We are first time growers and struggled a bit with using Flora Series. I hope someone out there can learn from my mistakes and success. And, if anyone out there has more experience, please offer some advice to us. Thank you!
We’re growing clones of Strawberry Cough indoors with Advanced Spectrum Max LED grow light for flowering and compact florescent lights for vegetative growth. We leave the veg light on 24hours a day. We use Fox Farm soil with perlite in large clay pots. We have 3 plants flowering, each put in 12/12 about 25 days apart and 2 plants still in veg (one of those is trellised with HST).
For nutrients, we use General Hydroponics Flora Series, a 3-part system. We’ve had some bumps along the way figuring out how much of each part to add. Of course, our first few recipes were too strong. As a result, we saw deep dark green leaves that had different texture and clawing. With our first flowering recipe, we started getting burnt tips too. We flush and try again. After weakening the flower recipe, we watched dramatic yellowing of fan leaves on the oldest two, but smaller leaves near bud sites remain lush and green. Today, I noticed veinal chlorosis (breakdown/loss of chlorophyll in the veins) on plant #3 which has been flowering for about 2 weeks but was perfectly lush and green till 3 days ago. Here’s what I’ve found…
The recipe on the Flora Series bottle was too strong.
The recipe I found on the internet was MUCH weaker. The plants loved it in the vegetate stage, but once I put them under 12/12 and started them on the weak flowering recipe (provided by the same source), they started yellowing and some brown spots eventually appeared.
This is the weak veg recipe: (per gallon)
1/2 teaspoon of Micro
1/2 teaspoon of Gro
1/4 teaspoon of Bloom
This is the weak bloom recipe: (per gallon)
1/2 teaspoon of Micro
1/4 teaspoon Gro
1/2 teaspoon Bloom
I want to try to increase the nutrients for my flowering plants. And I realized I can’t give all 3 flowering plants the same fertilizer recipe since they’re in different stages of flowering. So, I began down a mathematical rabbit hole of ratios and even attempted algebra equations to analyze recipe options (which didn’t work). I’m talking NPK ratios of course. Internet sources recommend N:K ratio of 1:1 during vegetation and 1:2 during flowering. I’ve read about the 1,2,3, system: 3:1:2 for veg and 1:3:2 for flower, etc. Then, I started running the ratios for the recipes that General Hydroponics supply and what I discovered really helped me understand what’s going on.
Yes, there are ideal NPK ratios for each stage, but the schedule transitions you to those ideal ratios gently. So, the ratio isn’t always exactly that ideal ratio 1:1 or 1:2. But sure enough, Early Growth Week 2 and Mid Bloom Week 9 were close to those ideal ratios.
So, going forward I’m going to think of those ratios as the ideal ratio for the peak of that stage not the end-all-be-all.
Along the way, I learned more about veinal chlorosis, where the vascular system shuts down and stops creating chlorophyll due to a nutrient deficiency of iron, magnesium, and/or nitrogen. Magnesium and sulfur are needed to produce chlorophyll… The plants were basically screaming for a Cal-Mag product.
I was blinded by the burn. The early signs of this deficiency were mistaken for, masked by, and even accelerated by nutrient burn (too much P can lock out Zinc, Iron, and Copper). Once I thought I had added too much, I wasn’t thinking about adding more of anything.
So, we just started feeding them 2 ml per gallon of Sensi Cal Mag Extra with the Flora Series. I wasn’t sure if we needed CalMag when we started. I thought do we really need to buy another bottle of stuff? My dad didn’t use that 30 years ago. Is it really necessary? Yes, for me it was, and I wish I had in the beginning.
I think my nutrients could/should be stronger can’t find any advice on the internet how to increase my recipe safely. So, I’ve devised a plan myself. And the next day I made 2 different batches and tested the PPM of each.
The flower recipe that I had been using:
2.5 ml Micro, 1.23 ml Gro, 2.5 ml Bloom, pH adjusted to 6.3 PPM = 483
Next, I mixed up the new recipe I was considering and tested the PPM:
4ml Micro, 1ml Gro, 5ml Bloom, pH adjusted to 6.3 (without calmag) PPM: 529
I was surprised that the PPM wasn’t that different. I thought, certainly it should be safe to switch to that recipe without harming my plants. But the next day the amount of yellowing leaves on plant #3 went from 4 to 10! What the @%$#?
So I do more research… And I find that I was switching to bloom recipes too quickly. I found this very important advice:
“It is best to switch from veg to bloom about 2-3 weeks into flowering. This may cause a bit more stretch, but your leaves will be healthier and your buds will be larger. on the second week of flower, it is best to flush for 1 week with water, then switch to bloom nutes. you can shorten this to as little as 2-3 days also, or not even flush at all. this way you won’t lose as many valuable fan leaves/lower branch leaves immaturely.”
I was switching my plants fertilizer recipe to bloom as soon as I put them under 12/12 lights. There was no indication on the feeding schedule provided by General Hydroponics for Flora Series that a 2 week delay was recommended. Well, I wont make that mistake again. But I’m still not sure what to do from here since plant 3# has been under 12/12 for 18 days now. Is it too late to go back to veg recipe? I think I’ll increase the Gro to give it extra nitrogen next feeding. But I need to be patient and let them really dry out because over watering can cause yellowing as well. Updates to follow.