Heavy Yellowing in Flower

[brightskies]

I FILLED OUT A FORM- SEE BELOW. PICS TOO...

I'm growing a sativa (I think) in rockwool inside of 3 gal. pots and hand watering. This yellowing really started showing in wk 3 of flower. It's on all of the plants. A lot of the leaves have terrible looking sores on them and feel really limp. A lot of eagle claw leaves too. I'm in week 6 now and have 2 weeks left. The yellowing is starting to get into the bud leaves now and I'm getting a little worried. My friend grows the same strain and has almost NO yellowing at finish and has about 40% more yield at this point. But, he knows what he's doing- I'm still pretty new! I had a somewhat similar thing happen to my last grow only to buy a PH meter and find that my tap water is 8.1. I've run at 5.8 the entire time this time around!

I'm guessing it's probably a combination of things:

- The main problem is probably over watering. I'm finishing in 3 gallon pots filled with rockwool. The roots look kind of red/brown but aren't slimy and don't smell. I've used Cannazyme from the start. I only water when it is getting close to dry and water until I feel a little heaviness in the pot. I'd guess that I'm giving them maybe 30-40 oz of water every 2-3 days. There's never any runoff. I've tried to get them a little bit drier before watering, only to have a couple get stressed looking from drying out too much. A couple weeks ago I saw a few small, fresh, white roots on a couple of rootballs, but not anymore. My friend grows this strain in 2 gal pots and waters almost every day just a little amount, maybe 15 ounces. I haven't been able to look at his roots yet.

- At 2 weeks of flower they were "treated" to 2 new XXXL 1000W reflectors versus the mover with one 1000 watt lamp. Maybe they got a little confused when the "sun" got a LOT brighter right after fall started.

- I totally redesigned my room when I got the new lights and worked through two dark periods doing minor construction with my green led on. I had a couple of burned leaves and some shaky light cycles for a few days until I got everything sorted out. Add in some moderate temperature inconsistencies.

- There's no nitrogen in this Canna Aquaflora (my friend uses a fertilizer with a tiny bit of N in it).

- Maybe at least some of it is part of the natural cycle.

Here's a few pictures, I've been removing quite a few dead leaves every day for the last couple of weeks:

And a typical rootball showing a little brown/red:

I know it's a little late now, but is there something I can do to help? What about next time? Here's the form:


Strain of Mj? SATIVA?
Hydroponic or soil? HYDRO
From seed or clone? CLONES
Age of plant in question? 6 WEEKS 12/12
What stage (Veg/Flower; how many days into)? FLOWER, 42 DAYS
Medium (Soil, Rockwool, Hydroton etc.)? ROCKWOOL
Container/Pot size? 1 gal 1 week, 2 gal 1 week, 3 gal since then
Have they been transplanted, if so how long ago? see above
Water runoff Ph? HAND WATERING- NEVER HAD ANY RUNOFF
Nutrients added? CANNA LINE- COMPLETE, PER THE SCHEDULE, EXCEPT BOOST- I'M USING THAT AT THE MIDDLE OF THE RECOMMENDED RANGE.
Ratios of nutrients (N% P% K%)? O-4-4
Feeding schedule? EVERY HAND WATERING, EVERY2-3 DAYS
When were they last fed/watered? IN THE LAST 1-3 DAYS
How are you determining when to feed/water (weight, wilting, etc.)? WEIGHT, WILTING ON ACCIDENT A COUPLE TIMES ON A COUPLE PLANTS
TDS/EC/PPM? PER CANNA SCHEDULE- NOW I'M AT 900 PPM
Tap/RO/Distilled water? TAP
Ph before and after adding nutrients? 8.1 BEFORE, 6.4 AFTER
Is your Ph equipment properly calibrated? YES, I HAVE 2 MILWAUKEEE DIGITAL SM?? MULTI METERS AND HIGH & LOW TEST SOLUTION AND KEEP THE SENSOR CLEANED & SUBMERGED IN THE STORAGE SOLUTION
Light intensity/Age of bulb/Wattage? TWO 1000 W, ONE NEW, ONE HAS ABOUT 1000 HRS
Distance to the canopy? ABOUT 5-10 INCHES
Temps at canopy? 78
Temps at root zone or reservoir? 75
Day/Night temps (Min.-Max.)? 78/69
Current air flow (CFM)? CAN FAN 8" MAX cfm= ??? (PLENTY)
Is there air blowing directly onto plant? OSCILLATING FAN ON WALL 4 FEET AWAY ON SPEED 2
Using CO2? NO
Relative humidity? 32-40% (DEHUMIDIFIER)
Growing technique ?????
Has plant recently been pruned, clones taken, fimmed or pinched? NO
Pests? NO
Chemicals used to irradicate? N/A


THANKS FOR TAKING THE TIME!

 

[hydr1]

overwatering and the plant is eating all the N from the leaves...prob from the flushing and its towards the end...alot of plants eat up leave sat the end...but not week 3.

 

[brightskies]

overwatering and the plant is eating all the N from the leaves...prob from the flushing and its towards the end...alot of plants eat up leave sat the end...but not week 3.

I haven't flushed them yet.

 

[brightskies]

What are your thoughts on switching to a smaller 2 gal pot? They are in 3 gal pots now.

For the next go-round should I be giving them less water each time and water more often, daily even? This is only my second time growing in rockwool instead of dirt. Thanks for the help!

 

[sanke]

DO NOT transplant them into a smaller pot thats forsure.

