Issue with late flowering using miracle gro

This is..... hypothetical....as a disclaimer.

Suppose for 2 years, I been closet growing using only miracle gro soil from start to finish, no transplanting, no flushing.

First month, perfect in every single way, I add no nutes, just water every other day in small amounts, however in a big pot over 5 gallons in size.

Second month, buds start producing nicely, old leaves turn yellow and die off(natural by all counts) and I trim the bottom and at the beginning of the second month, I cut the top of the main stem for multiple (5 or 6) bud sites(dunno a better word). I start using miracle gro nutes with my watering once a week(only water really twice a week) watering total a gallon each time, again twice a week after the soil appears dry.

The problem is....I start to develop these spots on the leaves(top and middle) that are black and spotty(like necrosis), including the leaves turning yellow. I am having a issue deciding on either if it is a manganese deficiency or a magnesium deficiency.

This is in late flowering im facing this issue and only in late flower do I have this issue. ~2 weeks or so away from harvest period, I would like to fix this, also for my future grows as well.

I am not changing soil, going to hydro, etc..... I know its a deficiency of some sorts and would like some advice.......hypothetically speaking.

Thank you in advance.

Edit: Soil PH is ~6.5 and from everything I see, thats the zone I need to be in.

Edit 2: After flowering beings, I use miracle gro bloom (1/2 teaspoon) with a gallon of water, basically every other feeding with is once a week until the last week of flowering(right before harvest).

Miracle grow chemical nutrients are poison.

so are you suggesting that I no longer use the miracle gro bloom for added nutes? I have experienced nute burn in the past by using too much, but thats not the case atm.

So I decided to attempt a magnesium fix and use epsom salt. I used 1 tsp in my gallon of water with nothing else. Assuming this is the issue, will the leaves show improvement or just not get any worse? Also, how long would it take for me to witness the results? days, week?

I noticed zero difference using Epsom salt, the leaves started out yellow with rust like spots on the middle and upper leaves, lower leaves were green with no problems, I did follar feed plus 1 teaspoon per gallon of water. Some leaves did curl in both directions, again middle and upper, including yellowing.

Any advice? I do think one issue could be heat which I don't leave the door open all the time. But what else does this sound like? I know it's not nute burn, been there last grow. Thx

Yes to avoid this you should flush with PH'd water every 4-5 feeds to remove excess salts, also use a larger pot next time because it will have less salt build up than a small one and less root system stress.

Once leaves are damaged, they will not improve. New growth should be normal if the deficiency has been corrected.

beginner.legal.growop said:

Miracle grow chemical nutrients are poison.

Click to expand...

all nutrients are chemicals, miracle grow is not poison. if it were poison i would not plant my aging mother's garden with it every spring for 20 years.

most likely OP is suffering a micro nutrient deficiency. try adding a good quality micro nutrient supplement, or a small dose of a different nutrient (african violet or orchid flower nutes) every other fertilization cycle instead of the usual stuff. and see how that goes.

if you are focused on manganese and magnesium, a low dose of epsom salts added to your fertilizer mix (a teaspoon or two per gallon) will add magnesium. manganese deficiency is uncommon unless you use the same soil year after year, which would bring it's own problems unless you add compost in between plantings. adding a tablespoon of common supermarket molasses to your water will add manganese, or you can get a manganese vitamin supplement and grind that up in your water too. .

if miracle grow potting mix and fertilizers are working for you, rock on. miracle grow soil is one thing i hate and would never recommend, but if its working for you, then do it up homey. dont believe the organic hype. real natural farming is best, but synthetic fertilizers work fabulously if you control the dosage, and get everything needed for plant health

Edit: once again buds has an excellent point, it could be salt accretion, flushing might fix it if epsom salts didnt help. when a plant is growing and doing well except for a minor thing i often try molasses. its got so much stuff in it that it often has the key to the problem hidden inside it's dark mysterious sweetness