Low nitrogen - what does it mean? What are some examples

[tuscanpistoia]

Hi everyone, i've been going over my species notes lately, and it seems it's coming to that time to start feeding low nitrogen fertilizers. However I've found it quite difficult to find fertilizers where the N in NPK was lower than the rest - the nearest I got was liquid sulphate of potash that had none. Soooooooo, for us fertilizing novices - what exactly qualifies as 'low nitrogen' and what types of fertilizers normally are low nitrogen. If possible could you give some examples of specific fertilizers (ideally those that bunnings would stock)

[Ash]

Any of the inorganic fertilizers tagged with 'flower' or 'fruit' would fit that description. Examples of soluble inorganic fertilizers that would be tagged 'low nitrogen' are Searles Flourish, Grow Force Nine or Grow Force Seven, Cultiplex, Thrive Flower and Fruit. There are many more, any of those specifically marketed as 'flower boosters' to Orchid growers would fit that description.

cheers
Ash

[tuscanpistoia]

Thanks Ash, that is really helpful. I shall be looking at these over the next week.

Cheers,

[shibui]

From your post I gather you have checked the N:P:K numbers on the fertiliser packets which is a good start. Low nitrogen does not mean the N ratio will be close to 0. As you have discovered such a fertiliser is rare. Low nitrogen means the N ratio is lower than normal so the numbers for N will be getting closer to the P and K. I prefer to talk about using higher K fertilisers for autumn rather than stressing low N.
A look in my shed revealed the following fertilisers:
Campells orchid fertiliser for growth N=30; P=4.4; K=8.3. Very high N levels, almost 4xK. