Yellow spots, what deficiency or problem?

What do you think it is causing these yellow spots? Some kind of deficiency? I am in week 3 growing autoflower in soil and did not use nutrients so far as I thought the soil would have enough for the first 3 weeks. I only see the spots on that one leaf so far and maybe a single spot on another one.

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OldMedUser

Well-Known Member
A deficiency would affect all the leaves in the same class so it's likely some environmental factor that caused that. A little too much heat, liquid or just a few spots on a leaf.

I wouldn't worry about it unless you start seeing lots more of it. Yellowing of the older fan leaves is the most likely thing to happen as the plant starts running out of food. Then it will be time to start feeding it.

What type of soil is it and what kind of nutes do you plan to feed with?

:peace:
 
A deficiency would affect all the leaves in the same class so it's likely some environmental factor that caused that. A little too much heat, liquid or just a few spots on a leaf.

I wouldn't worry about it unless you start seeing lots more of it. Yellowing of the older fan leaves is the most likely thing to happen as the plant starts running out of food. Then it will be time to start feeding it.

What type of soil is it and what kind of nutes do you plan to feed with?

:peace:
I am using some regular soil from the supermarket, not many choices for me. This is the one :


As for nutrients, I bought some for palm trees and green plants with an NPK of 9-4-5. I also have some universal ones witb NPK 4-5-6 which also contain 1% Calcium
 

go go kid

Well-Known Member
looks like one of those things that happen to a few leaves as mentioned above, i wouldent worry about them unless they start on other ones
 
I lean to calmag also. Try and see. She is young. I wouldnt flood her with nutes..just basic calmag and phed water i think. A little molasses does wonders also. It is loaded with micronutes and sugars. A leaf here and there is common. As long as does not take over. Just my thoughts.
 
I lean to calmag also. Try and see. She is young. I wouldnt flood her with nutes..just basic calmag and phed water i think. A little molasses does wonders also. It is loaded with micronutes and sugars. A leaf here and there is common. As long as does not take over. Just my thoughts.
BTW those leaves have great color. Nice shape. Looks healthy.
 

OldMedUser

Well-Known Member
I am using some regular soil from the supermarket, not many choices for me. This is the one :


As for nutrients, I bought some for palm trees and green plants with an NPK of 9-4-5. I also have some universal ones witb NPK 4-5-6 which also contain 1% Calcium
No list of ingredients on their site but it sounds similar to the Promix Veg & Herb blend or something like a better Miracle Grow soil. I fed early with the ProMix stuff and it was like it released all the nutes in the soil at once and badly burned the plants. Now I use the ProMix HP that has no nutes and add lots of organics that I supplement lightly with 3- part AN nutes, calmag, Epsom Salts and a few other goodies. Just opened 3 new bottles of the AN Jungle juice that has the original AN 3-part formula and no pH Perfect to it.

If that's a good auto it should start showing the onset of flowering in the next 1 - 3 weeks so I would feed a 1/4 dose of that first nute to start with and she how it takes it. After 4 or 5 weeks of flowering I'd then switch to the 2nd one until the end. The NPK ratios aren't bad for veg and flower but would be nice to know what's all in them as far as micronutrients go

One spotted leaf does not a deficiency make but it wouldn't hurt to add something like calmag. Agricultural gypsum is a good source of Ca and S but breaks down slowly and is best mixed into the soil before planting. Epsom Salts are a quick source of Mg and S and should be used lightly thru a grow but heavier the last few weeks of flower. Both are in high demand then as is K.

If you are using tap water you may have plenty of Ca and other things in it.

:peace:
 
If that's a good auto it should start showing the onset of flowering in the next 1 - 3 weeks so I would feed a 1/4 dose of that first nute to start with and she how it takes it. After 4 or 5 weeks of flowering I'd then switch to the 2nd one until the end. The NPK ratios aren't bad for veg and flower but would be nice to know what's all in them as far as micronutrients go


If you are using tap water you may have plenty of Ca and other things in it.

:peace:
Do you think I should start feeding 1/4 dose of nutes when she start preflower or let's say when she enters week 4?
As for water, I am actually using bottled water with a PH of 6, but I am now thinking that it may be a good idea maybe to mix tap water with the bottled one.
 

OldMedUser

Well-Known Member
Do you think I should start feeding 1/4 dose of nutes when she start preflower or let's say when she enters week 4?
As for water, I am actually using bottled water with a PH of 6, but I am now thinking that it may be a good idea maybe to mix tap water with the bottled one.
You should contact your water supplier for a copy of their water analysis report to see what all is in your water. Should be free to get one by email. My tap water comes from a dugout on my property and is really hard at 400+ ppm and pH 8+ so I only use RO or distilled water with a dash of calmag.

What is the bottled water you use? RO or distilled water has no pH really and is neutral as far as it's effect on the soil. Some bottled water is mineral water and should have the mineral content on the label but that's usually expensive compared to 5gal jugs of RO.

When using hard tap water the minerals in the water build up over time in the pots and can skew the pH so it's not completely true that you don't need to worry about pH when using real soil to grow in. Some tap water can be high in various minerals like sodium, iron, manganese etc that can also cause issues with nutrient imbalances leading to lockouts of other minerals. Best to know what's in it.

For years I ran DWC grows using RO water with AN 3-part nutes and never used calmag or ever noticed any Ca deficiencies so the nutes had enough or I would have had problems. I did run into low Mg tho so used Epsom Salts at low doses to correct that.

