urgent help ph problem or nutrient deficiency?

Hi all,

Really need some help as I've had a couple of ruined harvests and it looks like this is going the same way

I'm growing in soil, all mix with a bottom layer of super soil.

DNA genetics Silver LA

Bio biz nutrients bloom, grow and top max

Temps are all good under 250 hps

Run off was a little high when i checked it but can't trust my PH pen too much so used the strips to make sure. Run off is probably around 7.5 to 8.

I have used water only at around 6.0 to see if this would help.

Run off when I normally flush is very dark brown at first but run off from this is very light coloured, could this be a sign of low ppm (waiting for my new TDS metre)

All was good up until week 3 or 4 of flower then the lower to middle leaves started seeing brown blotches which has crept up to the top.

Could this be PH problems or deficiency?

Any help please

At this late in the game, I would just let the plant drain its resources. Buds look almost ripe and leaves can spare some more nutrients for a few weeks, the plant wont need them long.

You could add a handful of gypsum but calcium is a slow mover and Im not so sure the plant will do anything but pull it from the plant at this point.

A cup or handful of gypsum half way through the grow on your next run will help.

NaturalFarmer said:

At this late in the game, I would just let the plant drain its resources. Buds look almost ripe and leaves can spare some more nutrients for a few weeks, the plant wont need them long.

You could add a handful of gypsum but calcium is a slow mover and Im not so sure the plant will do anything but pull it from the plant at this point.

A cup or handful of gypsum half way through the grow on your next run will help.

Click to expand...

Thanks, I've toped dressed with lime and a little azomite but not sure this has time to take affect.

It has a little gypsum mixed in globally but I'll definitely top dress earlier next time.

This won't affect the taste and flavor if I don't put any nutrients in from now on? Or will it do more harm then good if I load it up with some bloom nutrients?

Is they're a quick way to lower the ph? Say water with a low ph mix?

Thanks for the advice

You could top dress with some peat but I think your pH is probably fine. I think your mix may have lacked some N and available calcium but overall looks like you got fairly good quality.

NaturalFarmer said:

You could top dress with some peat but I think your pH is probably fine. I think your mix may have lacked some N and available calcium but overall looks like you got fairly good quality.

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Thanks, in was a little cautious on the lime when I mixed the soil so that would make sense.

I'll probably give it one more feed and check the run off once more plus add a little more gypsum, Lime and azomite in a vain hope it'll make a difference in the final 2 weeks.

Can I add all 3 in small doses at the same time as a top dress? Heard somewhere you shouldn't add lime and rock dust at the same time, not sure how true this is as I haven't heard before then.

Cheers

Alex

NaturalFarmer said:

At this late in the game, I would just let the plant drain its resources. Buds look almost ripe and leaves can spare some more nutrients for a few weeks, the plant wont need them long.


You could add a handful of gypsum but calcium is a slow mover and Im not so sure the plant will do anything but pull it from the plant at this point.

A cup or handful of gypsum half way through the grow on your next run will help.

Click to expand...

Just a quick one, the lime and azomite are very fine powders but the gypsum I have is like granules, would it be best to pulverise it before to dress or just leave as it is?

I would leave them prilled to reduce dust, I dont think it will break down any faster by crushing it. Just scratch them into your soil and water. They will cake if you don't scratch it in.

NaturalFarmer said:

I would leave them prilled to reduce dust, I dont think it will break down any faster by crushing it. Just scratch them into your soil and water. They will cake if you don't scratch it in.

Click to expand...

OK my TDS metre arrived.....very low ppm as expected. Around 400 ppm last feed. My tap water is 350 and after brita filta it's 200ppm.

Could it have been low nutrients (N and P) all along?