Weirdly shrivelled leaves on one strain

Hi RIU!

I have some strangely shrivelled lower leaves on two of my plants - both the same strain. One is showing them only on the lower leaves (although these were showing the same problem when the affected leaves were the top leaves). The problem seems to be worsening. My gut instinct is overfert, but I am a noob so I defer to the experts.

Medium: Coco coir
Feed: Light feeding schedule of Canna Coco a&b plus root tonic at normal strength
Schedule: Watering every other day, sometimes a two day gap between waterings. Feed with every watering.
Light: 400W MH, about 2 feet away from plant tops.
Strain affected: Super Lemon Haze

Here is a pic:

New growth is fine. Everything looks great.You have no problem at this time.
Keep going as you are.

That is a Sativa. You are wise to use the light feeding as they can be nutrient fussy. Once you get to flowering, be aware that it will flower longer then 8-9 weeks. I would not switch to bloom nutrients until the "stretch" has about ended. Say around 6+ weeks....In stretch she could as much as triple in size, so plant ahead for when to flip to flower.

Nice looking!

Thanks Doc! Has put my mind at ease somewhat. I should mention though, this is one of two SLH plants, the other is showing similar symptoms on the newer leaves. Is it just a slightly mutated set of leaves perhaps?

I upped the feed last time to 20ml per 10 litres (the guide says 19) and they all seemed to love it. I am wondering whether to give them a cautious watering at 23ml per 10 litres, which is the "normal" feed schedule. If they react badly I will back off of course, but they seem to be enjoying the extra feed.

Quick question about your advice - 6+ weeks *into* the flowering period is when to introduce bloom nutes? Just want to be clear.

Grow guide I am going by says that bloom nute introduction should be after the stretch or when the first flowers appear, can it take six weeks of 12/12 for that to happen? I am aware that it is likely a ten week flowering process for SLH, so I suppose six weeks isn't that extreme, just raised an eyebrow is all.

Wilco on the size watch - hadn't realised sativas could triple in size during flowering, I was banking on double. I will plan accordingly. Thanks again!

Yeah, start bloom nutes later for that one. 6 weeks is where I would start them as the stretch in that one will go that long....It can be nutrient tolerant, but some heavy sativa pheno's may not be as much. I might give it a "spike" of P&K, one time at 8 weeks and not too much....maybe that's a trick for later on in future grows.....just finish this one for now and worry about that later.
I might say that will go 11+ to 12 weeks to the best finish.

I would not yet up the ratio of nutrient to full strength till maybe you have 5 nodes. Your starting 3 now.
If you begin to see yellowing/browning at the very tips of the leaves. Back off the nutes a tad,,,like where you are now and stay there, unless it shows it on the new growth after 7 more days. If so, then I would back off another tick.

You're doing GOOD.....show us more down the road!

Umm... there's no way you wait 6 weeks in flower to add bloom nutes. Am I not reading right? Generally stretch is done and flowers form in 2-3 weeks. I must be miss reading this post cause no bloom for 6 weeks is going to give terrible results. If you keep feeding high N veg nutes in flower for 6 weeks your buds will not form properly from lack of P and K.

Sent from Northern Colorado.

Merlin,,,you missed that it is a Sativa Dominate strain......longer stretch!
I won't add bloom nutes to "8" week flower strains till the beginning of week 4.....You really don't need the extra P&K till then ( I do give them a SMALL spike at the flip to help induce) or reduce the N till then either. This will prevent early high P&K troubles.

The wait till week 6 is due to it being a Sativa and that it runs 10+ weeks and stretch's longer.....Although,,,you could switch to bloom nutes at 5 weeks and most likely still be good...Hell, you could mix the 2 (veg and bloom) 50/50 at week 5 and be very sure.

Yo Dr.Who how are you so certain that this is sativa dominant? The leaves seem fairly wide to me. I'm not questioning your judgement I just want to learn a little more about the tell-tale signs.

It's super lemon haze so it is sativa dominant, that is correct. The canna guide says to wait until stretch is over or first buds show to switch to bloom nutes, whichever comes first. I will go with that for all my plants, as doing that allows for any variation in genetics. I am also growing some more indica dominant strains.

