i decided i would stop procrastinating and get to adding a new section to this thread... i decided to go with a all about nutes section.. pretty much everything i can tell you about nutes. deficiencies, burn, lock out, fixing, ect..
we all know, or should know, the nutrients act as food for plants... your plant uses 3 main nutes, known as macro nutes (n-p-k), 3 secondary nutes, and a bunch of other micronutrients throughout it's life... so are used mainly during specific growth cycles, while some are used throughout... having a good knowledge of them will help you know when to use more/less of what, and can also help you figure out problems you could be having...
the npk values show a percentage of the weight that the total nutrient has of that specific nute.. so 6-2-3 would be 6% N, 2% P, and 3% K in the package... organic nutes tend to have a lower npk than chemical.. but thats not always true... and dont let the numbers fool you.. they are plenty strong even with low numbers... liquid nutes also tend to have lower values because they are already diluted in some amount of water.. they are super concentrated tho, so again be careful...
each nute is used at different rates, so they will need to be replenished in different amounts.. this is difficult to do with an all purpose food... if your plant doesnt use as much phosphorus as it doesnt nitrogen, you could end up with phosphorus build up in your soil, which could lead to burn.. this is another reason the 2 and 3 part systems are better.. they are easier to control specific nutes during specific times... you can still use a 1 part system just fine, just make sure to be easy on it....
now before i get into the nutes and their functions i want to talk about nute burn, deficiencies, and how to start fixing them..
burn comes from over feeding your plants.. deficiencies are from a lack of specific nutes.. and lock out is when a nute becomes unavailable due to the soil PH... PH plays a huge part in nute absorbtion and useage.. if the PH of your water or soil is too high or too low you will run into lock out... this is actually the largest cause of nute burn or deficiencies... for instance your soil ph is low, which locks out some nutes, so the salts in them just remain in your soil... you start to see signs of a deficiency, so you try to over compensate with nutes, further adding more salts to your soil, increasing the lock out as the soil PH continues to drop.. then you have to start worrying about burn too because now the plant is getting more nutes (since you added more to make up the deficiency) and so on and so forth...
so what do you do when you think you are having problems with burn or deficiencies?? well the first place to start is your PH... with soil this means the water you feed with, the run off of your water, and the soil itself... having the ability to check the PH of all 3 of those is priceless... especially soil PH.. if your soil PH gets fucked it can lead to a lot of issues.. so get a water ph test kit and a soil ph test kit... if you are using a hydro system, you should already have a ph meter.. its more important with hydro growing than with soil, due to the fact hydro will affect plants more and faster since there is no buffer between the nutes/water and the plant itself...
now you want a soil ph and water ph of around 6.5 for soil growing and for hydro around 6.0.... this will help to keep all nutrients usable.. in a hydro system its easy to adjust the ph.. a little ph up or ph down will do the trick.. dont use the stuff you use for fish tanks... yes, i really do need to say that... make sure you get some ph up or down that is actually meant for hydroponics.. in soil its a little more tricky... you can use hydrated lime, dolomite lime, hardwoodash, crushed marble, or even crushed oyster shells to raise soil ph... depending on your soil and its composistion it will take different amount of any of them to raise the ph to where you want it.. peat moss is a great way to lower your soils ph.. there are also some soil acidifiers you can purchase that will help to lower the ph.. you will find you will need to raise your soils ph more often than lower (if you need to adjust it at all)... either way, whatever you need to do, do it over a few days time (soil) or a .2 or .3 ph change in hydroponics.. to much of a swing to fast can cause osmotic shock...
if you have checked your PH and its within range, then its time to move on to step 2... if you find it is a deficiency in a specific nute, increasing the amount of nutes you are using is the answer... i dont mean two or three times more.. but a slight increase in strength is needed.. if the nute is a secondary or a micro nute you may need to purchase a supplement with whatever nute you are deficient in it...
if you have over fed your plant and have nute burn you will need to flush your plant... flushing involves running a high amount of water or 1/4 strength nutes through your soil or hydro system.. this removes the salts and salt build up in the medium and plants... and yes, using a 1/4 strength nute application to flush with will actually remove more salts than just plain water.. you should flush soil with about 2 times the amount of water as the size of the pot... so for instance use 10 gallons of water for a 5 gallon pot.. if you are using hydro you can use a flushing agent to help out also...
