Flowering deficiency? What do you think IC mag

[Creeperpark]

Creeperpark what do you recommend PH'ing your water to? Some people suggest that because peat is technically soilless, you should ph for that value, but others believe once you add compost and amendments to it that it actually becomes soil soil, and therefore in a different ph range so to speak. What do u think?

For peat grows I use just enough cal-mag and nutrients in pure water for a 6.2 pH. Using peat that's heavily amended with organic amendments, I only use pure rainwater without anything. Rainwater is in the 5.5 pH range and when mixed with the organic soil it keeps the range that's best for microbes populations. After all its rainwater only. When using synthetics one needs to be very consistent with water and pH for best nutrient exposure. Using synthetics one should never use pure water only because it can break or disrupt the nutrient chain or sequence.

 

[f-e]

FE I usually get some K deficiency when humidity gets super low like it is this time of year. Ive read it is a VPD thing. So I think it's safe to say there is a little K deficiency compounded with whatever else is going on. It's interesting u say that Mg can block uptake of K and Ca, especially since I havent seen any improvement since I fed with Mg, if anything, maybe even worsening of symptoms. It's something I need to do some more reading on.

Mg is sometimes just said to antagonise K, but Ca is in that group. Outside of the usual suspects, Mg can also effect other metals. F-e which isn't happening here, but also Mo and it does show up as similar to Mg sometimes. An Mo problem is likely caused by environmental influences rather than a lack in the feed, as so little is used. It's perhaps not worth thinking about.

There is a trend towards Mg and N in this thread. Mg failed. I would try N. It wasn't my first choice, but I can't ignore it.

 

[Creeperpark]

When using a peat mix like pro-mix hp, or sunshine one needs to keep the water and nutrients steady without disruptions. That way the plant has the same chemistry without any imbalances. When one gives different water and nutrient ECs to the plant the plant gets mixed up or confused so to speak. When you keep your grow steady and consistent the plant adopts a nutrient regime that is best suited for it and takes what it needs. Once the nutrient chain is broken it is super hard to get the plant back where it was.

 

[GoatCheese]

That's surely a more sanitary way to do it. But to get a real feel for the earth.. stick a finger in it.

Usually, cause i have to grow in fairly small containers, my soil gets quite packed and filled with roots so there's no sticking your finger in it.It's too dense.

When you learn to estimate the moisture content by the feel with your hands, you can actually feel if there's still alot of moisture in the bottom of the container when you rock it from side to side ,thou the surface may feel and look quite dry. In which case you can only water the pot a little bit to keep the surface moist and allow the lower part of the container to dry out abit before the next larger watering. Sometimes fans moving the air can make the surface feel dry enough for a good watering but there can still be quite alot of moisture in the bottom half of the container and so it can lead to over watering if you're not paying attention.

 

[vtgirl]

Don't allow discharge and your nutrients will last longer. Size matters friend when it comes to plant size and end weight of the plant. The main difference is water management between the two. Watering a 1 gallon every day or every other day and 5 gallon every 3 to 7 days depending on the substrate makes a big difference. Larger organic mixes can feed and supply way more nutrients than is needed for a growing cycle while 1-gallon containers can't. Here's photo of organic water only grow.

Yar bars
lots of good info
Good advice

 

[HempKat]

Yeah most damage that shows up in leaves whether it be deficiency, ph imbalance or environmental issues won't correct itself when you fix the problem. That being said I have seen cases of N deficiency that was caught early where the leaves were just turning light green but not yet yellow and then when the deficiency was corrected the lighter green leaves darkened up again. Once they get as yellow as the ones in your pics they don't revert back.