Like hydr1 said, plants near the end of their flowering cycle will sometimes look like this, however during week 3 this is not normal. Looks like a lack of N to me... Also the leaves shouldnt be all droopy...

 

[maryj315]

So you are growing in rock wool but watering it like it is soil. And what is really crazy with a little tinkering it looks like it will work.

Looks like you might have some lockouts due to salt concentrations in your medium try a good run off every feeding or an occasional flush.

I am sure you are keen to using this method of growing, I thought you were supposed to flood rock wool several times daily.

Perhaps someone with more knowledge will help.

Mj

 

[hydr1]

these plants are in rockwool.....so its alot diff from soil...if you are vegging for only a week and doing a sea of green you can get away with 2 gallon pots...you would need to water 2-3 times a day though.

research H202 (hydrogen peroxide)....find a reciepe for a solution...that will get more air to the roots and might clear up the mild root rot you have going on.


do you use the cannazyme every watering? I recently red that you should just use that when you water with plain P/hd water maybee once a week.

do you feed everyday?

The yellowing leaves are 100% nitrogen def....and you shouldnt need nitrogen in flower cycle and shouldnt add it at this point...maybee give more N in the veg cycle and transition cycle before flower next run.

The spots and other blemishes look like they could be splashed nutes on the leaves...be carefull when you water and dont wanter or spray anything with the lights on...the droplets produce magnifying effects and will cause inconsistant burns

 

[brightskies]

DO NOT transplant them into a smaller pot thats forsure...

I meant for the next grow. Sorry I wasn't more clear!

I'm not really stuck on rockwool, I just copied someone and got half-way decent results one time (this crop shouldn't be too bad either- when all is said and done). I want to get a couple of EXCELLENT grows under my belt before I explore more sophisticated growing methods.

I'm feeding full strength at EVERY watering and never having any runoff. Does that practice allow salts to accumulate and inhibit the uptake of nutrients? Shoul I water with plain water once in a while. Or, is that strain dependent and/or personal preference?

In soil, I always watered until I had a little runoff to encourage deep root systems. But, that seems like WAY too much water for rockwool in 3 gal pots. If I water until I get runoff with rockwool, it takes about 7 days before it needs watering again. Isn't that even worse than what I'm doing now?

Thanks for all of the help. Please give me more of your thoughts on proper watering with rockwool in pots.

 

[brightskies]

... do you use the cannazyme every watering? I recently red that you should just use that when you water with plain P/hd water maybee once a week. ...

The Cannazyme instructions state to use it at least weekly, but say its preferred to use it continuously. It says not to use it with any other hydrogen peroxide product. I imagine I would probably be a lot worse off if I hadn't used it at all.

The spots and other blemishes look like they could be splashed nutes on the leaves...be carefull when you water and dont wanter or spray anything with the lights on...the droplets produce magnifying effects and will cause inconsistant burns

That's very likely. I hadn't even considered that.

 

[B.C.]

I agree with the *overwatering, but all in all, I think they'll be fine in the end. Yer at six weeks now with plenty of green leaves left to finish them off.

Next time, use yer grow nutes through the stretch in the first part of flower, then go with flower nutes. Every strain will be a lil bit different about this sorta thing, so it helps ta work with a strain fera while and tweek it to that particular one.

Yuv done a great job for this bein only yer second grow! Every round yul learn more, so hang in there. It'll jus keeps better an better! Good luck to ya, and enjoy that harvest! BC

 

[brightskies]

Next time, use yer grow nutes through the stretch in the first part of flower, then go with flower nutes. ... BC

That answered a question I'd been meaning to ask. I just assumed you switch the nutes the day you switch the lights. But I had been wondering lately what you're supposed to do.

Thanks for the encouragement, I've been a little worried about it lately.

 

[hydr1]

most two part ferts suggest using both at half strength for the transistion period...first week of flower.

 

[brightskies]

On my next grow, should I mix in some of the water repellent type of rockwool together with the regular rockwool so that there would be less water retention in the pot? This may help me to more easily avoid the light root-rot and may also make it easier to flush my plants without having them wet for 5 days. Maybe a 50/50 mix? I think the repellent rockwool acts as a kind of non- absorbing filler media. Has anyone ever used it?

 

[brightskies]

most two part ferts suggest using both at half strength for the transistion period...first week of flower.

Thanks! So obvious I never thought of it.

 

[brightskies]

I flushed them a few days ago with clear water. The initial runoff was almost as dark as Coca-Cola and the ppm's were way off the 2000 max scale on my digital meter. It took a few gallons of clear water in each pot to get the ppm's down to about 300.

This was the first runoff these 3 gal rockwool filled pots have seen (now at 7 wks. flower). Next time I'm going to use 2 gal. pots and flush them with clear water 2 or 3 times during the grow. Although the pots are pretty waterlogged right now, everything seems pretty stable and the flowers are still growing. All is not lost...

 

[brightskies]

Thanks for taking a look. The pics are from about wk 5 1/2 of flower. The heavy yellowing and leaf drop started at wk 3 of flower. I'm thinking it was nutrient lockout because of heavy concentrations of nutrients in the rockwool. I always gave full strength nutrients at every feeding and never allowed any runoff.

I'm less than a week from chop and ALL of the fan leaves are gone. One plant has extreme yellowing of the bud leaves too, but the others don't. The buds are still swelling though.

I'm not so sure anymore if I had any root-rot. The roots have really lightened up in color since I flushed all of the dark ferts out of the pots. They are not slimy at all and don't have any foul odor.