I would definitely start feeding once you see flowers start on the plant but not at 4 weeks unless you start seeing some yellowing on the older leaves. Not all autos are the same and some may not show flowers until 7 weeks or so but once they do start flowering they begin a growth spurt and will need extra everything. The autos I grew outside this last summer worked out great and I barely fed them anything other than what was in the ground I prepared for them.

Trimmed the fan leaves earlier that day and chopped them down the day after this pic. Mazarilla by Urban Legends and with the seeds I have left I'll be making more fem seeds this winter and growing more of them next summer. The middle plant is a CBD auto that did not yield well so still looking for a good CBD auto strain to grow up here in northern Alberta. These were cropped Sept 11 so well ahead of the frosty weather tho it was dipping to a few degrees above freezing some nights before chopping.

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What are the names of the nutes you have? I'd like to look them up to see what they have in them.

:peace:
 
I am actually not from North America so don't think it will be that easy to find out the tap water content. I did check the bottled water label and it says it has Ca 176,6 Mg/l, Mg 78,65 Mg/l, K 7,56 Mg/l, Na 33,47 Mg/l, Cl 9,9 Mg/l, SO4 32,82 Mg/l, HCO3 10,37 Mg/l, pH 5,99.
As for the nutes, on the palm one it does not really say anything besides the NPK of 9-4-5. And on the other one it says organic carbon 18%, Ph 7,5%, N 4%, P 4%, K 6%, Ca 1%, Mg 0,08%, Fe 0,02%, Mn 0,01%, Zn 0,01%.

I actually noticed another thing now, these white spots, dots on the main stem at the base. Are these normal?

IMG_20211104_204820.jpg


Wow, really nice plants you had there, wish mine would come out like that :)
 

OldMedUser

Well-Known Member
Between what's in that soil you're using, the water and those nutes you seem pretty well covered so if they have good light you should get a decent crop.

Little bumps and things on the stems are pretty normal but I'd let the soil dry out around the stem as if wet all the time stem rot is a possibility. Are you letting the pot get light before watering again so air can be drawn into the soil as it dries? The roots need oxygen and drying the soil helps draw it in.

I was quite pleased with the plants and don't know why I waited so long to get into growing autos outdoors up here but tried regular plants 16 years ago and they don't start flowering until it's a couple weeks from frosty weather.

:peace:
 
I've been using the finger in soil technique for watering. Basically I've been watering every 4 days or so. Last watering was after 3 days. I thought the soil felt dry, but I don't really know how it should feel. It's my first grow ever, hope I'll be able to do it right.
 

Kassiopeija

Well-Known Member
in veg you can try to let the soild dry out for 1 time up to the point where the leaves start hanging down... then lifting the pot to remember its weight, and go by that.

as for your used soil isnt easy to provide you much helpful info as the msnufacturer isnt transparent about ingredients at all, and there are even same branded versions using a different recipe dependant on where you live.
Some time ago I've written CompoSana to inquire about that but a 0-info response came back.

But attention, this soil may contain long-release mineralic/chemical fertilizer pills (6-8 weeks) with its release being able to present salt stress to the roots. Draining 10-20% a good idea.
A number of independant growreports have shown plants turning yellow from the top down with stunted growth at the beginning of flower. Acidified medium around pH 5, high EC salt buildup was the cause of the problem. Turns out the manufacturer uses much filler substances but lack good compost, manure or dolomite so lacking pH stability, his pills the core of the soil so he can just take various ingredients and save up on composting time.

About your water:
is that carbon-dioxided? pH of 6 at that massive Ca & Mg seems awkward. Also Sulphur being lower than Mg is unusual. Could still work, but pH up may become necessary over time. Or mix with tap, which is usually pH 7.5-8
 

cobshopgrow

Well-Known Member
these white dots want to become some roots, thats normal.
if youre from the country composana is from you should be able to see your local water report on your waterworks website.
your mineral water is for sure not too low in Ca, i bet when you let your water of gas the CO2, you wont have a pH of 6 anymore.
maybe see if you cant use your tap water, later in flower you dont want to haul the bottles only for your plant.

is some good alternative to composana, especially as you can download a technical product pdf for every type they sell.
btw. they even sell some "Growmix" now in home depots.
 
About your water:
is that carbon-dioxided? pH of 6 at that massive Ca & Mg seems awkward. Also Sulphur being lower than Mg is unusual. Could still work, but pH up may become necessary over time. Or mix with tap, which is usually pH 7.5-8
Is carbon dioxided water bubble water? If so, no it is still water, some kind of light water, the only one I found in the store with a ph lower than 7
 
these white dots want to become some roots, thats normal.
if youre from the country composana is from you should be able to see your local water report on your waterworks website.
your mineral water is for sure not too low in Ca, i bet when you let your water of gas the CO2, you wont have a pH of 6 anymore.
maybe see if you cant use your tap water, later in flower you dont want to haul the bottles only for your plant.

is some good alternative to composana, especially as you can download a technical product pdf for every type they sell.
btw. they even sell some "Growmix" now in home depots.
Unfortunately I am not from the country CompoSana is. To be honest, this soil was the best, most expensive they had at my home depot. I guess in the future I should just go online for it.
I have started digging for the tap water contents, hope I'll find something
 
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