N deficiency?
- Thread starter osowhom
- Start date
The Dankstar
Well-Known Member
I'd bring ph down a bit 6.5 range. FF soil runs hot. Follow their chart reduced some. Bottom pic looks like they might be getting pumped a little hard. Easy point to with that soil.
osowhom
Well-Known Member
the pics arent the best but the plant for the most part is light green if that means anything i thought dark green was N toxic
xtsho
Well-Known Member
Kind of hard to tell from those pics but it's not a nitrogen deficiency. I'd say potassium deficiency which is a mobile nutrient and symptoms could start from the bottom. You don't really need to be using calmag with that soil. They use oyster shell as a pH buffering agent and it has plenty of calcium. It also has crab and shrimp meal which are both high in calcium. The Tiger Bloom you're using has an adequate amount of magnesium in it.
I know everyone thinks you need to use calmag but you don't if you're growing in a soil like FFOW that already has enough calcium in it. Too much calcium and magnesium can cause problems with potassium uptake.
This isn't cannabis specific but the principles still apply regarding how calcium and magnesium can affect the uptake of potassium in plants.
"Prophylactic applications of calcium applied as lime or gypsum that are not based on soil test results could create deficiencies in other positively charged nutrients (cations), primarily magnesium and potassium. These cations compete for limited binding sites (very limited in our sandy soils) on soil particles and for uptake by plants. An example below (Figure 1) demonstrates preferential uptake and availability for a paired soil and plant analysis. The soil analysis indicated high potassium and magnesium in the soil but the tissue test resulted in low potassium and magnesium in the plant. Plant analysis for calcium was sufficient. In this case the tomato plants were in good shape with no underlying conditions such as nematode infestation or soil-borne pathogens to inhibit root function. The preferential uptake is where calcium is taken up by the plant and not potassium or magnesium. Deficiencies of both potassium and magnesium can have significant consequences for plant growth and development."
"The effects of calcium and magnesium on the uptake of potassium were generally insignificant in these tests; however, there were some significant reductions in plant potassium uptake as the calcium and magnesium contents of the soil increased. The effect of increased soil magnesium on reducing plant potassium was especially more noticeable than the effect of increased soil calcium."
You always want to maintain a balance in the soil. Constantly feeding it one or 2 different elements that build up in the soil disrupts the equilibrium. I'm not a soil scientist I just read the results of scientific studies conducted by them and base my conclusions off of science.
I know everyone thinks you need to use calmag but you don't if you're growing in a soil like FFOW that already has enough calcium in it. Too much calcium and magnesium can cause problems with potassium uptake.
This isn't cannabis specific but the principles still apply regarding how calcium and magnesium can affect the uptake of potassium in plants.
"Prophylactic applications of calcium applied as lime or gypsum that are not based on soil test results could create deficiencies in other positively charged nutrients (cations), primarily magnesium and potassium. These cations compete for limited binding sites (very limited in our sandy soils) on soil particles and for uptake by plants. An example below (Figure 1) demonstrates preferential uptake and availability for a paired soil and plant analysis. The soil analysis indicated high potassium and magnesium in the soil but the tissue test resulted in low potassium and magnesium in the plant. Plant analysis for calcium was sufficient. In this case the tomato plants were in good shape with no underlying conditions such as nematode infestation or soil-borne pathogens to inhibit root function. The preferential uptake is where calcium is taken up by the plant and not potassium or magnesium. Deficiencies of both potassium and magnesium can have significant consequences for plant growth and development."
"The effects of calcium and magnesium on the uptake of potassium were generally insignificant in these tests; however, there were some significant reductions in plant potassium uptake as the calcium and magnesium contents of the soil increased. The effect of increased soil magnesium on reducing plant potassium was especially more noticeable than the effect of increased soil calcium."
You always want to maintain a balance in the soil. Constantly feeding it one or 2 different elements that build up in the soil disrupts the equilibrium. I'm not a soil scientist I just read the results of scientific studies conducted by them and base my conclusions off of science.
The Dankstar
Well-Known Member
Wow I may try skipping the calmag next time I do some FFOF. A lot of people talk bad about it but Ive actually had great results. You have to take it easy for a while. I've used calmag inbetween feedings with excellent results. Huge results. Just keep ph at 6.5 and if you can get the second bottle that comes with it. Lots of good stuff in there I think its worth it personally. I've went into flowering at 40% the recommended dose until week like 4 (was accident im stupid) and buds and plants were awesome looking. Good luck!
osowhom
Well-Known Member
my first time using cal mag because everyone says cal mag lol ok i will back off
xtsho
Well-Known Member
I don't know if that's the issue just thought I'd throw it out there as something to think about along with links to actual studies. There are many more that also have similar results. The studies show that excessive calcium can impede the uptake of potassium and other nutrients as does Mulders Chart showing synergistic and antagonistic relationships between the various nutrients.
Calcium is a secondary nutrient and is needed by the plant for healthy growth. But the plant only needs so much and as more is added it will build up in the soil which more than likely already has enough calcium for the plant. In addition to that, if you're using tap water then that's another source of calcium.
You didn't say when you started or how often you feed calmag but I've seen posts where people started out feeding it from basically seedling stage in soil using tap water and I always thought that was a bad idea. I think people might think that they're not feeding their plants any nutrients with calmag but they are.
I've never used calmag in my life in either soil, hydro, or coco. I'm not saying not to use it but it is overused as some people add it to every watering which is completely unnecessary.
That's all I got. I hope you get the issue resolved.
osowhom
Well-Known Member
Thanks