leaves curling down

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DarkHorse007

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Hi ive been a member for a while now and ive been doing alot of reading on the site and have learned alot and have solved any problems ive had from the site but tonight when i checked my plants i noticed that on one of my plants the leaves are curling down i thought they were drooping but they are still rigid. the older leaves seem to be more affected that the newer leaves growing. a few days ago i trimmed a few leaves that had some chemical burn on them and let the sit out in the sun for a while which i had not done with them for about a month could this be the cause? hope this is enough for you to help me out feel free to ask me any questions thanks!
 
do you think the sun that day may have shocked them? are they curling up like a hand making a fist? if so it can be a sign of too much nitrogen.
 
the leaves are curling under and it even kinda looks like the stems also are pointed down more than usual. heat stress is really the only thing i can think of but i had several plants out that day and it is the only one affected. thanks for the reply just thinking out loud hope i can fix this hate to loose this plant
 
if it is a nitrogen problem is there a way i can fix that? i did notice the other day when i had them out in the natural sunlight the leaves looked darker green
 
Heres a before and after pic. the leaves on top are starting to completly die now they are crispy and brown but it is still mostly the older leaves that are afected the new leaf sets except on the top still looks alright
 
pics are a little small had a hard time getting them to import

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What's with the holes in the soil?

I am sorry, I can't tell a thing from those pictures but I bet someone else will be by with some help. Have they had too much water?
 
I would hazard to say that there is nute burn happening there as the leaves are a little dark and have tip burn. Unfortunately the pics are too small to see the smaller leaves clearly enough to tell. That soil looks pretty dense as well, did you mix in any peat or pearlite/vermiculite to break up the soil a bit? That could be AN issue if not THE issue, due to the roots not being able to breath well enough.
 
Plants that have been raised indoors cannot just be put out into direct sunlight without damaging them. They need to be acclimated slowly as the ultraviolet light from the sun can and will damage plants--even those grown under large HIDs.

You say "chemical burn". What exactly does that mean? We generally do notm cut any leaves. When the plant is through with them, it will drop them. I am with Rosebud in wondering about the holes in the soil and with Hushpuppy on the density of your soil. I am thinking that your plant could be suffering from the soil not having good drainage properties. However, we need to know far more about your grow to keep from guessing. Tell us how old the plant is, where you got the seed, what it is planted in, what you feed it, the environment of your grow space (size, lights, ventilation), whether you check the pH of your water, etc, etc....the more info you can give us, the better.
 
yeah, basically all the environmental factors that you are supplying to the plant . . .
 
ok lol heres the rundown the plant is about two months old, i got the seeds from the single seed centre, its planted in a mix of miracle grow potting soil and natural soil from my garden and the ph is at 7.4. ive never thought of checking the ph of my water since i live in the country and our water comes right from a aquifer but i will just to be safe. my grow space is actually about 20x5 but right now im only using about 2x2 of that since i have only a few plants and it stays between 75 and 80 degrees with 40 to 50 percent humidity. i have four 125 watt CFL lights on them and i am using fox farm liquid fertilizers on them about every other week if they are needing to be watered. by "chemical burn" i actually meant to say nutrient burn. lol the holes i poked in when the plant first started to die because i thought it might of been overwatering at first and i had read on another site about someone doing it to dry their soil out faster but it really didn't work lol
 
It looks like a couple of things happening at once. The top of the plant looks like it is surely UV burn, but the curling and yellowing leaves looks to me like the soil is an issue. Growing in miracle grow soil is tricky because you can't tell how fast the nutes are releasing, plus that soil looks quite dense which makes it hoild water which can cause nute and salt build up around the roots.

I personally would get some good organic soil and pearlite and transplant that one (as gently as possible to hold off root shock) Green mojo bro:)
 
thanks for the reply and the advice it is much appreciated i figured that i had some sort of heat stress but didnt know that soil could be such an issue. i started looking at soil mixes tonight also what would you recommend as the best mix i thought that the fox farm mixes might be a safe bet to go with but i thought i would as the pros first
thanks
 
The foxfarms soil and line up is a good brand to use. I know several folks here use it. Some people add to it a bit with ammendments and run it organically, and some use it just straight and then add chemical nutes later when the nutes in the soil is depleted. There are multiple ways to go with it.

I am growing in both hydro and I am in organic with some of my plants as an experiment. I just got some good organic soil mix from Lowes as I couldn't find the one that Hemp Goddess uses. Then I added "Cow Peat" which is composted manure, Espoma's "Garden Tone", I mixed in some "sweet lime" and then mixed in pearlite. The mix proved to be a good mix for doing it myself but I also found that it didn't feed the plants long enough so I had to start using "compost tea". On the next set that I mix up, I will add some bone meal and some microbe enhancements, as well as molasses. All this is for truely organic type of growing and isn't necessary to just achieve a grow. Some think it is better for the plants and improves the quality of the smoke, which is why I am trying it as an experiment.

My hydro setup is using just coco and pearlite and then I use Advanced Nutrients' Jungle Juice 3part with some Magical. This setup can be done as hydro or as just soilless and work just as well. As I said before some people use different soil mixes and then use a more chemical base of nutes.

Goto Plantlightinghydroponics.com and have a look at their growing stuff, then goto discount hydroponics.com and look at theirs. DH has a very exaustive lineup of nutes and soil mediums. These will give you an idea of some of the stuff available. Then read the stickies here and the grow journals of what others here do. The possibilities are wide. The only soil that I recommend against is the commercial, prenuted, time-released, one soil-fits-all type of stuff as that is too not right for the sensitive pallet of MJ. It is fine for the flower beds and shrubs and yearly flower plants but it is not formulated for MJ. Some people use it with success but most have nothing but grief from it.

