Sick plants - in need of diagnosis help

[Slysir 9]

Hey All,

 

This is a first time grow. I have 3 plants in a 60cm x 60cm set up. They are Purple Bud from Sensi Seed. Size of strain is meant to be small (so suitable for the compact area).

 

Since first germination to today it has been 43 Days.

Grown in soil medium, approx 20 litres.

LED 400W

The plants are on a 18/ 8 light cycle.

Temperature 20-25 celcius (25 day, 20 night); constant CF extraction and a small fan blowing indirectly at one of the sides of the grow tent.

Relative Humidity is 55%

They were given Nutirents for the first time 1 week ago (only for 3-4 days) PH has been constant at 6.2.

I wasn't happy with the nutrients and became worried that they were getting nitrogen toxicity, there was also some tiny yellow/ brown dots appearing on a few leaves; so I dumped the resevoir and flushed them out with PH6.2.

They started to go very yellow. The number of spots increased, and then the size of them grew.

 

Since the flush, I have limited their watering, but given them a small amount with nutrients again (this has improved their colour).

 

I have also pulled up the lights, although it was always 18 inches away.

 

I removed a C02 bag that I put in there around the same time as the Nutes.

 

I have also become worried that this could be a pest problem > I have been unable to find any pests (top and underneath of leaves).

 

Attached are some photos of the plants, and close ups of one of the leaves.

 

 

Any advice would be welcome. I have some mite spray on hand, should this been the diagnosis.

 

Slysir.

[cultivateur 1,068]

What sort of compost is it ?

What sort of feed ? Are they hydro nutes ?

 

No need to PH with compost.

 

When you say you fed them for 3 or 4 days ... you really ought to have a wet / dry cycle.

 

Perhaps a bit of lamp burn, perhaps magnesium def ..

Edited March 13, 2018 by cultivateur

[botanics 44,210]

You've flushed the nutes out of them and caused an imbalance with the Calcium/Magnesium by the looks of it.  Possibly drowned them too in the process.

[Slysir 9]

Thanks both, I was worried that I was being a bit over attentive with the watering....

 

They're in Canna Terra Pro compost; so nutrient rich.

 

I have a 20L resevoir where I mixed only 35ml of Terra Veg in.

 

I was watering around 500ml every 2-3 days. Soil was constantly moist. It's moist today, but they look to be on the mend. I've also turned over some of the top soil to help get some air into it.

[M1PEL 463]

As already mentioned keeping the soil wet or very damp & still feeding is a no no.....you must keep a wet & dry cycle, only feed when the soil is dry...not bone dry..!....give them enough feed until you get approx 20% run off from the pots....measure how much they take So you know exactly how much feed it takes to get the run off... And only feed again when dry....If you are using good quality soil you dont need to adjust the PH.   The soil itself will buffer the PH.... If you flushed the plant with water that you PH'd ...that will cause a problem and mess with the soil natural buffer.... the lightish yellow spots you see are PH fluctuations causing lockout of some nutrients.. !  hope this helps... 

[nl5 8,806]

Should let them virtually dry out between waterings, I only water my plants once a week or less till they filled the pots out.  top few inches might feel dry but there can still be few days worth of water for the plants. Go by weight of the pots rather than how dry it looks/feels, does them the world of good to get the wer/dry cycle right.

[Slugums 4,109]

Not sure if you can turn this around - I grow in coco, so I can't really say what steps you could take.

 

For future, keep things really simple -

 

I'm not sure the co2 is worth it - if you have good extraction, its gone before the plants can suck it up.

 

You mention reservoir - water degases if left sitting... it can also get cold, neither are good qualities for the plants - this is why hydro grows use air pumps and heating in their reservoir.

 

Read a couple of grow diaries and even copy one if its close to the growing conditions you are in.

 

Wet/dry - add water slowly and aim to have 20% run off... Ditch the run-off... lift the pot to get a feel for its wet weight vs dry and do not water again until its back to its dry weight - some folks keep a pot filled with dry compost as a reference until they feel sure they have it right. Best to have a good read-up on wet/dry cycles...

