TabbyDee
Well-Known Member
All my lower fan leaves have turned yellow and died. Almost half way up the tree. I give it bloom nutes at 0-5-4 and cal-mag. I know yellowing is normal during flowering but it’s only the fan leaves. Any thought?
Lower fan leaves turning yellow and dying?
- Thread starter TabbyDee
- Start date
Emilya Green
Well-Known Member
It is a lot easier to diagnose when we can see some of the yellow, because the plant looks pretty good from this picture. From your description and looking at the picture, I think it is a good possibility that you are rootbound in that small container that is now so top-heavy you have to prop it up with cinder blocks. Triple the size of your container and I bet things will look a lot better, and as a bonus, it will be able to stand up to a wind.
In addition, lower leaves turning yellow and falling off is a sure sign of nitrogen deficiency. Your bloom fertilizer has no N and she has a long way to go.
Beautiful plant in the photo!
Beautiful plant in the photo!
- Thread starter
- #4
TabbyDee
Well-Known Member
I have a miracle grow bloom fertilizer at 15-30-15. I know it’s not set up for weed but,
I used MG 20-20-20 during veg with blackstrap molasses and just started giving the 0-5-4 with cal-mag. Do you think I should use the 15-30-15 with cal-mag? And when do I switch to the 0-5-4?
I give her molasses once every week regardless. And regarding the pot… I thought it would be big enough, but two weeks before flowering she tripled in size on me and now isn’t it too late to repot? I would cut the bottom of the pot off and stick it in the ground, but then I can’t move her to protect her from bad weather. Lesson definitely learned. Next year I’m going to pinch so they grow wide and not tall.. thanks in advance
And here’s a pic of the yellowing. From those two leaves down there are no fan leaves left.
Yeah, transplanting her now would be challenging. You can keep her in that pot, but you’re going to have to baby her with daily fertigation since that soil is done and she’s rootbound.
Contrary to what you have probably heard, cannabis plants need nitrogen even in flower. However, neither of the fertilizers you mentioned are appropriate. MG uses too much urea for nitrogen and the P is too high. Can you get a complete water-soluble fertilizer - something like Jacks 12-4-16 or MegaCrop?
Contrary to what you have probably heard, cannabis plants need nitrogen even in flower. However, neither of the fertilizers you mentioned are appropriate. MG uses too much urea for nitrogen and the P is too high. Can you get a complete water-soluble fertilizer - something like Jacks 12-4-16 or MegaCrop?
- Thread starter
- #6
TabbyDee
Well-Known Member
So I should feed her with every watering?
I’m only doing it once a week right now.
Emilya Green
Well-Known Member
That would probably result in overfeeding. Soil is designed for f/w/f/w
Once the nutrient load in the soil has been depleted, it’s no longer really a “soil”, and the plant is dependent on the application of nutrients from the grower - either with dry, granular fertilizer as a periodic top dressing, or by more frequent fertigation with a fertilizer solution. If fertigating, and you just water in-between feedings, the nutrient load in the substrate may be a lower concentration than the plant needs.
- Thread starter
- #9
TabbyDee
Well-Known Member
I found something here in Canada that is 10-5-15 Do you think that is good? Thanks
The NPK sounds good. Is it dry or liquid? Could you post the complete analysis off the label?
- Thread starter
- #11
TabbyDee
Well-Known Member
I didn’t get it yet and this is all I could find on it. I know it’s not made for weed but I used 20-20-20 throughout veg and it was good. What do you think?
The only thing I don’t like is that it’s shake n feed not liquid.
It’s a nice try. On the surface, it looks like it has the right amount of everything. But, as usual, MG/Scott’s/Monsanto use cheap urea as the main nitrogen source. This is not what you need. You need nitrate nitrogen, which is immediately available.
This is a solid choice - with three types for different grows.
What stores do you have in your area? There has to be other fertilizers other than Miracle Grow. It's not about MG being owned by Monstanto. General Hydroponics and Bonticare are owned by Monsanto too. It's just that they use cheap ingredients.
- Thread starter
- #15
TabbyDee
Well-Known Member
I found a store called Central Grow City.
But I think I’m going to harvest in a little over 30 days. So do you think I should just leave it alone? I read that yellowing close to harvest is normal.
Hiya - it is normal, but most folk trail off feeding over the last few weeks rather then just suddenly stop altogether
I only stop feeding about a week before the chop, then just water
- Thread starter
- #17
TabbyDee
Well-Known Member
Thanks : }
I didn’t get it yet and this is all I could find on it. I know it’s not made for weed but I used 20-20-20 throughout veg and it was good. What do you think?
The only thing I don’t like is that it’s shake n feed not liquid.
I wouldn't use that stuff.
Over kill in a large soil container.
Miracle grow = Scott's roundup
Same company.
Yellowing down low is normal for most cultivars.
Scenescence is the process. The plant is translocating stored minerals and elements to flowers that are forming. Dont pull them off let them fall of naturally.
That process is called leaf absission and is normal.
Unless you know for certain your soil is deficient you dont need all that fertilizer and certainly you dont need any cal/mag.
- Thread starter
- #19
TabbyDee
Well-Known Member
Doesn’t cal-mag help the plant absorb the nutes? And the big fan leaves that come off the main stalk have turned yellow and died half way up the tree all the other leaves on the branches are green even at the bottom, that’s what I’m concerned with.
Not really - it’s to address deficiencies. CalMag should really only be used to get the Ca ppm up to about half the K ppm and the Mg ppm up to about half the Ca ppm. Do you have access to a water quality report? You might be getting enough (or more than enough in some areas) from your water. If you have very hard water, you probably will be better off using RO.
