth, usually within a week. Please note that leaves which have been damaged by a calcium deficiency will probably not recover or turn green, so you want to pay attention to new growth for signs of recovery.
In soil, calcium 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 calcium specifically tends to be best absorbed above 6.2)

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

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

To supplement with extra Calcium… (it’s very rare to give a cannabis plant too much calcium, however, too much calcium can lock out other nutrients so don’t go overboard)

Calcium, magnesium, and iron deficiencies often appear together in cannabis. Many growers decide to purchase some sort of Calcium-Magnesium (often called Cal-Mag) supplement for their grow room in case this common deficiency appears.

Listed below are common cannabis Calcium supplements, along below with some general information about each one. After supplementing with Cal Mag and correcting the pH, you should expect to see new healthy growth within a week. Remember, the old leaves will probably not recover, but new growth should be green and healthy.

Cal-Mag is Well Suited For Hydro, Coco Coir, or Soil

Botanicare Cal-Mag Plus is a calcium, magnesium, and iron plant nutrient supplement. General application is to mix 1 tsp (5ml) of Cal-Mag into each gallon of water. I have used Cal-Mag Plus several times with great results.

Guaranteed Analysis: Nitrogen (N) 2.0%, Calcium (Ca) 3.2%, Magnesium (Mg) 1.2%, Iron (Fe) 0.1%

Derived from: Calcium Nitrate, Magnesium Nitrate, Iron EDTA

Dolomite Lime – For Soil Growers (Organic)

If you’re looking for a way to supplement calcium in your organic or soil setup, I highly recommend a product called “Dolomite Lime.”

Dolomite is a good source of calcium and magnesium and can be mixed with your soil. The great thing about dolomite is it works slowly over the course of a few months.

Dolomite has a neutral pH of about 7.0 and will help keep soil at the correct neutral pH range which is optimum for cannabis growth.

You can buy Dolomite Lime online, but with shipping it’s almost always waaaay cheaper to pick up a bag at a home improvement or gardening store such as Lowes, Home Depot, gardening centers, etc. If possible, try to get a finer grade of dolomite compared to something that is more coarse.

How to Use Dolomite Lime for Cannabis: When growing cannabis indoors, add 6-7 teaspoons of fine dolomite lime to each gallon’s worth of soil. So if you’re mixing enough soil to fill a 5 gallon container, you want to add 30-35 teaspoons (about 2/3 cup) of dolomite lime to the mix. Mix the dolomite lime and the dry soil thoroughly, then lightly water it with water that has been pH’ed to 6.5. After getting the soil wet, mix the soil well and wait a day or two to let the soil settle before checking the pH and adding plants. When growing in an outdoor garden, follow the dolomite lime manufacturers instructions.

Leaf Color
Brown or Dark Spots
Mottling / Mosaic Pattern

Leaf Symptoms
Abnormal Growth
Leaf Edges Appear Burnt
Leaf Tips Appear Burnt
Leaf Tips Die
Mottling / Mosaic
Slow Growth
Twisted Growth
Upper Leaves / Newer Growth Affected
Yellowing Between Veins

Other Symptoms
Buds Not Fattening

Plant Symptoms
Slow Growth
Twisted Growth
Weak Stems

Root Symptoms
Slow Growing


I try to buy some dolomite lime. Its says its Hard to go overboard with this. I t
Sprinkle when all soil are white and then wait some rain to come in again. Bc i think its wet enough to hand water again. I put mi index finger into soil and feel moist. If i drill some holes into soil is this help to aerate roots? Or just gate to water run freely into it?
I know 3 feets deeper where plants are, there are just clay.

just pour it on to the soil, You can loosen up the soil around the plant before watering to

Yeah thats what i plan to do. Scrape some soil loose and feed them. 65days old and some nice buds on them.


Ok, but when you do be very vey carefull not to damage any roots ok


Sure . I know below is same import than up.

I got some dolomite flour and sprinkle on ground like package says and then shuffle dirt and then i poured some nute water there. We will see. Allmost all leaves are affected. I cant pluck them all off…

I add calcium. Nothing.
Now its moving in greenhouse too. And this soil is not lack of calcium.

Can aphids/spider mites/whiteflies/grasshoppers/fungus gnats or any kind of pest do that kind of damage.
I have many crickets and grasshoppers there.
This can be most really that alternaria, I have decomposed pig shit in that growing bed, bed is like hole not like it must be over ground. There can be any pathogens. I try to search this alternarnia in here but nothing.

oh christ, that looks like the hell-fungus that took out 10 of my plants last year :scream::scream::tired_face:

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I have hundreds of crickets, mole crickets, aphids/ants, fungus gnats, whiteflies, spider mites any of them can cause this sh1t. Good airflow and they can’t reproduce.
This fungus “Alternaria” , is going further but I gain my plant good airflow and this is not going further. These are pests, but I don’t know which ones.