Feeding.

[Creed]

Afternoon guys. I'm after a little advice if anyone can give it. I'm coming to the end of the 5th week of flower. I noticed a week or so ago that a few leaves on a few branches were becoming a little pale. After another feed it became worse and then another feed it became worse again. What I've noticed is that it's only certain branches. The plant is scrogged and all the effected parts are within the centre of the scrog. I've recently lifted my light as during stretch the plant grew to within 8 inches. Now it is sitting at around about 12 inches. I initially thought it was maybe a little bleaching from the light being so close but then since it got worse after a couple of feeds, I've now ruled that out.

The plant is being fed every 48hours using biobizz 3ml fish and 6ml bloom per 4 liters water. The last few feeds I have mixed all my nutrients in a jug with 2 liters of water and fed. Then 2 liters of plain water after so 4 liters total. Since doing this is when I've noticed the yellowing. Is it possible that feeding 2 liters of plain water after 2 liters of nutrient mix that I have effectively flushed my nutrients to the bottom of the pot and the yellowing is a symptom of the roots all not absorbing any nutrition?

I hope this makes sense. Any advice is greatly appreciated.

[BilgePump]

Just now, Creed said:

have effectively flushed my nutrients

Yep.

 

[Clubs]

It sounds like you've got a hot spot in the centre so you were correct to raise the light. Even after raising the light, those leaves will continue to yellow and degrade.12 inches might still be a bit too close, depending on the power/configuration of your fixture. 

[latigid aikon]

16 minutes ago, Creed said:

biobizz 3ml fish and 6ml bloom per 4 liters water.

That's very weak, only 0.75ml/L fish and 1.5ml/L bloom.

16 minutes ago, Creed said:

Then 2 liters of plain water after so 4 liters total.

And that effectively halves it again, so 0.375ml/L fish and 0.75ml/L bloom. Actually it doesn't, if it was 4 litres fertigation then 2 litres irrigation it's a bit less diluted than half but that's as much maths as I can be bothered with

Edited December 21, 2023 by latigid aikon
wrong maths

[latigid aikon]

Just now, Clubs said:

It sounds like you've got a hot spot in the centre

Yes but it sounds like the plant could handle that light if it had enough feed, more light = more nutes.

[Creed]

Just now, latigid aikon said:

That's very weak, only 0.75ml/L fish and 1.5ml/L bloom.

And that effectively halves it again, so 0.375ml/L fish and 0.75ml/L bloom. Actually it doesn't, if it was 4 litres fertigation then 2 litres irrigation it's a bit less diluted than half but that's as much maths as I can be bothered with

My last indoor grow (and first grow) was a few years back and I heavily overfed. I wasn't prepared to make the same mistake again. I've since been strictly guerilla, which is so much easier. This year my plot was discovered due to deforestation so had to set the old tent up. My light is mars hydro TS1000 I believe,150w?

So what would you recommend I try now? Maybe lift the light to 15 inches, up the bloom nutes to maybe 8ml, so 2ml per liter and what about the fish mix? Since am so close to harvest is it even worth upping the nitrogen?

If nothing else I plan on running this same strain again after this so I have learnt from my mistakes. 

Thanks for all replies guys, much gratitude.

[latigid aikon]

You're more likely to burn them with the fish than the bloom by a wide margin and, as you say, they don't need much nitrogen at this stage so increase the bloom a decent amount but I'd still increase the fish to maybe 1ml/L. The fish is available to the plant much faster than the bloom so you'll see results sooner if you increase it even a little bit.

 

Some of us are convinced that Biobizz is weaker now than it used to be, there is also a suggestion that the feed in their trial packs is stronger than the larger bottles...

 

FWIW the biobizz guide suggests 2 or 3 ml/L bloom at this stage and also a similar amount of fish if you are using light mix compost.

[Creed]

Just now, latigid aikon said:

You're more likely to burn them with the fish than the bloom by a wide margin and, as you say, they don't need much nitrogen at this stage so increase the bloom a decent amount but I'd still increase the fish to maybe 1ml/L. The fish is available to the plant much faster than the bloom so you'll see results sooner if you increase it even a little bit.

 

Some of us are convinced that Biobizz is weaker now than it used to be, there is also a suggestion that the feed in their trial packs is stronger than the larger bottles...

 

FWIW the biobizz guide suggests 2 or 3 ml/L bloom at this stage and also a similar amount of fish if you are using light mix compost.

I was previously feeding 4ml fish but began to lower the amounts since I am getting close to the end. Then this issue began so I remained at the lower amount of 3ml until I got some advice. I thought that higher nitrogen would inhibit flower development so my plan was to decrease the fish by 0.5ml every other feed until i reached 2ml total so 0.5ml/liter. I'm guessing due to my fear of overfeeding I have probably gone most of veg actually underfeeding?!  The plant looks healthy still. Leaves perky with no crispy edges or rust spots. The flowers are developing very nicely also. To be honest I haven't followed the biobizz chart. I have gauged it by looks.

I'm due a feed tonight so I will up the nutrients and see how that serves me.

Thanks again for advice.

[stayup4ever]

personally i'd up the feed. that does seem very weak..i'd go for 4 ml fish and 12-16 ml of bloom in 4 litres of water and see how that goes

[latigid aikon]

17 minutes ago, Creed said:

The plant looks healthy still.

Any chance of some photos?

[Creed]

Just now, latigid aikon said:

Any chance of some photos?

I will see what I can do tonight. Lights aren't due to come on until 6pm. Gives me some time to try and work out how to upload. I had my suspicions it was underfeeding but didn't want to gamble with it, without some experienced advice. I think anyone looking at it would most likely say she is hungry but as a new grower it wasn't worth trying to rectify and potentially create a more serious problem.

[Creed]

8 minutes ago, stayup4ever said:

personally i'd up the feed. that does seem very weak..i'd go for 4 ml fish and 12-16 ml of bloom in 4 litres of water and see how that goes

As much as 12-16ml? Will such a large increase be safe? I don't want to cause any toxicity. I'm watering every 48 hours so how about raising to 10ml today then further 2ml increases during the next few feeds until I reach 16ml?

[latigid aikon]

2 minutes ago, Creed said:

As much as 12-16ml? Will such a large increase be safe?

That's 3-4ml/L which will be fine if it's bloom, it's the fish you need to be careful with.

[Creed]

Just now, latigid aikon said:

That's 3-4ml/L which will be fine if it's bloom, it's the fish you need to be careful with.

I appreciate this, thank you. I will attempt to upload some pictures later for confirmation. I will possibly start with 12ml tonight and then 16ml next feed. Hopefully I will see a noticeable increase in flower size, although they are making steady progress but any increase in size/weight then I'm happy.

[latigid aikon]

Just now, Creed said:

start with 12ml tonight and then 16ml next feed.

Sounds like a good plan, keep a close eye on them to see how they react. You're not going to see pale leaves returning to green BTW, the best case is them not getting any worse.