yellow leaves

[libby]

could someone identify this problem, sorry for the poor photos, this my first ever attempt to post on any forum.
jack herer, in rockwool. canna veg, turned last week, now in flower food, canna, but these started to yellow 4-5 weeks ago.
My friend has grown before with good results, this time however, low temps have been a problem, and losing power on the odd occasion, nothing else, we think.the roots were potbound a while back, but since, repotted.they seem slow to grow,under a 6oo hps,only 6 plants in a small area, 3 1/2 foot square.
will these still fruit??

I know you need more info, in what order ? thanks for taking the time to read.

 

[Guest]

Fill out the form that mynameistich has posted in the infirmary and one of the plant doctors will be right with you. In the mean time...care for a magazine? What is your water's ph? The ph of the run off?

 

[libby]

HYDROPONICS/Aero Ponics

What system are you running? (DWC? Ebb flow? Aero? Water Farm? Flood Tables? and so on... hand water when lightish pot
What STRAIN are you growing?... jack herer
What was the establishing technique? (Were the seed or clone?)...seed
What is the age of your plants?... 12 week
How tall are the plants? ...14-16 inch
What PHASE are the plants in? (seedling, vegetative or flower) are the plants in?...in flower for last 4-5 days
What Technique are you using?
What substrate/medium are you using?(Hydroton, RockWool etc.)...rockwool
What is the Water temperature? don't know.. not too cool, just warm ?
What color are your roots? White? Brown? Are your roots slimy?..good white roots
What Nutrient's are you using? How much of each if using multiple?...canna..
What is the TDS/EC/PPM you are using?...1100 ppm
What is the pH of the "Tank"... 6.3 when fed
Are you sure your calibration is correct on your equiptment?... new
When was your last watering?...3 days ago
What is your water temps?... don't know.. but allwed to heat slighlty, airing cupboard
When was your last feeding change? (ie. grow-bloom-micro-additional)..5 daya ago... well after this condition occured
How often do you clean your system: example: Flush out water replace with clean water and nutrients?... flushed every 2 week..new food everytime..
What size bulb are you using? ...600hps
What is the distance to the canopy?...12 inch
What is your RH Factor(Relative Humidity)? ...don't know
What is the canopy temperature?...72-74
What is the Day/Night Temp? (Include flucutaion range)..day temp as above, night temp, up down..up down
What is the current Air Flow? (cfm etc.) .. very low sometimes nil
Is the fan blowing directly at plants? at hood.. WHEN on, rarely
Is your water HARD or SOFT?...soft
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water? ...tap
Has plant been recently pruned, cloned off of or pinched... yes, after this cond occured
Have any pest chemicals been used? If so, What and When? ... nil
Are plant's infected with pest's ...no...

to add too this, when this started, 4-5 week ago, for 8 days after this, only plain water was applied to see if the problem could be washed away. then food at about 1100ppm since apart from stated flushing

 

[MynameStitch]

From the pics, I can't tell the details because of how bad the pictures are..... are the veins on the plant green while the leaves yellow?

Your plants are in rockwool and you hand water? How much rockwool is in that pot??

Which nutrient you using? I know canna, but which line? they have many nutrients.....

6.3 is right along the line of being high for rockwool, you will need to get some pH down and use it when you mix your nutrients....

what is the pH of your tap water?
Are you following the dosage on the back of cannas bottle?

2 prolems could be the cause, for one they ARE lacking a nutrient(s) most defiantly a micronutrient problem going on. I can't tell which one due to the pictures being bad.

it may be magnesium it looks like......
or it could be iron.... don't know yet cause the pics are very bad
Can you get some better pictures?

I would get your pH corrected when you get this problem fixed so you can have the best possibly absorption for the plant.

5.5 to 6.3 is the range, you are right on the boarder of it going overboard and I would get it in the range of 5.5 to 5.8 or 5.5 to 6.0

 

[libby]

thanks for your reply mynamestitch, yes the plants mostly have green veins amongst the yellow leaves, mentioned this to my mate, as from your chart, is could be a mag deficiency, epsom?

will get better photos, this was just an emergency photo set/

The rockwool is about a gallon and a half.

the canna is A B... don't know if that's makes sense to you

You may be spot on with the ph as he as been 'assuming' it's right ( i know!)

so, for now, would you say, add epsom, and sort the ph out ?

Shall sort close ups out, please bear with me, this is MUCH appreciated.

 

[HeadyPete]

For now, add nothing and sort out the ph. See if the leaves green up after ph is correct. There could be plenty of nutes but they are locked up and not available to the plant, so adding more would put you closer to an overfert situation without you even knowing it.

Let's see some better pix before we proceed with any other remedies. Do you have a real cam and not a cellphone to take photos? A tripod would be even better for crystal clear close shots. Try some flash too.

It sure does appear to be mag def, but one step at a time.

 

[Guest]

See, libby, I told you the doctors would be right with you. Lucky you...you got 2 of the best in the business here to work on your problem. Now get them some good pics and I bet you green up in no time.

 

[libby]

Heady, thanks for helping, when you said do not add anything, and i mentioned epsom, i realised i was wrong, thanks for the reassurance.

Bit of good/bad news?

He has called round tonight, and told me, he`s nipped off his yellowing leaves, because he can see new green growth coming out of the top.

He will still have the same problem ? yes.

weve spoken tonight, before findind your response and agreed, hes washed in tap water of at least 7 ph.

We have pulled the plants out of the pot, and found the bottom of OUR rockwool, was holding water, uncirculated, (high ph?) for days.
Are we on the right track?

Heady, can't thank you enough, and stitch,

Old Fool, cheers, your ph diagnoses was spot on

Stitch, thanks, he's never realised how important ph is.










What a cheerful site,thanks to all concerned, even those who heid back, letting the experts do their job.

If things change, or not, will sort the photo,s for our/ my learning, Thanks.

 

[Guest]

I'm no hydro guy but if your rockwool has been holding water, I'd check on root rot. Again, I got NO clue on hydro, just tossing that out. Stitch or Pete will, hopefully, correct me. Use the whip again, Stitch...PLEASE???

 

[HeadyPete]

Well I'll leave the whipping to Ms Stitch but you are absolutely correct that uncirculating, oxygenless water will indeed cause root rot.

Rockwool should be free to absorb what it can and freely drain what it cannot. Roots sitting in a pool of water is no good regardless of medium. Roots need oxygen and being submerged in stagnant water deprives them of this and they die and rot. That's the big issue more than high ph.

DWC works because the bubbler is always providing oxygen to the roots, by circulating the water and the water picking up fresh O2. If a DWC system loses power, those plants will not live long in that still water.

 

[MynameStitch]

lol, sorry Old Fool like petey has said and he is correct. You lucked out again on the beating lol.

My whip is getting useless and lonely

muhahahahahha

Just because he removes the leaves does not mean the problem is fixed, it will come back until he fixes the problem that caused it. I would always let the plant try to drop leaves and never cut them off, unless you have no other choice, if it's dying off and about to fall or you know it's going to, yes remove it.

If the leaves can't come off easily, leave them there, the plant is still taking nutrients from the leaves and putting them elsewhere on the plant, so it's like removing your storage of bottled water and dumping it out.