Chempak strength

Has anyone experience of using chempak soluble feeds. I'm particularly interested in Chempak3 and 4. The NPK seems very high for number 3 at 20:20:20. I'd appreciate your thoughts.
Thanks in advance
Morro

 

I use it, never had any problems if you follow the dilution rate.

 

Should have a measuring scoop with it,I use no.4 mostly and if i use it with every watering i only put a quarter of a measure in a 4 pt milk carton,or even less than that.

 

Aways found they left a residue in the bottom of the can , regardless of much stirring.
No idea if its actually useful or just an inert carrier ?

Generally prefer to use liquid feeds, dry ones always seem to get wasted or clumped hard together if not handled carefully.

 

I always remove it from the plastic bag and put it in various screw top jars.
One in each greenhouse and this time of the year one on top of each of the water but lids.

Its, I think the word is hydroscopic, like salt, it attracts moisture from the atmosphere, so I find screw top jars stop that happening.

 

It can be an inert carrier but also water temperature can reduce the residue.

We sell a lot of sulphate of iron but there are 2 different types, Heptahydrate and Monohydrate. Heptahydrate tends to have an (fe) between 16/20% which depends if there was any anti clumping incorporated. It takes to water more readily, but will go rock hard when exposed to moisture without any anti clumping, still ideal for spraying or when using a fine rose watering can as it dissolves in water more readily. Monohydrate has been heated and has a higher fe value of 30%, when mixed with water it will leave a residue but this can be reduced when mixing with warmer to hot water. There is likely to still be a residue but if you put it through a fine strainer then it should not be an issue.

 

I have also found this
Was wondering if this is some of the fertiliser not dissolving. Or some sort of fixing agent

 

I think it's just undisolved crystals myself. We, well I am, impatient people and don't leave it long enough.
I have noticed with liquid fertilizers that if the water is warm it goes cloudy, but it stays clear if the water is cold.

 

I put mine in a Milk Bottle and give it a good shake

 

I do wonder if there is anything stopping you mixing a batch up at something like 20 times strength and using it in a similar way to liquid feed.
Of course you would need to do the maths first to get the dilution right.

 

Trust you can explain this in laymans terms?

 

I'm not technician, I was hoping you would do the maths for me.

 

I would but recall that the chum at school whom I aided to do maths homework, progressed to become Professor In Maths at a leading university, now Vice -Chancellor on c£400k pa.(true)

 

Two scoops to 5 litres of water.

So add 20 scoops to one litre of water.

Add 100ml to 5 litres.