Now since this all seems to happen each time during the first couple of weeks of flower (the stretch phase) You might want to try something I always did. When I switch to 12/12 I wouldn't just switch straight away to nothing but flower nutrients. I knew the first two to three weeks of flower (the stretch phase) there would be a fair explosion of new growth and so for the first two weeks I would give a 50/50 mix of veg and flower nutrients and in the third week I'd taper it down to 1/4th veg nutrients and 3/4ths flower nutrients and then from week 4 on just flower nutrients. The reasoning I used was that this explosion of new growth mainly being new leaves, stems and a thickening and lengthening of the stalk there would still be a fairly high demand for Nitrogen. Flower growth is mainly covered by Potassium and phosphorous and since some flower development was also occurring at this time it made sense to provide a good amount of flower nutrients as well. By the third week of 12/12 stretch is starting to slow so it made sense to me to reduce the veg nutrients and around that point flowers are starting to develop pretty good so it made sense the the flower nutrients should be increased too. By week 4 and beyond it's basically all flower growth and since most flower nutrient mixes have some Nitrogen it made sense that it should be all flower nutrients from that point on. This is something that worked well for me but since were not entirely sure what's happening in your case I can't promise you it will solve your problem. Again though what caught my attention was that you say this seems to happen consistently at the 2 week point of 12/12 which fits with the reasoning I used on my feeding routine.

There are two other things to take a look at though the main one being the low humidity in the 30% range is pretty low, that's about half what it should be this could be potentially affecting the way your plants are taking up nutrient and water and perhaps that's playing a role here. In nature the plants do most of their veg growth in spring when temps are cooler and humidity is generally lower depending on the rainfall indoors however and since the amount of moisture is more steady from watering it's not unusual for humidity to be as low as in the 30's. Also since it's still cool in spring sometimes people are still running heat which can dry out the air. What I'm trying to say is that during veg growth the plants might be better able to handle a lower the ideal humidity then it can in flower. The traditional flower period is in the late summer when humidity is usually pretty high so maybe this explains why you don't see problems cropping up until flower? There are ways to boost humidity though to see if you can improve things. One simple trick people use is to just hang a damp cloth in the room and keep wetting it as it dries out or better yet change it out for a new damp cloth as it dries. Another more expensive option would be to add a humidifier to your grow space. These are just guess though since I never really had that much of a problem with humidity.

The other issue that caught my eye was you said that you're PHing your water between 6.0 and 6.3 6.3 is on the very low end of what is considered okay for soil. The ideal level is 6.5. At 6.3 Nitrogen and Potassium still gets thru but Calcium, Magnesium and Phosphorous do not. When it gets down to 6.0 the Nitrogen and Potassium also get locked out. Now it's also important on where you're taking that reading from, if that's just the water before adding anything and before going into the soil, those values could mean nothing the nutrients you add or the nutrients in the soil could be making the ph higher or lower. Lower would be bad if the starting point is 6.0 to 6.3 higher would be good if it was just a little higher up to 6.5. Once you get above 6.5 though then you start locking out Iron and Manganese everything else is okay though until you get to 7.0 or higher but ideally you should keep it at 6.8 at the highest with 6.5 being the sweet spot. Really what you need to be measuring is the run off or the soil in the root zone as this is more reflective of the PH the plant sees.

One final thing and I don't think this has to do with your leaf issues but you mentioned your soil tends to get hydrophobic. I'm not familiar with the Coots Mix you mention but most soil mixes people buy even organic have little to no perlite and/or vermiculite in them to help improve drainage/aeration your soil going hydrophobic might be an indication that you need to add more perlite and/or vermiculite to improve drainage and that might stop your soil from turning into a hard brick?

 

[TanzanianMagic]

So i have 1 bodhi lemon thai indy and 2 bodhi sun ra (sfv x wookie). All 3 plants are in an organic soil mix using the coots mix from buildasoil. The 2 sun ra are in 1 gallon plastic pots, the lemon thai is in 3 gallon grow bag. 600w hps, 3x3 tent. 77f humidity has been high 30s. I know the humidity is not ideal, but it's all I have to work with right now. I was watering every 3 to 4 days using bubbled tap water. I was ph'ing my water from 6.0 to 6.3.

Everything is perfect and lush and green until week 2 and its pissing me off. At this rate all my leaves will be gone in two weeks, and we cant let that happen.

