Slow growing in Canna Coco. Newbie here! When should I switch to 12/12? LOTS OF PICS

Hi all. I'm so glad I found this forum and this thread. I just wish that I would have found it sooner. I posted this same comment in another thread. I just figured I'd get more exposure here. I hope that's okay. My apologies if not. Just let me know and I'll delete one of them.

• I'm currently growing 12 granddaddy purples
• Vegging under a single 400W MH
• I'm using Canna Coco in 3 gallon pots
• Canna A + B
• Cannazym
• Rhizotonic

I was using Canna's feeding schedule but started having problems. This is my very first time growing, so I've been using the advice of a friend of mine. I've been having problems and now realize that my friend has no idea what he's talking about, hence my gratitude for this forum. He's been telling me that I shouldn't have any runoff; "Canna only tells you to have runoff because they want to sell you more product". He's also been telling me that I should only water when the coco is really dry, like the top two inches are bone dry.


Anyway, I started to notice that my leaves were starting to twist. I was getting some necrotic spots and leaves were starting to look like mutants . It looked like toxic salt buildup according to pictures I've seen online so I flushed and have will be watering every 2 days with runoff. I've also lowered my nutes to about 25% of the recommended and will build up from there. This was 2 days ago and they already look better.

Since I'm new to all this, I have no idea how large they are supposed to be at this point. I thought that coco growth is supposed to be fast and they have been growing pretty slow. I just read some threads about Granddaddy purp and now I believe it's because of the strain.

I have a few questions that hopefully you guys can help out with:

1. PH - When should I test the PH and what should it be at with Canna products? Hydro store guy says to test PH after I add nutrients but I keep reading posts about testing before you add nutes. Canna recommends between 5.2 and 6.2 PH. I've been using 5.8.
2. How often should I water with 3 gallon pots? I was thinking about setting up a dripper system. What is the best type? 1 emitter, 2 or 3 emitters or soaker tubes?
3. Do I really need to flush or is 20% runoff enough of a flush? Canna doesn't recommend flushing. By the way, I've read in this thread to test PH and EC of your runoff but Canna says that testing your runoff (if running to waste) will give you false information. Any thoughts on that?
4. Granddaddy purp is an indica strain so I know that it's going to be short and bushy. When should I switch to flower? They are only about 6 inches tall right now but they are about 12 - 15 inches wide. They are not growing in height very fast but they are growing quickly in width.

Here are some photos of my progress.


Cuttings. Picture taken 6/23 (my first attempt 100% rooted in 8 days!)

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Pregrowing for about a week in 3.5 inch pots to grow rootball. Picture taken 7/6

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Transplanted in 3 gallon pots. Pictures taken 7/7

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Looking better after flush. Picture taken 7/22

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Here is the difference the flush made:

1 day before flush (taken 7/18)



3 days after flush (7/22)



So how do they look to all you pros out there?

Anyone? Surely someone can help me out here? I want to do a SOG but I don't know if it's possible with Granddaddy purp. Are they too short to do a sea of green? Should I switch to bloom now or wait a little longer? They took root on 7/1.

i believe your over watering your plants. coco grows better with little to no runoff. moisten the coco, but dont saturate the coco and you will see explosive results!

ill tell you this, the advice your friend gave you was sound advice, FOR SOMEONE ELSE you can water once or twice a day in coco, its basically hydro, what your doing now is good, you can feed a lesser amount of nutrients and water once day if you like, and yes grand daddy and purple erkle are slow as can be at growing

krunchbubble said:

i believe your over watering your plants. coco grows better with little to no runoff. moisten the coco, but dont saturate the coco and you will see explosive results!

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listen to this guy too, you dont want it soaking wet, you just want to repeatedly keep it moist

krunchbubble said:

i believe your over watering your plants. coco grows better with little to no runoff. moisten the coco, but dont saturate the coco and you will see explosive results!

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Strange, then, how his situation changed for the better once he began not letting the coco dry out AND watered 'til run off.
And those flood/drain guys in coco, well, they never make it to see a harvest because they drown their plants...

im growing in 1.5 gallon grow bags of 75percent coco and 25 organic soil. most days i just water about two thirds a cup of water and my plants are very very happy, u can actually here the water running right through them. what ill do once ever 4-5 days is give them about twice that and get a little run off and then the next few days return to one third to two thirds a cup of water daily, my plants are 25 days old and growing like hydro weed...your plants look like their fed very well with a nice green color...ive heard that coco watered lightly but frequently actually gives the best results and it seems so in my case. just my two cents, im a newbie to coco as well-

Let the coco dry out just a little till the roots fill up some of the pot...then water daily with run off.
Small plants in large pots is the problem!
If you use smaller pots first and then transplant to larger pots the growth will be much more explosive.

