Something odd

[drumin]

I noticed something unusual today on the leaves of the unknown Indica that I've had flowering now for 3 weeks. This morning when I carried my 2 potted outside I noticed a discoloration on a lot of the leaves. I fawn over these 2 so I noticed right away. It looks sorta like if you rubbed the color off of the bumps on the leaves. It's not an insect infestation as far as I can tell and I know what mites look like. Could it be lack of nitrogen? My other girl Indica/Sativa looks fine...

[ndnguy]

Mad Scientist





Posts: 211
Join Date: Mar 2006
Location:
In the lab... Calcium (Ca) -Macro Nutrient and an Immobile element.

Calcium is another important element that helps the plants cell walls, cell division in making the plants stems, stalks, branches stronger, as well as contributing to root growth, mostly the newer root hairs, Calcium also helps enhancing the uptake of K in the the plants roots. Calcium moves really slow within the plant and tends to concentrate in roots and older growth.



When plants exhibit a Calcium deficiency the younger leaves are the first to show it as well as older leaves. The Leaf tips will die back, the tips may curl, and growth of the plant is stunted. The plant can show a weakness in the stems and branches, as well as a under developed root system that can lead to bacteria problems with roots dieing off. Having slow plant transpiration rates can aggravate the uptake of calcium. Make sure your soil isn’t very acidic, for calcium gets harder to be absorbed through acidic soils, Which leads to having a plant that is deficient in Calcium. The leaf tips, edges and new growth will or may turn a yellow/brown color that happen in spots and often surrounded by a sharp brown outlined edge and then the leaf tips die back. If too much calcium is given at an early stage of growth it can stunt the growth of your plants. Having to much of calcium will also flocculate when a concentrated form is combined with potassium. The parts affected by a calcium deficiency are the roots. Stem or petiole, young or old leaves.

Too much Calcium will lead to other micronutrient deficiencies. Calcium fixation is caused by many types of mediums such as: clay soils, unbuffered coco and humus. The lime tends to bond to these soils very easily. The stems of the plant will not be able to hold the plant up and will exhibit a white brown in between the veins of the leaves when having too much calcium. Also having to much potassium and or nitrogen will cause a calcium lockout.



Problems with Calcium being locked out by PH troubles

Very acidic soils with excessive potassium, dry and or wet soil. Lack of calcium in the soil may cause too acidic soil. This may cause to Mg or Iron deficiency or very slow stunted growth


Soil


Calcium gets locked out of soil growing at ph levels of 2.0- 6.4
Calcium is absorbed best in soil at a ph level of 6.5-9.1 (Wouldn’t recommend having a ph of over 7.0 in soil) anything out of the ranges listed will contribute to a
Calcium Deficiency.


Hydro and Soil less Mediums

Calcium gets locked out of Hydro and Soil less Mediums at ph levels of 2.0- 5.3
Calcium is absorbed best in Hydro and Soil less Mediums at ph levels of 5.4-5.8 (Wouldn’t recommend having a ph over 6.5 in hydro and soil less mediums.) Best range for hydro and soil less mediums is 5.0 to 6.0. Anything out of the ranges listed will contribute to a Calcium Deficiency.




Solution to fixing a Calcium deficiency
To fix a calcium deficiency you can treat by foliar feeding with one teaspoon of dolomite lime or Garden lime per quart of water, Or Any Chemical/Organic nutrients that have Calcium in them will fix a Calcium deficiency. (Only mixing at ½ strength when using chemical nutrients or it will cause nutrient burn!)
Or you can take crushed up dolomite lime or garden lime in a gallon of water and water it in the soil. 1 to 2 teaspoons per gallon of water, which will be slow acting. Garden Gypsum, which is medium absorption. Limestone, which is medium absorption, Rock Phosphate and Animal wastes which are both medium/slow absorption. Note: Caution when using gypsum to an already acid soil (pH that is less than 5.5) can have a very bad effect on different types of plants by effecting the absorption of soil aluminum, which is poison to plant roots.


Now if you added to much chemical nutrients and or organics, (which is hard to burn your plants when using organics) you need to flush the soil with plain water. You need to use 2 times as much water as the size of the pot, for example: If you have a 5 gallon pot and need to flush it, you need to use 10 gallons of water to rinse out the soil good enough to get rid of excessive nutrients.




Pictures 1-2 shows calcium deficiencies. First one shows late, 2nd one shows early development.

Click for larger image.

[ndnguy]

Calcium leaves...................

[gorilla]

Doesn't look like nitrogen mate.

Awesome answer Ndn.

[drumin]

Thanks for that ndnguy but I'm not convinced that is the problem. mine don't really look like those in the pictures. Here's 2 pics that are a little clearer (I wish my cam had a manual focus instead of this auto focus crap). overnight a few of the leaves started to curl.

[drumin]

Chatted with CB this morning (thanks bro 2thumbs ) and he suggested that I might be giving this plant more "P" than it likes so I'm gonna give it a good flushing, cut back on feeding (I'm using a 10-50-10) and see if it starts to recover. :gthumb:
If anyone else wants to chime in, please do so!

[jj2ss3o2s]

I got that exact same look to leaves when I was using old nutes. could be nutrient lockout.

[drumin]

:stick: JJ, what did you do to fix it?

[jj2ss3o2s]

I bought new nutrients. I noticed it too late, and my plants suffered a lot of burn for it. I thought about flushing the soil but at 5 weeks flowering I thought that by doing that i would remove too many other nutrients still available so I just cut my nurtients down to near nothing, and gave superthrive at every feeding. It supposedly makes nutrients more availabe to plants.

[drumin]

OK so here is the scoop, I decided to give my soil another check with the PH meter before adding a little PH down when I got the idea to stick the rod into one of the drain holes around the bottom of my 5 gal pot. The PH meter dropped to like 3.5 :wow:
So it looks like the soil in the first 6" is testing at just under 7 but at the bottom of the pot it's just over 3. I told my wife and she said that she had some left-over soil from some other plants that were in those about 2 inches and she just put our own potting soil on top of that.

Should I pull the plants and dump that bottom soil and replace it with the same soil used in the rest of the pot?

http://www.homegrownbud.com/forums/attachment.php?attachmentid=5245&stc=1&d=1154442016

[CB]

think i would run 15-20 gallons of water thru the bucket and wait....

i see some claw action going on as well

:2cents:

[drumin]

Flush the hell out of it even 3 weeks into flower? Wouldn't it just be quicker and easier on the plant to just get rid of that acidic soil? The pots are about 9 inches deep and the soil meter I have gets down to about 6 inches and that reading all the way around the plant is consistantly 6.8-6.9 :shrug:

[jj2ss3o2s]

I think transplanting a plant 3 weeks into flowering would be a lot more stress than flushing the hell out of it. If you do flush it your gonna have to count on your bottle ferts a little more a few weeks down the line as there will be little left in the soil. crappy problem to run into buddy, but its a good lesson to learn.