K-Lite experts, please help

[Trithor]

I am trying to change my fertilising, but have had a few unpleasant starts. Now that my greenhouse is starting too smell less like a bad fish market, and more like that accustomed jungle smell, I have new energy to try and resolve the problem.
Originaly when I was using my previous fertilizer as a foliar feed only, I was getting great results, but as the collection grew, that no longer was feasible, so I switched to fertigation. It was then that I noticed my plants going backwards (leaf tip die back and a high incidence of flower deformity, as well as slow growth). It is only now after reading the posts on this forum that I had a look at the chem comp of the product and I see that the potassium is stratospheric.
My next attempt was even worse (dont ever use a fish product in your greenhouse!)

I can get a hydroponic formulation 3.2.1(19) with ME, would this be appropriate and what should I add to improve the balance (Mag sulph and Ca nitrate have been mentioned)

 

[Stone]

Trithor, By all means try low K low P type of formulation but please first realize that leaf tip burn was not caused by excessive K. Much more likely it was high overall Total Disolved Salts ( high salinity ) which caused that issue or something you have not mentioned. Therefore I strongly recommend you purchase an EC meter from you hydroponic supplier so you can monitor the strength of your feed. I suggest starting with an EC of about 0.5 dS/m or lower regardless of the formulation. If you want to increase Ca and Mg, add the nitrate and sulphate forms to bring EC up to 0.9 and dilute back to 0.5 with more water. Mag sulphate should be about 1/4 of the Nitrate. Or use just these two nutrients every other feed. Or just order some from Ray! This will reduce all the minor elements as well but the plants probably only need much less than what we give them anyway.

 

[emydura]

I personally find the application of a foliar fertliser so much easier than fertigation. I just need to fill up my 5 litre sprayer once and that does my whole glasshouse (I mix 4L actually). I do fertigate every 4th watering. It just happened to be today actually. I had to mix four 9L watering cans to cover my glasshouse. It is a lot more work for me and heavier as well. And like you I'm very happy with the effect of the foliar fertiliser.

 

[Ozpaph]

Flush a lot.
Lower fertilizer concentration - use a TDS (or similar) meter.
I alternate various fertilisers (lowish K) and add MgSo4 and Cal Nitrate

 

[Trithor]

Perhaps I should give more details of my problem.
I water twice a week, once during the week (midweek, at about 7am). This watering is with plain council tap water, but the watering is very thorough, I allow the water to drain liberally through the pots. I don't worry about wasting water as the greenhouse is tiled with terra cotta tiles and all the runoff collects in a big tank which I use to water the lawn and garden. The second watering is over the weekend and is done in two stages, the first at 7am, as above with council water, and then I go to breakfast, and about an hour later I rewater with a mix of council and RO (winter) or rainwater (summer)
I mist with trace elements once a month, and fertigate once a month. The fertigation solution is mixed to half recommended strength (the concentration was lab checked when I calibrated the fertigation system)
As late summer approaches I substitute the trace element session with a fungicide as I have found that as we get cooler wet days before the onset of winter, fungal problems do manifest themselves, so I opt for a preventative treatment for two months (early autumn, and early winter)
I do not feed during mid winter or mid summer)
A portion of leaf tip die-back was as a result of a potting mix which I switched to. I started to use coconut husk chips, as good bark was not available. These coconut chips degraded to a mush over a six month period. The surface of the pot still looked great, but the problem lurked in the bottom of the pot.
When my collection grew to in excess of 5k plants, foliar feeding became too time consuming and so I switched to fertigation.
Not all my plants show problems, but the few that do, concern me (perhaps 2%)
What I have noticed which is far more worrying is that plants which previously had great flowers, became recalcitrant bloomers, or showed floral defects not present before. The most affected with defects were the multis, particularly those with roths and stonei in their background. Again it is not all of them, and also not consistent. A multi which won 'best on show' at our nationals last year had two perfect spikes, but the third spike which opened about a week after the show was so deformed that it nowhere resembled the previous blooms.
I am also not happy with the last two seasons growth ( about when I switched to fertigation, also when I changed to the new brand of fertilizer) I strongly believe that the excessively high K is partly if not completely to blame. I have been blaming the incorporated auxins until now, (still not happy with auxins in the fertilizer)

 

[DavidCampen]

I am also not happy with the last two seasons growth ( about when I switched to fertigation, also when I changed to the new brand of fertilizer) I strongly believe that the excessively high K is partly if not completely to blame. I have been blaming the incorporated auxins until now, (still not happy with auxins in the fertilizer)

Why have you switched from blaming the auxins to blaming potassium? What was the composition (NPK, types of nitrogen, calcium, magnesium levels) of the fertilizer that you were using for foliar feeding compared to what you are using now for fertigation? When you changed from foliar feeding to fertigation why did you change fertilizers?