Good luck with it, don't be afraid to ask questions, we are glad to give advice and generally jawjack about growing :)
 
DarkHorse007 said:
ok lol heres the rundown the plant is about two months old, i got the seeds from the single seed centre, its planted in a mix of miracle grow potting soil and natural soil from my garden and the ph is at 7.4. ive never thought of checking the ph of my water since i live in the country and our water comes right from a aquifer but i will just to be safe. my grow space is actually about 20x5 but right now im only using about 2x2 of that since i have only a few plants and it stays between 75 and 80 degrees with 40 to 50 percent humidity. i have four 125 watt CFL lights on them and i am using fox farm liquid fertilizers on them about every other week if they are needing to be watered. by "chemical burn" i actually meant to say nutrient burn. lol the holes i poked in when the plant first started to die because i thought it might of been overwatering at first and i had read on another site about someone doing it to dry their soil out faster but it really didn't work lol

You need to test your water. Well water can be very high in dissolved solids (basically unknown nutrients) and this can also affect the pH. Your pH is high. You want to be running around 6.8 or so in soil grows.

When we talk about lighting, we use actual wattage rather than equivalent wattage. You are probably running 32W bulbs that emit around 1800-2000 lumens. The difference between those and the sun is immense. Even if you had been running a 1000W HPS, you would need to acclimate your plants to the sun. And while I understand wanting to take advantage of the sun, taking inside plants outside and inside again is really not a good idea. It is easy to bring pests and pathogens into your grow space that are hard to get rid of.
 
thanks for all the advice it is much appreciated and i will keep all those things into consideration. i think i saw a thread on lumens earlier but what is the ideal lumens i should be around? Hushpuppy thanks for the website links they are great sites.
 
When we talk about lumens, we are talking about the level of energy that is being released by a light source in the form of electromagnetic waves and photons of energy. This energy is the key to all life on Earth(hows that for a statement :hubba:) But its true, the plants use this energy to power the chemical reactions that go on in their leaves, which in turn are used to create all of the complex compounds used in the plant to grow it vegetatively and more during flowering.

MJ is a high energy plant and requires a specific minimum amount of light energy (measured in lumens) in order to thrive. Notice I say thrive not survive. Where a lot of people go wrong with growing MJ is that they think of MJ as a "houseplant". It is anything but a "houseplant". These people give the plants just enough energy to survive but not thrive, which is whats needed to produce the quality yields you see peeps here posting.

That said, we measure lighting needs not by number of plants but by the size of the space the plants are in(square footage of lit space). With that in mind it is completely concievable to have a 1000w HPS light over a single plant and still be underlit. The reason is the Physics behind light energy dispersal. The more area a given amount of light has to cover the less amount of light enerrgy there is contacting any given spot. This loss of light energy is also affected by vertical distance as well. There is actually an algebraic formula for figuring the light dispersal within a cubic space since light energy dimenishes over distance. But don't worry too much over that, as we have a relative standard that takes that into account.

Basically you want good quality "blue/white light" for vegging plants. This is given in spectrum as 5000Kelvin, 6000Kelvin, 6500Kelvin. The higher the Kelvin number the bluer to UV the light spectrum goes. Many of us here have found the 6500K lighting to be about the best spectrum of light for vegging plants and maintaining nice tight growth. The amount of light given off by the source of a CFL, T5 flourescent tube, Metal halide, or High Pressure Sodium light is given typically in the US in Lumens. The amount needed for thriving growth is a minimum of 3000 lumens per square foot of lighted area. Any of these lights will have the ability to give this level of light (although not in the same spectrum which is also important).

Since we all are trying to do this for the least amount of cost, we try to get the most cost-effective setups to match our needs. The CFL is the least efficient of the lights I listed (I don't list LEDs because they are a different animal). The T5 high output floro-tube is about as efficient as the Metal halide(maybe more in some ways). The the most powerful yet is the HPS, and at this time, the 600wHPS is the most efficient as it puts out the most lumens per watt of electricity used.

Many people like to use the CFLs because they are compact(and cheap) and work in smaller spaces where less light is needed. Often people will use multiples of these in the cloning and seedling stages where less than 3000Lpsf is acceptable. But once the plants start growing in earnest, the 3000L minimum is needed, with 4-5000Lpsf being better (the ungarded sun is about 10,000Lpsf on average). Once the plants reach the point that they can be induced into flowering, the light energy needs to be increased to accomodate the loss of 12hrs of light per day as you are taking the plants from 24hrs of light down to half at the flick of a switch. Nature does this very gradually and allows for the plants to acclimate. Because we are wanting to make it happen quicker, we cause a great amount of stress on the plant which makes it think that it has become hidden by some external barrier, and begins to stretch itself out to try to find the light again. By increasing the level of lumens to a minimum of 5000Lpsf (with 6-7500 being better), we can offset the shock of loss of light and minimise the stretching as much as possible while still giving the plant all the energy it needs to build the flowers and chemicals we so enjoy. At the point of flowering, most of us switch over to the HPS lighting as that is the most efficient of the light sources, and it gives an added bonus of having the "spectrum" of light that the plants like to have for building flowers (yellow/amberish 2700-3200Kelvin).

If you look up any of these lights, especially in the hydro/grow stores, they will list the spectrum and level of lumen output for a given light fixture or wattage. For example, the 600w HPS gives off about 90-95,000L per light bulb. So for flowering with under the 600w, you could properly light a sqft space of 16sqft, or a 4'x4' area. that same space used for vegging would only need 50-60,000 lumens of light. A 600w metal halide or a 4'T5 fixture with 10 bulbs would work for vegging in that space.

Sorry for the "Lecture on light", I love the science of it all. I hope this help you understand it a little better. :)
 

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