underwatering?

[Nikijad4210]

That indeed looks very much like heat stress, Skin.
However, it also looks like the start of Phosphorus or even a Potassium deficiency, too. Except, that wouldn't make sense, as his PH is within range for Phosphorus & Potassium absorption......

Wait a minute, Smoke, you said you're giving them light doses of food....Are you feeding at 1/2 strength, 1/4 strength....? And what is the N-P-K ratio on that food?? If you're feeding them too light a dose a food, they might not be getting enough Phosphorus after all, which could explain the damage.

 

[Guest]

the ratio is 3-1.5-4.
feeding 1/4 strength
and they have been veggin for 2-3 weeks now, so maybe it does just needs more food
the strain is Love Potion#1 btw.

 

[Blackvelvet]

Now with the new pics, its not mag def. Epsom salts won't harm the plant. There is no such thing as magnesium toxicity. Don't let ph get above 6.2 in promix. Back to mtf sandmans post, it appears like heat stress.

 

[Nikijad4210]

Epsom salts won't harm the plant. There is no such thing as magnesium toxicity.

Go away, before his plant dies due to your false/incorrect information.

http://www.icmag.com/ic/showthread.php?t=11688
Magnesium (Mg) - Micronutrient and Mobile Element


Magnesium helps supports healthy veins while keeping a healthy leaf production and its structure. Magnesium is significant for chlorophyll-production and enzyme break downs. Magnesium which must be present in relatively large quantities for the plant to survive, but yet not to much to where it will cause the plant to show a toxicity.


Magnesium is one of the easiest deficiencies to tell… the green veins along with the yellowness of the entire surrounding leave is a dead giveaway, but sometimes that’s not always the case here. In case you have one of those where it doesn’t show the green veins, sometimes leaf tips and edges may discolor and curl upward. The growing tips can turn lime green when the deficiency progresses to the top of the plant. The edges will feel like dry and crispy and usually affects the lower leaves in younger plants, then will affect the middle to upper half when it gets older, but It can also happen on older leaves as well. The deficiency will start at the tip then will take over the entire outer left and right sides of the leaves. The inner part will be yellow and or brownish in color, followed by leaves falling without withering. The tips can also twist and turn as well as curving upwards as if you curl your tongues.


Excessive levels of magnesium in your plants will exhibit a buildup of toxic salts that will kill the leaves and lock out other nutrients like Calcium (Ca). Mg can get locked out by having too much Calcium, Chlorine or ammonium in your soil/water.
One of the worst problems a person can have is a magnesium def caused by a ph lockout. By giving it more magnesium to cure the problem when you are thinking you are doing good, but actually you are doing more harm then good. When the plants can’t take in a nutrient because of the ph being off for that element, the plant will not absorb it but it will be in the soil… therefore causing a buildup. A buildup will be noticed by the outer parts of the plant becoming whitish and or a yellowish color. The tips and part way in on the inner leaves will die and feel like glass. Parts affected by Magnesium deficiency are: space between the veins (Interveinal) of older leaves; may begin around interior perimeter of leaf.

Quit talking out of your ass, BV. Try growing pot before you start telling others how to.

 

[Nikijad4210]

the ratio is 3-1.5-4.
feeding 1/4 strength
and they have been veggin for 2-3 weeks now, so maybe it does just needs more food
the strain is Love Potion#1 btw.

Your phosphorus is just 1.5? That's a bit low, dude. I hate to say this, but with you feeding at 1/4 strength with NPK levels that low, especially for Phosphorus, you're actually starving them a bit....And I'm going to stick with Phosphorus deficiency for now, it seems to be the likely culprit at the moment.
Others are saying heat stress, but your light is 2 feet away, that's enough space to keep the high heat it puts off away.
I say by the Phosphorus level, and the strength of food, that it's not getting enough to eat. Do you have anything else you could feed it? You need to give it something with a better ratio, no weaker than a NPK ratio of 5's. Tomato food's NPK ratio is usually around 20-20-20 (a little more or a little less) African Violet food and Orchid food also have higher P numbers, sometimes into the 30's. But for now, to be safe about it, I'd advise you to stick with something like tomato plant food, and start out at 1/4 strength feedings weekly. You need to spend 2 or 3 weeks working up to full strength, don't want to shock the plant.

 

[Guest]

ok i'll feed it a bit more
im stickin with the Pure blend pro. organic w/ lotsa micros
dont like that chemical store bought stuff.
thanks for all the help man

peace

 

[Charles Xavier]

Greetings SmokeNdaHammock

First, allow me to congratulate you on your decision to cultivate.

Second, let me state that I commend your powers of observation and that I wholeheartedly endorse your decision to turn to this community for assistance.

You've been given a plethora of information and your openess to advice is noteworthy. Thanks for allowing the opportunity for me to contribute to an already interesting thread.

To be grown optimally, Love Potion # 1 (especially the Santa Marta phenotypes) requires lower nutrient levels than one would normally provide. This requirement is strictest in the early vegetative stage. The plant is suffering from "nutrient burn".

There is a prevailing notion that one cannot over apply an organic fertilizer. This is a misconception. It can and does happen.