 

[gonewild]

I mist with trace elements once a month, and fertigate once a month. The fertigation solution is mixed to half recommended strength (the concentration was lab checked when I calibrated the fertigation system)

What is the recommended strength for feeding once a month?
Does your fertigation solution contain any trace elements?

As late summer approaches I substitute the trace element session with a fungicide as I have found that as we get cooler wet days before the onset of winter, fungal problems do manifest themselves, so I opt for a preventative treatment for two months (early autumn, and early winter)

This is a disease problem that low potassium levels seems to eliminate.

I do not feed during mid winter or mid summer)

You feed once a month so that would be 12 applications?
And then you don't feed mid during mid winter or summer, so how many fertilizer applications do you actually apply in a year?

What I have noticed which is far more worrying is that plants which previously had great flowers, became recalcitrant bloomers, or showed floral defects not present before. The most affected with defects were the multis, particularly those with roths and stonei in their background. Again it is not all of them, and also not consistent. A multi which won 'best on show' at our nationals last year had two perfect spikes, but the third spike which opened about a week after the show was so deformed that it nowhere resembled the previous blooms.

Deformed in what way?
Do you see flowers wilting in a short time?

I am also not happy with the last two seasons growth ( about when I switched to fertigation, also when I changed to the new brand of fertilizer) I strongly believe that the excessively high K is partly if not completely to blame.

That is the conclusion k-lite users are reporting (proving). But there are other possible reasons also for the problems you have. The high potassium levels may not be the actual cause but they may very well aggravate the problems.

I have been blaming the incorporated auxins until now, (still not happy with auxins in the fertilizer)

What auxins are in the fertilizer?

 

[Stone]

What auxins are in the fertilizer?

Or more to the point WHY are auxins in the fertilizer?

 

[Ray]

Foliar feeding of trace elements????? Why? A very slim, periodic addition to the fertigation solution is plenty. Excessive trace elements often lead to confused symptoms of other nutritional issues.

I also doubt the auxins are playing a role. For one, they can be very unstable, so when incorporated in a fertilizer formula kept at room temperature, they'll likely degrade readily.

 

[gonewild]

Or more to the point WHY are auxins in the fertilizer?

That would be my next question!

 

[Trithor]

I have no idea what the cytokinins and auxins are in the formulation, or why they are included. It is a ready made hydroponic/foliar/fertigation feed for use in greenhouses on flowering plants and fruit.
The formulation is as follows;
Nitrogen 141g/kg
Phosphorus 46g/kg
P2O6 105g/kg
K 275g/kg
K2O 331g/kg
Sulphur 13g/kg
Magnesium 2g/kg
Zinc 500mg/kg
Iron 500mg/kg
Manganese 200mg/kg
Copper 200mg/kg
Boron 1g/kg
Mo 50mg/kg
Cytokinins 34mg/kg
Auxins 57mg/kg
Above is mixed as 200g per 100liter stock solution and applied at a mix rate of 1 in 100 fertigation

The blooms do not seem to fade quickly at all, I cannot claim that that has posed a problem.
The deformities are deformed pouch on some, others have a deformed dorsal, and some the one petal is fused to the dorsal. They are significant deformities, not just a slight distortion. Some blooms are so deformed that it is a struggle to identify the flower as a paph, and absolutely impossible to discern what the actual hybrid or species is. The deformity is not constant, from one spike to the next on the same plant (both from one flowering to the next, as well as at the same flowering)
I feed arround 11 times a year (4 weekly intervals, but do not feed mid summer or mid winter unless the weather is a bit cooler in mid summer or a bit warmer in mid winter. I have noticed that growth rates are lower at both these times and so reduce the feed accordingly.
I mist with a trace element mix (mist= very light application) once a month, as the trace element mix contains a broader range of elements incl silicon. When I starded with this I did see an improvement in growth quality and rate (the growths seemed firmer and larger, and also seemed to mature quicker)

 

[Stone]

So if I understand that correctly, your actual NPK is 14.1%-4.6%-27.5%.
If thats the case, It falls within the general ratios of your ''normal'' type fertilizers.
I see no Ca, so you should add that as nitrate which would bring your N level higher, Reduce your P/N ratio (a good thing) and reduce your K/N ratio as well as adding Calcium.
But I really don't know if I like the idea of hormones added to the feed. It might be worthwhile finding a different one?
Also, an interval of 4 weeks is probably too long for a liquid feeding program. I would suggest a weekly feed at 1/4 of the normal rate. Again, an EC meter is a handy tool.

 

[gonewild]

Potassium is WAY to high.