Good Luck

Wow. I didn't know there was such debate on this!

So yes, my plants are doing much better now that I flushed and am watering/feeding with runoff. Everything that I've read says that not watering/feeding with runoff will build up salts and then you'll have problems. I think that there is a balance to keeping the coco at the right moisture but from what I've read and seen, it's very difficult to overwater coco. Letting it get too dry on the otherhand will cause lots of problems with salt build up, etc. and can kill off roots which can take a long time to regrow. I'm only speaking from what I've read and heard and the little tiny experience that I've already had...I mean think about it, I had to flush each of my 3 gallon pots with 9 gallons of PH'd water. 12 pot x 9 gallons. That's 108 gallons of water that I ran through total. I had to do it fairly slowly to prevent gurgling. The plants didn't drown. They are actually doing much better. That's gotta show for something right.

Dont know if any of you have visited the Canna website but I'm going to cut and paste what they say about watering/feeding.

"CANNA’s Coco is made up of thousands of capillary micro-sponges that retain almost 1000 % of their own weight in water. Therefore Coco retains an enormous buffer of water and nutrients. It is recommended that the grower keep the medium a bit dry rather than soaking wet. Wet circumstances form an ideal basis for fungal diseases like Pythium. A drier substrate passes more air through to the roots stimulating them to absorb water and nutrients more actively. This results in a faster growth and higher yields.

Another important instrument is timing. Once the Coco has become too wet, reduce or pause watering until the Coco has dried out and then start normal watering again. Check the moisture content of the Coco by hand or by determining its weight by lifting the pot or slab. A rule of thumb for watering fully-grown plants is 4 to 6 litres per m2 a day. By decreasing the dripping frequency and by increasing the amount of nutrients per watering, the best use is made of available water and nutrients. This will also improve drainage. The frequency of watering depends on the evaporation and the water supply in the Coco. A common rule is that one daily watering is sufficient during the first few weeks under normal circumstances; then increase up to 2 times a day; 2 hours after the lamps have been turned on and 2 hours before they are switched off again.

Please keep in mind, smaller root volumes per plant (small pots or many plants per slab) will make Coco dry out quickly. Therefore it is critical to water these plants more often."

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Oh and by the way, does any have an answer to when I should start my bloom cycle? That really is the answer that I'm looking for. Is it too soon now? It's been a little over 3 weeks from root and they are about 6 inches tall.

Thanks guys!

start your budding cycle when you feel your plants are thriving in veg and the size u want, in your case make sure thier back to the level of health u want them before u make the light schedule switch..

it sounds like u really put alot water through your girls, over a hundred gallons u said, thats really wastefull when u think about it, with coco get used to finding the moisture level your plants like, id say water when u water and flush when u flush, once a week a decent flush should be enough to remove salts, i think its totally ridiculous to waste that much water growing anything as well as a waste of effort-

i luv coco, a bag of 15 dollar botanicare coco,one bottle of nutes(floranova) and brita water filter and my plants are thriving, could it get any easier or cheaper?-

I'd lst the plants and wait another 2-3 weeks, then flower.

krunchbubble said:

i believe your over watering your plants. coco grows better with little to no runoff. moisten the coco, but dont saturate the coco and you will see explosive results!

Click to expand...

really! so thats why I had very slow poor growth with my last coco garden.
well Ill have to rember this cuz I just statred some new seed in some coco.

WELL I AM NO EXPERT ONLY only coco'ed once but either flower in a week or so with that many and get bigger pots!!!
http://www.icmag.com/ic/showthread.php?t=115156

As somebody mentioned about 'overwatering' coco... I've read a lot of folks give the blanket statement of "keep it moist you can't overwater coco' as well as the feedback on this thread that says you're overwatering it...It's a good discussion to have...

My experience puts me around where BBQ's post was... I find cuttings without strong root systems did better drying out slightly, making the roots 'look' for moisture like I was told to do in soil when I grew in that....after the roots/plant gets to that point where it's well established around the pot, growth is a little quicker and the plants/roots can take more in and deal with more consistently moist medium....

I adjust the frequency of feedings based on this........Some strong vigorous plants need watering 2-3 times a day by the end of flowering (and cannot be overwatered) to keep the coco moist and some maybe once a day if that much,.......

but cuttings, or just after a transplant, I find the plants are happier to have their roots have to search through that new moist coco a little as it dries out between feedings...

This could also be dependant on the coco you use....I don't remember having to think about this when I was using atami bcuzz coco but now I'm using these compressed bales and have adjusted accordingly...Maybe the bales hold more water (less o2) then atami? Canna is known for having good coco but I have no personal experience with it...

As was mentioned above GDP is known for slow veg also.....

Just my experience.....