HEY EVERYONE, I have a plant that's been a slow grower from the start. Planted in happy frog mixed with perlite and dolomite lime. The pH ended up being really low (4.7ish) so last week I added hydrated lime and the last runoff reading was done about two days ago. It was 5.7 so the extra lime helped a bit but it's still really low. I checked on it again today and it has some brown spots mostly on the upper growth. I'll attach some photos but I was thinking it was a Phosphorus deficiency! I'm feeding with foxfarm nutes. Also, it's worth noting that the plant smells pretty strong, but the flowers are still REALLY small and haven't been growing much. Any advice to fix these issues?
Phosphorus Deficiency?! NEED HELP!
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Hi Growgirl, at that pH you're prolly looking at N, P, K, Ca and Mg and maybe others like sulpur and Zinc deficiencies, ...their availability is severely impaired if soil is acidic. I would flush real hard with tap water (24 hr aereated to get rid of chlorine), or ROS water, use a volume equal to 3 times your container and after your soil pH is stabilized in 6.5-7.3 add the nutes.
Is that an Autoflower? What week?
Is that an Autoflower? What week?
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:smoking: Hi GG'-- ...I recall you were here before,.. same plant/issue? If so, I probably mentioned FuxFarms soils being really iffy these days,.. undercooked, overly acidic! ...wise that you added some dolomite, but it's either not enough, spent, or releasing too slowly due to larger granule size-? (did you use a powder-like grade, or sand,...?)-- Of all the limes, it's the slowest acting because of it's slightly different chemical make up,...courser grade stuff is very slow acting, usually not in time to fix anything, especially speedy auto's! Ag lime is a better choice in most cases.... I love your gutsy move to try hydrated lime! I've had to use it last season as well, and it's great if you're careful with it-- looks like you were- 
....Also, your feeds are rather acidic, so there's a source of acid input as well,... do you pH adjust your nute's before feeding? some things to consider: your ph meter, is it clean and calibrated often? How are you testing the soil pH? If it's the run-off method, consider the readings as no better than a rough estimate; as a method, it's prone to measurement error,... check out the sticky article here, near the top of the content page; it has an improved methodology at least,... best choice is with an soil pH probe, direct measurement... Accurate 8 makes a good one for the $!
So, the fix... Bush' made a good call with the flushing; what's you water source, and it's natural pH? ..need to see how about hard (mineral content) it is- (you wouldn't happen to have an EC or TDS meter?.. that will answer that ? right away!); overly hard water is not a good choice either, and if really soft, you may need to add some Ca-Mg supp' to it...A very helpful product is a rinsing/flushing agent (Boomerang, Clearex, etc.) which are surfactants that help knock loose the particle bound ions-- but absolutely necessary,... your symptoms are looking like P defc., which fits with the low pH..much below 6.0, and it's starts to lock out fast! Ditto for S, which the pale color hints at as well,... when flushing, make sure to do it fast, 20min. about, or the water logging of the soil will mess with the O2 uptake,... on the last pour through, add 1/4 str. nutes+ Ca-Mg, or better epsoms salts (MgSO4) which will get some S in there fast (1tsp/qt),.... get me the info I need, and we'll dial things in from there, okay?
....Also, your feeds are rather acidic, so there's a source of acid input as well,... do you pH adjust your nute's before feeding? some things to consider: your ph meter, is it clean and calibrated often? How are you testing the soil pH? If it's the run-off method, consider the readings as no better than a rough estimate; as a method, it's prone to measurement error,... check out the sticky article here, near the top of the content page; it has an improved methodology at least,... best choice is with an soil pH probe, direct measurement... Accurate 8 makes a good one for the $! So, the fix... Bush' made a good call with the flushing; what's you water source, and it's natural pH? ..need to see how about hard (mineral content) it is- (you wouldn't happen to have an EC or TDS meter?.. that will answer that ? right away!); overly hard water is not a good choice either, and if really soft, you may need to add some Ca-Mg supp' to it...A very helpful product is a rinsing/flushing agent (Boomerang, Clearex, etc.) which are surfactants that help knock loose the particle bound ions-- but absolutely necessary,... your symptoms are looking like P defc., which fits with the low pH..much below 6.0, and it's starts to lock out fast! Ditto for S, which the pale color hints at as well,... when flushing, make sure to do it fast, 20min. about, or the water logging of the soil will mess with the O2 uptake,... on the last pour through, add 1/4 str. nutes+ Ca-Mg, or better epsoms salts (MgSO4) which will get some S in there fast (1tsp/qt),.... get me the info I need, and we'll dial things in from there, okay?
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