Cyrtanthus 2012

[jshields]

That said, my seedlings of C. clavatus are down to only a very few plants left, and they seem not to be growing.  They tend to lose their leaves in summer, where their pot sits outdoors in full sun and whatever rain we get -- not much this past summer.

With clavatus and epiphyticus, there was a quick loss of most the the seedlings that germinated, then the few survivors have tended to hang on a long time but not grow large enough to bloom.  My conditions are just barely marginal for both these species, it would seem.

Jim

[Paul T]

Jim,

So can you buy just Nitrogen fertiliser?  I'm trying to think whether I've ever seen anything here that is just Nitrogen?  There are various Nitrate fertilisers, but they are something-or-other nitrate.  I've never thought about a pure nitrogen fertilier in this way before. 

[jshields]

Jim,

So can you buy just Nitrogen fertiliser?  I'm trying to think whether I've ever seen anything here that is just Nitrogen?  There are various Nitrate fertilisers, but they are something-or-other nitrate.  I've never thought about a pure nitrogen fertilier in this way before. 

Paul,

I use a soluble fertilizer, 20-10-20 with micronutrients.  You can get pure "nitrogen" in fertilizer (i.e., no phosphate and no potassium) by using things like ammonium sulfate, ammonium nitrate, sodium, calcium, or magnesium nitrate, etc.  Some people do use such things, for specific purposes; farmers use liquid ammonia on their fields, for instance.  For growing bulbs, we need to have a reasonable balance of N, P, and K.  For most bulbs, I suspect a very good balance would be 20-5-15, since that tends to reflect the elemental composition of most bulbs.  I can get 20-10-20 readily, so that's what I use.

For Nerine, I tend to use a nitrogen-free mix based on potassium phosphates and potassium sulfate, which ends up being about 0-15-35 more or less.  That is the only exception I can think of to the balanced feeding rule.  Even the Nerine need a little nitrogen, of course, but a normal nitrogen feeding tends to induce virus-like symptoms in some of the broad-leaf Nerine species and hybrids.

Jim

[Paul T]

Thanks Jim.

Very interesting comment re the Nerine leaves.  Do you think it is causing the exhibition of underlying virus, or causing leaf distortion that mimic virus symptoms?

[jshields]

Thanks Jim.

Very interesting comment re the Nerine leaves.  Do you think it is causing the exhibition of underlying virus, or causing leaf distortion that mimic virus symptoms?

Sir Peter Smithers thought the higher nitrogen levels released a latent virus carried in the broad-leaf nerines' DNA.  Several other experts scoffed at the virus idea.  Nevertheless, growing bowdenii or sarniensis with normal nitrogen levels in fertilizers seems not to be good for them.  I actually tested the idea, and got plants with mottled and distorted leaves.

Jim

[Paul T]

Absolutely fascinating.  Thanks for the info.

[daveyp1970]

Sir Peter Smithers thought the higher nitrogen levels released a latent virus carried in the broad-leaf nerines' DNA.  Several other experts scoffed at the virus idea.  Nevertheless, growing bowdenii or sarniensis with normal nitrogen levels in fertilizers seems not to be good for them.  I actually tested the idea, and got plants with mottled and distorted leaves.

Jim

Jim Sir Peter Smithers was a very forward thinking chap because i am convinced his theory is right but not just Nerines as with all plants and as part of a plants evolution viruses are entwind. I hope that makes sense.But i just can't imagine everybody burning or binning there plants and when a plant lives with it comfortably that's why they laughed(see no evil 

[johnw]

Jim -   I have to agree.  In the early days I did give my nerines regular feedings and saw virus-like streaking.  In a letter Sir Peter warned me and I reduced the N to about 1/8 strength once or twice a year and the symptoms disappeared.  Can't blame aphids or other insects for virus transmission as I've never seen a bug on them.  Now the get mainly P & K 1/4 strength 3 to 4 times.  Amazing how they tolerate nearly sterile mixes of peat, gravel, sand and a bit iof leafmold for years.

johnw

[Hans J]

...the problem seems for me to find a fertilizer without N ....here in Germany is it not aviable 

[jshields]

Hans, I make my own.  Get, from a chemical supply house, KH2PO4 (i.e., monobasic potassium phosphate), K2HPO4 (dibasic potassium phosphate), and K2SO4 (potassium sulfate).  They do tend to be expensive in chemical reagent grade.  You might try getting them (in relatively huge amounts) from agricultural suppliers; these compounds do make good fertilizer, after all.

Mix thoroughly one part (by weight) KH2PO4, one part K2HPO4, and 2 parts K2SO4.  This gives something in the range of N-P-K  0-15-35 (more or less).

You could make these sorts of fertilizers from sodium phosphates and potassium chloride, which are cheaper; but when mixed they produce an equal amount of sodium chloride.  Cheap fertilizers likely are made just this way in commerce.

Jim

[Hans J]

Jim -thank you for your advices

I have in menatime found "Thomaskali":
http://images.raiffeisen.com/Raicom/Images/Geno/drwz/dateien/HG_DB_GK_11_Thomaskali_GKTH.pdf

Could you please look if that would work ...I'm not shure because there is a lot of Calcium Oxid ( 20%)
I dont know if this is well for bulb plants ...

Thank you in advance
Hans

[jshields]

Jim -thank you for your advices

I have in menatime found "Thomaskali":
http://images.raiffeisen.com/Raicom/Images/Geno/drwz/dateien/HG_DB_GK_11_Thomaskali_GKTH.pdf

Could you please look if that would work ...I'm not shure because there is a lot of Calcium Oxid ( 20%)
I dont know if this is well for bulb plants ...

Thank you in advance
Hans

Hans,

That fertilizer looks OK for nitrogen-free feeding.  It does not actually contain CaO (calcium oxide) which is very strongly alkaline.  It does have other basic (alkaline-reacting) materials, probably calcium carbonate, so watch the pH of any soil you add it to for gradual changes.  Bulbs do indeed need substantial amounts of calcium and magnesium besides the N, P, and K.

In cases like this where one is using a new (to them) material, use cautiously, first only on a few sample plants, until it can be seen that it does not cause any harm.

Jim

[Hans J]

Thank you Jim ,

If I use this PK fertilizer would be 1 gram per liter OK ? ( 8% P + 15% K )
On the description is only 80-100gram per m2 written ...

I'm on the right track ?
Hans

[jshields]

Hans,

Yes, you are on the right track.  If this material is soluble, then about 1.0 to 1.2 grams per liter of water would be right.

Jim

[Hans J]

Jim - thanks !

I have now made a solution to test if it is well soluble ...

Hans