Merlin34 said:

Umm... there's no way you wait 6 weeks in flower to add bloom nutes. Am I not reading right? Generally stretch is done and flowers form in 2-3 weeks. I must be miss reading this post cause no bloom for 6 weeks is going to give terrible results. If you keep feeding high N veg nutes in flower for 6 weeks your buds will not form properly from lack of P and K.

Sent from Northern Colorado.

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Ummm...so called bloom nutes are only good at draining your wallet. Not growing big buds. They far to often cause much more harm than good from being abused. A 3-1-2 ration with balanced micros and trace elements is all cannabis, along with most container grown annuals, need from start to finish.
And Flash I would back off the waterings a bit. I see no reason a plant that size in that big of a container needs watered every other day, just asking for mold, fungus gnat and root rot among other things Water until you get a decent amout of runoff from the bottom of the pots and do not water again until the pots feel light. Also feeding every watering, especially in coco is also asking for salt build up issues. Feed, water, water.....

Alexander Supertramp said:

Ummm...so called bloom nutes are only good at draining your wallet. Not growing big buds. They far to often cause much more harm than good from being abused. A 3-1-2 ration with balanced micros and trace elements is all cannabis, along with most container grown annuals, need from start to finish.
And Flash I would back off the waterings a bit. I see no reason a plant that size in that big of a container needs watered every other day, just asking for mold, fungus gnat and root rot among other things Water until you get a decent amout of runoff from the bottom of the pots and do not water again until the pots feel light. Also feeding every watering, especially in coco is also asking for salt build up issues. Feed, water, water.....

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Thanks Alexander this sounds like sound advice. As far as the watering schedule goes, I have been checking the pots - I've also not been watering until runoff as yet, as they are (were) quite small. I think now is the time to ramp up to runoff feedings, so I will follow this advice.

PS I thought each full watering washed all the salts out of coco, and that was kinda the point of it? If that's true, would I be better feed-water-feed-water?

when I go straight water I water in excess and shop vac the run off just so the leached nutes/salts don't have a chance to absorb back into the plant of course just using a flood tray for run off would work also.

Alexander Supertramp said:

Ummm...so called bloom nutes are only good at draining your wallet. Not growing big buds. They far to often cause much more harm than good from being abused. A 3-1-2 ration with balanced micros and trace elements is all cannabis, along with most container grown annuals, need from start to finish.

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That is true to many people and I even share that idea with newbies when I say try DynaGro start to finish. The last time I gave that advise I did include the option of bloom nutrition at 4 weeks....

Yes you are QUITE correct on the "abuse" of bloom enhancers. Simply look at all "leaves yellowing at weeks 2or3 of flower" questions right here at RIU! That used to be UB's biggest bitch.....stop the abuse of P&K in flower.
Many people need to know that most of your Nutrient companies try to run the formulations and feed charts "hot"....Right about the brink of to much because that's what the "public" demands..."I want the best, biggest and strongest buds I can grow". Sadly you all "read" that higher P&K is "needed" to do this. So you go out and shop for nutrients with that in mind....You buy the ones that have that.....Not many nutrient companies want to loose sales because they sell what REALLY should be the ratio's and simply make huge statements and promise the world. Then many feel that even more will help, and that's where the real trouble begins.

You don't "need" to push so hard! A LITTLE can go a long way....The formula below is quite aggressive!

I find that the prudent use of a slight rise in P&K used once at the flip helps the set. I also bump the N up by 1-0-0
Sometimes I like to bump that again at 4 weeks by like 0-7-5 (every other watering) and at week 6 spike once with 0-9-19, dropping that extra 1-0-0 of N.

Not done with every strain and this is after years of trial and error with synthetic's and synthetic's used with AACT tea's once or twice a week.. Some yellowing in LATE flower does happen.

In the bulk of my grows (organic), I do do some top dressing with high P&K guano's in bloom near the end of the stretch.
I also do some spiking "like" The Rev. does.