now i think that pretty much covers everything except the nutes themselves... i will give a little info on the nute itself, how to check for a deficiency or burn, and how to treat accordingly... for this section i will assume that you have already checked your PH and its right...
nitrogen - this is the N in N-P-K.. it is used throughout the veg growth cycle mainly.. it is used in large amount so it must be replenished often... your plant willl use a little in the beginning of flowering as it transfers from veg to flowering.. but after a week or so of flowering it is not needed.. or not needed in high amounts.. a small amount of N throughout the entire grow will help to keep your plants green until the end.. but isnt needed...
nitrogen deficiencies are usually pretty easy to spot... during the veg growth stage you will start to see slow growth, growth may stop, but the sure sign is yellowing.. it will start on older leaves towards the bottom and progress up through the plant.. most of the time you will catch it early, and it will be fixed.. but in severe cases it can cause leaves to fall, as they do late into flowering... to correct a nitrogen def simply feed with some nitrogen based nutes.. for nitrogen toxicity, flush medium...
phosphorus - the is the P in n-p-k... it is used during flowering mainly, although some is used throughout the entire growth.. if you try to flower without having enough P available to your plants, you will end up with a very small or no harvest at all... its also used in many other ways by the plant.. its part of the plants DNA, it allows for the transfer of energy within the plant, is associated with seed production and overall plant vigor..
P deficiencies can be a little harder to spot... leaves may show blueish green spots.. stems, leaf stems, and main veins may redden or purple, although the coloring may not always be well pronounced.. sever P def can lead to purple, almost black, nacrosis spots on the leaves... deficiencies are usually caused by soil being below PH 5.8 or above 7.0... or the medium has an excess of iron and zinc which makes the medium chemically bound with phosphates... to fix this problem, just make sure PH is correct... actually this is about the only reason you should have P deficiencies...
toxicity is a little harder to determine... it can actually appear as a deficiency of zinc, iron, calcium, and/or magnesium.. it can also take several weeks to surface... if you find you are having signs of the def i said, and are using a supplement such as CalMag, you may very well have P toxicity and should flush... P build up interfers with the absorbtion of the before mentioned nutes...
potassium - the is the K in n-p-k... this is used throughout the entire growth process as well... it has many functions from assisting in cell division to regulating stomata openings to better use light and air... it also helps strong roots, and is associated with disease resistance and water intake..
K definciencies can be hard to see.. the plant will initially appear healthy.. after a while the leaf will develope spots, turn yellow, and die.. internal leaf temperatures will climb which degrades the cell walls or burns them.. the burning usually occurs at the edges of the leaf.. the stems can often become weak and brittle.. to fix a deficiency you can feed with an all purpose plant food, a nute higher in K value, or water with wood ashes mixed in you water... the wood ash will raise you water PH, so make sure to adjust it prior to actually watering your plants...
when K build up occurs it impairs other nutrient functions too.. this can cause multiple symptoms that will appear as magnesium, manganese, and sometimes iron or zinc def.. again, if you are using a supplement with those nutes, and are still seeing signs related to their deficiencies, you may have a K build up.. flushing your soil and returning to a normal feeding schedule should correct the problem..
now here are the secondary nutrients your plant uses...
magnesium (mg) - at the center of every chlorophyll molecule is an MG molecule.. it essential to the plant for proper light absorbtion.. MG helps with nute utilization, helps enzymes make carbs that are used later to make flowers, and keeps the neutralizes soil acids and toxic compounds produced by the plant..
mg defs are fairly common indoors.. they start as yellow spots between veins on the leaves.. rusty brown spots start appearing, and then start curling upwards as the def progresses.. it starts at the bottom and works its way up the plant.. the brown spots dry and die in extreme cases.. fixing these is a breeze.. water with 1 to 2 teaspoons of epsom salt per gallon of water you are using.. you can foliar feed it to your plants also.. if you do, make it a 2 to 5 percent solution.. use the salts until the signs completely disappear..
