Deficiency after flush?

[WisdomKarp]

Okay, well, I have a new problem.
Here's the background, I basically just gave my plant a flush to sort some nute burn.
https://www.autoflower.org/f34/sudden-withering-leaves-help-me-out-=-13563.html

That's the thread. Details about my setup haven't changed but the yellowing of the new growth that I meantime has gotten worse. Here's some pics:
View attachment 146963View attachment 146964View attachment 146965View attachment 146966View attachment 146967View attachment 146968View attachment 146963
I should also point out that due to my phone being a bit rubbish, it's not doing the colours quite right and in real life, the leaves are a lot more yellow than they look here.

Basically, I'm thinking it's a deficiency caused by me maybe flushing all the nutes out, or something. Maybe nitrogen or magnesium perhaps? I'm not sure, hence why I'm needing opinions from experts like yourselves ^^.

So yeah...help? ^^;

 

[Muddy]

Flushing does leach all the nutrients out of the soil so they do need to be replaced. If I'm flushing, say 6 gallons through a pot, I'll do the first 5 with plain, pHed water, then the last gallon with some mild nutes, again, pH adjusted. Give them a light feeding and they should start to improve.

 

[WisdomKarp]

Alright, thanks for the reply. Just wondering, should I feed immediately or should I start a nutrient tea going and feed in a day or two?
Also, which nutes should I focus on, or should I just feed a bit of everything, I was thinking some nutrient tea with blood meal, seaweed kelp, epsom salts, earthworm castings and molasses, maybe?(along with a pinch of soil), or should I stick to just blood meal, molasses and a pinch of soil?

 

[Muddy]

Most of the things you've listed, like blood and kelp meal, both of which supply N, are slow acting and you need to hit them pretty quick. I would suggest you feed them right away with a complete veg nute, something like Fox Farms Grow Big or something comparable. I'm afraid if you wait on the blood and kelp meal to become available to the plant the damage will be a lot worse. A foliar feed of a mild veg solution would also be very helpful.

 

[WisdomKarp]

Ahh, okay, my bad, I was under the impression that they'd act faster if used in a nutrient tea.
I have a 6-5-9 with magnesium nute solution designed for tomatoes, should that do? ( I heard tomato nutes were good for cannabis somewhere).

Thanks again for the help =).

 

[Muddy]

Apparently the water solubility of both blood and kelp meal varies depending on the particular brand. The Miracle Grow blood meal I've used in the past was very slow acting, often taking several weeks to become effective. Judging from the overall light green color of your plants I think they need more N now than anything else. I suspect the curling of the leaf edges and their brown color was a result of the lock out. Since they are still vegging I would be more inclined to use something higher in N. like an 8-4-4 or something similar. The tomato nutrients you listed would be more effective as a flowering nute.

 

[WisdomKarp]

Ah, I see. The kelp is actually liquidised seaweed, as for the bloodmeal, I bought it from an online fertiliser retailer that I think is more of an independent farm selling byproducts than a large brand. I did so since they sold 2kg of the stuff for a couple of £ (I'm in the UK), but it's ground up into pretty fine powder.
And ah, fair enough, I'll go buy an 8-4-4 fert tomorrow(It's 10:25pm here, so all the shops are shut), and hopefully that should fix things, I'll keep this thread updated on how it goes =).

 

[WisdomKarp]

Another question though. I've just watered it with some of the high N fert and I've foliar fed with the same solution, I'm just wondering, how long does recovery take? I'm thinking about a week, but I want to ask to make sure.