 

Best of luck!

 

Oh! maybe also run a diary of your grow - folks will tag along and chip in - saved my skin on my first grow - it also helps others and gives you a great reference to look back on, unless your as random as I get!!

[GSZZ 25,048]

2 hours ago, botanics said:

You've flushed the nutes out of them and caused an imbalance with the Calcium/Magnesium by the looks of it.  Possibly drowned them too in the process.

 

It's probably worth mentioning that any sort of overwatering will probably start showing as a calcium problem due to calcium being an immobile element. When it can't be taken up by the roots because of over/underwatering its generally the first sign to show on foliage due to the relocation of energy in the plant. 

[botanics 44,210]

@Golden Syrup

 

Oh don't I know it bud, I was always buggering up little ones doing it, when in compost...I was heavy handed with the little ones and feel better when bloom time comes...the coco is better for me I'm finding

Edited March 14, 2018 by botanics

[ursus1000 1,888]

On 13/03/2018 at 1:26 PM, Slysir said:

The plants are on a 18/ 8 light cycle.

Are you sure?

[Muppet 3,121]

I'd give it a good slug of seaweed and have a search for wet/dry cycles. 

[Slysir 9]

All the help much appreciated.

 

After all the preparation and learning; I was ignorant about getting watering on point. Such a crucial element that I should not have overlooked. 

 

I’ve dried the girls out, checked the roots and done my research. They’re now getting a strict wet/ dry cycle with oxygenated water.

 

The change has been exceptional. Not only are they on the mend, but they’re growing quickly. I’m still going to give them another 2 weeks of veg before switching to 12/12.

 

Thanks again.

 

 

 

[smokie1 b c f c 5,570]

yep feeding on a wet/dry cycle, with room temp water, and the correct feed/ plus correct enviroment, and its amazing how fast they can grow. 

all the best with the flowering of your girls. 

 

[Slysir 9]

Hi All,

 

I figured that this thread is the best place to repost; I have a short update, and I've added a few extra images from today (day 35 of flower).

 

The plants recovered pretty quickly from their spell of over watering. Its not happened since, and I'm proud to say that they look very healthy - lesson learned and that won't happen again.

 

Other learnings (aside from watering) on this grow, now includes defoliation. I had 3 very bushy plants towards the end of week 3, and not a lot of space. I may have been a little over zealous with defoliation, and I believe it could have affected bud development. For future grows I fully intend to stick to one larger plant, SCROG, and do little to no defoliation.

 

The thing is, that despite this strain be pretty popular (For beginners), there are almost no grow diaries on it - Purple Bud by Sensi seed.

 

Can anyone offer any feedback on the photos from today (day 35 flower)? Am I likley to continue to see growth for the next 2-3 weeks?

 

Cheers

 

Edited April 24, 2018 by Slysir

[MyDisplayName2000 2,069]

I love an happy ending!

 

Never realised someone had nailed the problem, was going to chip in about watering too much and preventing roots from doing their job.

 

I grow in soil myself, but part of my watering ritual is to oxygenate the water as much as I can. I have 8-9 pots these days, I use a 1.2L washing up liquid bottle to get an even spread on the soil, shaking it vigorously and making sure the water is lukewarm. After that I can just pour feed by the litres until it trickles out of the pots. This way I know all the soil is watered evenly.

 

I never feed the young uns once they are in their final pot for a good 4-5 weeks. (18L pots) I feed in the second or third week of flowering, usually 3-4 weeks veg in final pot.

 

This all depends on how much stretch those plants have. If you know a variety its easier to deal with.

 

Anyhow, well done rescuing those plants. I find that plant problems always pop up now and again even to the most experienced growers.

 

Sometimes you got to swallow your pride and just ask others what the issue may be.

 

Years ago you would spend an afternoon in the library fretting over such issues. No internet you see. I guess the internet has changed how we all grow.