mg toxicity is rare in soil... it can affect other nutes in hydro set ups.. but since reservoirs get changed frequently its not a huge problem...
calcium (ca) - fast growing plants will use almost as much CA as they will other macro nutes... make sure you are supplementing CA to your plants.. it helps to keep membranes permeable which helps to keep things flowing with in the plant correctly, keeps cell walls and root walls strong, and is needed at every root tip or growing roots...
ca defs are uncommon and hard to detect... stems might get weak, and new growth may develope yellow to purple hues.. flower growth is inhibited, and plants are stunted.. feeding a supplement to your plant such as CalMag or any similar product with eliminate this problem..
ca build up can cause wilting, and lock out other secondary and micro nutes.. this is rarely a problem as plants can typically use more ca than is available to them... as long as you are supplementing your plant you should not have to worry about ca problems..
sulfur (s) - sulfur has many functions from being the building block for many hormones and vitamins, to being a PH buffer once its turned into its sulfate version..
sulfur deficiencies are similar to nitrogen defs, but backwards.. new leaves will start to yellow first... the veins will remain green, while the leaf continues to yellow and stems purple.. to fix a def either water with a hydroponic nute that contains sulfur, or you can use mushroom compost or animal manure (make sure its well rotted manure so you dont burn your roots)... you could also use inorganic sulfur, but you must mix it with a fertilizer that contains magnesium sulfate..
sulfur build up can block uptake of other nutes.. in a low ec environment sulfur will not be a problem tho.. this is a very rare thing.. but as with any build up a good flush fixes the problem..
and finally the micro nutes/trace elements your plants need..
zinc (zn) - zinc is used mainly as a catalyst for most of the plants enzymes and auxins.. it is crucial of stem growth, sugar, and protein production.. it also works with many other nutes to help assist their functions..
zn defs usually occur in soils with a 7.0 or above ph.. signs start out as interveinal cholorosis.. new leaves become thin and whispy.. leaf tips start to burn, which can spread throughout the leaf.. the signs are very similar to a magnese or iron def, but zn defs end with dried out contorted new leaves... a zn def will stunt all growth.. using a micro supplement or feeding with a zn containing nute will take care of the def.
zn toxicity interfers with iron, and cause an iron def.. zn build up leads to plant death.. again flush well with a 1/4 strength nute app, and start over after that...
manganese (mn) - magnese works mainly in the leaves with nitrogen utlization and the chloroplast membrane system...
def starts with interveinal cholorsis on young leaves, and progresses to older ones.. dead spots will appear on highly affected leaves.. plant growth is stunted and maturation can be prolonged.. to treat the def leach the soil and feed with a micronute supplement... this is common indoors, so using a micro nute supp will help avoid this issue..
mn build up causes new and young growth to form dark orange/rusty brown spots, before it spreads to the older leaves.. low humidity can increase how fast this happens.. raising your ph and humidity can help fix the problem while you flush, but be careful not to raise your ph to much that it locks out other nutes... build up or mn can lead to zinc and iron defs...
iron (fe) - iron is fundemental to many plant functions that are related to sugar energy usage, chlorophyll production, enzyme systems, and even respiration..
iron def are most common when ph is above 6.5, and almost never happens when its below 6.5.. interveinal yellowing starts in the bottom of the leaf, where it meets the stem, and works its way outwards towards the leaf tip.. it starts on smaller leaves and moves to larger ones.. severely affected leaves will eventually fall off.. sometimes iron def can be traced to excess copper if the ph is correct.. lowering your ph below 6.5, and using less manganese, zinc, and copper will help to clear up the issue... after a few days your plant should green up and you can continue feeding normally..
iron build up is very rare.. it can turn your leaves bronze colored and will affect phosphorus uptake... a good flush will take care of this..
here are a list of the other trace element your plant uses, but are rarely ever deficient..
boron
chlorine (in the form of chloride)
cobalt
copper
molybdenum
silicon
nickel
sodium
flouride
there is still an even smaller list of them that some plants need.. but they arent worth mentioning..
the easiest way to avoid deficiencies is to use a good nutrient from a good manufacturer.. its easy to buy the cheap stuff, but it can cause issues later on.. investing in a good nute system will keep your plant healthy and happy...