The low pH is locking out mobile nutrients, most likely Mg, possibly N. pH in organic mixes should be 7.0, for the medium, and the liquid nutrients. The aerobic microbes which break down the organic nutrients can thrive in 6.0 to 8.0 pH, so you don't have to worry about pH swings.

Then, the 3 gallon in soil are possibly too small. 1 gallon per foot of expected growth is the minimum. So a 6 foot plant as mentioned on the packaging should have a 6 gallon pot - more is better.

 

[BobChronic6505]

HempKat and tanzanianmagic thanks for your responses. The PH is definitely something I can work to change.

 

[HempKat]

HempKat and tanzanianmagic thanks for your responses. The PH is definitely something I can work to change.

No problem, if I remember correctly Tanzanianmagic is experienced with organic mixes where I pretty much just grow in soil with a few amendments for drainage/aeration and some dolomite lime to act as a ph buffer and a source of calcium and magnesium. Since what you do is more of an organic mix you'd probably do better to follow his advice then mine. Creeperpark and F-e are good ones to listen to as well. That's not to say anyone else isn't good, you've basically been getting good advice from everyone.

 

[BobChronic6505]

So I believe I may have found a potential culprit. I've did some digging (puns intended) and snooping, and I believe I've used way too much compost, and way too little aeration. The soil has been turning to MUD every time I've watered, and I have definitely been overwatering these plants. They've probably been drowning ever since they were transplanted and flipped to flower.


I think the best think to do is start over. I'm going to remix some coots up again, this time with considerably less compost, more peat, more aeration. 10x the pot size in flower. Less water. We may even have to utilize some soil testing to really get down to the bottom of things

 

[Creeperpark]

So I believe I may have found a potential culprit. I've did some digging (puns intended) and snooping, and I believe I've used way too much compost, and way too little aeration. The soil has been turning to MUD every time I've watered, and I have definitely been overwatering these plants. They've probably been drowning ever since they were transplanted and flipped to flower.


I think the best think to do is start over. I'm going to remix some coots up again, this time with considerably less compost, more peat, more aeration. 10x the pot size in flower. Less water. We may even have to utilize some soil testing to really get down to the bottom of things

Bob you've done a good job working out issues in this grow. Every garden teaches something different and is our teacher if we are willing to learn. Even today I still learn something new from every grow. Winners never Quit! Thanks for sharing.

 

[BobChronic6505]

Bob you've done a good job working out issues in this grow. Every garden teaches something different and is our teacher if we are willing to learn. Even today I still learn something new from every grow. Winners never Quit! Thanks for sharing.

I use the hell out of the search feature and read thread after thread, and nobody ever posts a resolution. I want to comment on old ass threads and ask ppl if they ever fixed their issue and how they did it.

So while the mud discovery has provided some answers, theres still a lot of questions !!!

 

[f-e]

If being too wet has reduced N uptake, I wouldn't use a bigger pot. That's more water, and if you have to produce some runoff, that might be so much water they can't drink it for a week (10x bigger)
I see the room is 25c. Is the feed reasonably warm? Cold wet feet would be a good find, in regards to having found a problem that could cause this. If I used water straight from the tap, I would probably kill them, mid winter.

 

[BobChronic6505]

If being too wet has reduced N uptake, I wouldn't use a bigger pot. That's more water, and if you have to produce some runoff, that might be so much water they can't drink it for a week (10x bigger)
I see the room is 25c. Is the feed reasonably warm? Cold wet feet would be a good find, in regards to having found a problem that could cause this. If I used water straight from the tap, I would probably kill them, mid winter.

Man I like small container growing for a variety of reasons, but all the organic shit I read says I need a minimum of 15 gallons. I'm going to try 7 to 10 gallons next. A few ppl in here suggested bigger pots also. You do have a valid point with watering, but I'm hoping with the added aeration and less compost will help. Buildasoil recommends watering 1/10th of your container size, which sounds pretty reasonable I think?

 

[BobChronic6505]

f-e I didnt rly think about cold water fucking them up, but I'd say the water is 60ish degree F so yeah its cold