I would not use fertilizer that contains auxins. Not knowing what the auxins are it is difficult to comment but they could very well be the cause of the flower deformations.

You need a different fertilizer formula.

You are applying 200 grams of fertilizer in 10000 liters of water, how many total ppms is this?

 

[Ray]

Actually, in standard fertilizer parlance, it's a 14.1-10.5-33.1 formula, but at 200g in 10000 liters (200,000mg/10,000kg), that's only a 20 ppm total addition, which makes me think that the fertilizer and the hormones (if we assume they are active) are playing no role.

 

[DavidCampen]

AS ray says, the fertilizer solution you are feeding with is only 20 ppm. And, you are only feeding with this once a month. This is such a small amount that whatever your problems are they are not caused by you fertilizer formulation. You could replace this fertilizer with pure potassium chloride or pure table salt and at 20 ppm once a month it won't have any effect. Most of your mineral nutrition is likely coming from the council water that you use weekly and your potting media.

I believe that you said that this fertilizer concentration is 1/2 the recommended concentration; but remember that that recommended concentration was likely intended for hydroponic use where the roots have constant contact with the solution. If you are going to feed at 20 ppm TDS then you should do it with every watering; then you also need to know the analysis of your council water to determine if you should add calcium and magnesium.

The level of boron in this fertilizer formulation is also curiously high - twice the level of iron but I guess that it won't hurt anything.

 

[gonewild]

Actually, in standard fertilizer parlance, it's a 14.1-10.5-33.1 formula, but at 200g in 10000 liters (200,000mg/10,000kg), that's only a 20 ppm total addition, which makes me think that the fertilizer and the hormones (if we assume they are active) are playing no role.

I've never use K2O but....

Doesn't

K 275g/kg
K2O 331g/kg

come out to be 550 g of K?
Doesn't that make 55% K?

 

[gonewild]

Your nutrient level is low based on the amount you apply. Previous logic would say the fertilizer is not your problem.

BUT since the use of K-lite is giving us new insight into nutrient levels for orchids we shoud not make this assumption.

I have known for a long time that the correct ratio balance between nutrients was more important than the amount applied to orchids. Until k-lite use revealed that rapid growth can be achieved with very low nutrient levels we did not know how little nutrients orchids actually need.

Even though your fertilizer applications are very low in nutrient content they are out of balance. It is very likely that at low nutrient levels the balance between nutrients becomes more critical.

Based on the short time but posttive results of K-lites low K ratio I still maintain your potassium levels are way to high and could be a source of toxic conditions.

That said your deformed flowers point to environmental factors. Possibly atmosphere pollution. Ethylene Gas?

Excess Auxins and Cytokinins in the environment become environmental pollutants. Unless you know how and why to use them you should not apply them.

When you fertigate do you wet the foliage and flower spikes? If you do this could explain why one flower spike is deformed and others not. Applying auxins during a certain stage of bud development could easily cause deformation. Possibly this could happen also by a sudden increase taken in by the roots.

 

[DavidCampen]

I've never use K2O but....

Doesn't

K 275g/kg
K2O 331g/kg

come out to be 550 g of K?
Doesn't that make 55% K?

They are giving the amount of potassium in two different ways - as the weight of potassium and again as the weight of potassium oxide; 275g K equals 331g K20. In the U.S. the K of N-P-K is expressed as the weight of K2O. K2O would not be in a fertilizer formulation - it would react violently with water, except that it wouldn't last that long since it would quickly react with ambient moisture to form KOH.

 

[DavidCampen]

Even though your fertilizer applications are very low in nutrient content they are out of balance. It is very likely that at low nutrient levels the balance between nutrients becomes more critical.

That reminds me of a joke I already told here - about the homeopath who forgot to take his medicine and died of an overdose.

And anyways, he is watering weekly with council water which likely contains a substantial amount of calcium and magnesium and is much greater than the small amount of K from his fertilizer.

 

[gonewild]

That reminds me of a joke I already told here - about the homeopath who forgot to take his medicine and died of an overdose.

And anyways, he is watering weekly with council water which likely contains a substantial amount of calcium and magnesium and is much greater than the small amount of K from his fertilizer.

I don't like to make assumptions about water supply content. Unless we know what is in the council water we can't assume it has a substantial amount of anything.

The weekly water applications do not offset the nutrient imbalance that occurs once each month. In fact it increases the problem. Plants like orchids need a steady consistent supply of nutrients. You can't expect living tissue to be happy with only feeding once a month. At best it causes a sudden growth spurt that gets starved to death for the next 30 days.
When I speak of balance of nutrients it is in a multi dimensional view, balance between available nutrients as well as being available at all times for tissue growth.