12-day old seedlings. I went up to 1.5EC a few days ago using only Canna nutes, (Canna A + B, Rhizotonic and Cannazyme), at the recommended dosages. (pH 5.9 - 6.0) No problems while under the CFLs. Today I watered with the same mix, allowed things to settle for 30 min, then put the plants under the 400W HPS at 18" and both had chlorosis between the veins within an hour. (Thought I'd splashed nutes on the first plant but spilled none on the second and it shows the same symptoms, they just took a little longer to show.) The question - is it usual to drop the nute concentration for a short time when going from CFL veg to HPS flowering lighting? Everything was going perfectly until I tried putting them under the HPS. They are very young at 12 days old. Lucky I noticed it quickly and moved them from under the HPS. If I see any further symptoms, ie Drooping or more burns, I'll flush them but I'll try to avoid it. Any advice appreciated. A pic taken about an hour afterwards:-
Isnt 1.6 ec a little much for 12 days old ? Im on 14 days and still on 0.8 ec . Will bring up to full strength slowly for the 25th day.
Im on a similar setup, u can check my grow here.. http://forum.grasscity.com/indoor-grow-journals/789270-grow-journal-snowryders-afghans.html
I'd say that's probably my problem. As a coco/hydro novice, I've been following the Canna instructions by the letter. Their recommended feeding schedule is attached. N.B. This feed-rate is based on an original water EC of 0.2. The EC+ values on the chart are for distilled water. Edit: Just checked out your grow. We do have similar setups. Already looks like I should have gone with half-strength nutes. The Canna schedule is fine under the weaker CFL light. Lucky I noticed the damage early and moved them back out from under the HPS. I only intend pushing one into flowering. The other one was in there for the stronger light and was going back under the CFLs at the end of the 12 hours when the HPS turned off. They're both cooling their heels under the CFLs again for now.
matlear, as an afterthought, what's the highest you intend to take the EC during your grow? (As you see, the Canna chart goes up to 2.2.)
I just drew up a new, milder feeding schedule, starting with an EC of 0.7 and peaking at 1.8, (attached). Hopefully this'll do the trick:-
Well I used Canna Coco nutes for my first two grows and I use the week 1 nutrient mix for at least 2 weeks before I switch to the veg mix. I use the recommended mix for my PPM. I've always gotten a spots like that on some of the early leaves when I move from seedling to full veg. So far it's only on a few leaves and it stops quickly once the plants kick into fast growth mode. One of the reasons I started using the week 1 mix for 2 weeks, (3 weeks if you cloning into coco) is that I saw less of the spotting. I can tell you that I panicked during my first grow and starting messing with the Canna recommended balanced. In short, don't... here are a few tips from my first two grows. I clone right into a Solo cup of coco saturated with week 1 mix. Cover it with a sandwich bag and put it on a shaded shelf in my veg tent, no direct light. Water clone every day and I also spray inside the bags with a mister as my veg tent humidity can get kind of low. After first 7 days, I take the bags off and move them to indirect light. After 14 days I move them into fairly direct light but they are 18 to 24 inches from my 250W MH. After 21 days I switch them to standard veg nutrient mix. After 28 days they are normally ready for replanting into a 3 gallon pot (my grow tent is 7 feet tall with about 6 feet of clearance under the light). Once they get to the proper height move them to the flowering tent but keep them on the standard veg mix. I move mine when they are 18 inches tall to get plants that are about 3.5 to 4 feet high. Keep feeding them the standard veg mix until you start to see pistils coming out from your nodes. Once you see pistils then feed it the part 1 flowering mix. Chart says 1 to 2 weeks but I only do it for 1 week as they tend to get N burned if you go 2 weeks at the elevated A&B levels. After you feed part 1 flowering mix for 7 days then switch to the part 2 PK boost mix for a week. After 7 days of PK mix then settle in to the part 3 flowering mix. Keep feeding the part 3 flowering mix until your buds get to roughly their full side. Normally you will be feeding this mix for about 3 to 4 weeks. Once your buds are filled out switch to the final part 4 flowering mix. Feed the part 4 flowering mix until you are 7 to 10 days from harvest and then switch to plain water. As far as the Bloom I start out at the low end with part 1 and end up at the high end when I hit part 4. Increasing it during every switch. Don't worry too much about how the leaves look, just stick to the system and it will work for you. I gotta say though, I recently dumped the Canna Coco for H3ad's Modified Lucas Formula for coco (GH Flora Micro 6ml per gallon and GH Flora Bloom 9ml per gallon) and it's way cheaper, way easier and there is only one two different mixes. Additionally it's working well and my plants look great. Good luck man!
Good one, thanks for the Canna nutes specific feedback. I'll keep a copy of your last post for reference. Not many people use the Canna line due to cost, but as a coco newbie, in my opinion their grow guide calculator was better than I could do myself. I noticed their EC values were a bit high, but wanted to test their schedule first. Like you, after the first couple of grows I'll start trying cheaper alternatives, once I have a benchmark to compare to. I was shocked when the burns appeared so quickly after feeding and expected worse symptoms to follow, but about 24 hours later there are still only a couple of burns and in all other respects the plants are raging. I might put aside my new schedule for now, drop back to 1.3EC for a bit longer starting next feed tomorrow and at the same time put one back under the bright light and see how it goes. As you suggest, I'll go back to their recommended feeding in about a week. Thanks again for a good reply.