Based on your growing container of choice, I suspect that you have drainage issues. The combination of poor drainage and consistent feeding will manifest itself in some form of nutrient overdose. The solution is to flush your medium.

In order for your fertilizing schedule to be effective, you need to allow 25 to 33 percent runoff by volume of nutrient solution used. With Love Potion #1, I recommend a feeding every third or fourth watering, depending on size of container versus size of plant.

Sincerely,
Charles.

p.s. A ratio of 3-1.5-4 is the same as 30-15-40. Depending on your micro-nutrient profile, this ratio is near optimum for the vegetative stage of Cannabis.

p.p.s. This reply was made in haste, so I may not have addressed some pertinent detail. If clarification is needed, I shall do so at a later junction.

C.X.

 

[MTF-Sandman]

only 75 degrees, fans blowin fresh in/out
HID is 2 feet from tops. i dont think its heat stress

Is that the temps at the canopy? That REALLY looks like heat stress more than anything else to me...as well as a slight underfeeding.

What's the ventilation and RH% in there?

 

[Guest]

Now with the new pics, its not mag def. Epsom salts won't harm the plant. There is no such thing as magnesium toxicity. Don't let ph get above 6.2 in promix. Back to mtf sandmans post, it appears like heat stress.

You have got to be kidding me? That post alone should have you banned once again!

 

[emmy75]

man thats def heat stress. ive had that before plenty of times living in a place that can get up to 90 during winter. NICE!! anway just shut off the lights for a while and give the room a good spray. thats what i always did. nothing serious.

 

[Guest]

damn almost every1 is sayin heat stress..
temps are around 75, light 2 feet away, fans blowing fresh air in, stale out.. how could it be heat stress with all that?

could it be too dry in there?, the humidity is only maybe 15% or so(no guage), i keep it well ventilated. that could cause the leaves to dry out and curl right.
maybe its a combo of both, heat and dry air.

Hey Charles,
Its good to see you here, ive read more than a few of your posts and realize you really know what your talking about. I do not think its nutrient burn nor a drainage issue however, because i have been givin them 1/4 str. doses every other watering, or every 3 days or so. I have been pretty cautious with overfeeding. I use 3gal grow bags, have you noticed people having drainage problems with these?
Could you clarify your reasoning on those issues?
thanks

peace

 

[Charles Xavier]

Greetings SmokeNdaHammock

It's good to be seen.

Nutrient strength is relative. Quarter strength does not mean much, if at quarter strength the EC turns out to be 2.0 ms/cm (1000 ppm at .5 conversion; 1400 ppm at .7 conversion). Now I'm certain that this is not the case and I only use that figure as an example, but it should be made plain that one cannot be sure of whether the EC of a nutrient solution is acceptable by relying on an estimated dosage. If you are unsure as to what the EC of the nutrient solution is, then your alternative is to rely on the plants to tell you.

Heat stress is actually the manifestation of a plant's inability to maintain turgidity on a cellular level. It is based on osmotic imbalance. The role that temperature plays is in the regulation of the metabolic processes. If the metabolic rate is too high (high temperatures) or water availability is too low (dry substrate or high EC), then the symptoms of heat stress appear. Since it is ascertained that high temperature is not the issue, then that leaves dry substrate or high EC as possible culprits.

Dry substrate is indicated by wilt. High EC is indicated by the "clawing" of the leaf (either upwards or down). I came to my conclusion even before this step and as outlined in my previous post.

Growbags are not well designed for the amount of moving neccessary to properly water plants when employing the constant fertilizing method. They generally tear if consistently moved while filled with wet substrate. The rigidity of a plastic pot is more condusive to proper drainage.

Again, when using the constant fertilizing method, it is imperative that you water to drain. You must either water in an appropriate area (eg bathtub) or you must move the plant containers to ensure that they are not sitting in a pool of stagnant water. Excess water must be cleared promptly so as not to court humidity (pathogenic) issues or worse, the uptake of a salt heavy solution due to the capillary action of the substrate. In any case moving the containers needs be done, and grow bags are not the most suitable for this.

1/4 str. doses every other watering, or every 3 days or so....SmokeNdaHammock

This quote tells the tale well. Fertilizing a high EC sensitive strain in a three gallon container every three days is overfertilization.

Sincerely,
Charles.

 

[Guest]

ok, im convinced. ill cut back on feedings
used to growing northern lights, figured id be in for a little challenge w/ this one.
i gotta stick with the growbags thou, too late now. plus i kinda like em cuz i can squeeze a few more plants under the light with em.

thanks for the info charles

 

[MTF-Sandman]

could it be too dry in there?, the humidity is only maybe 15% or so(no guage), i keep it well ventilated. that could cause the leaves to dry out and curl right.
maybe its a combo of both, heat and dry air.

That absolutely could be the cause...heat stress is basically just a form of moisture stress - the plant is making the leaves surface area smaller by curling them up to try to conserve moisture. So raise the RH to around 40-50% for flowering or 50-60% for vegging and water them a little more often with weaker nutes.

BTW, nute excess can cause the same response in the plant since the plant will try to slow the uptake by the roots by reducing transpiration via less leaf surface area (ie. tacoing leaves).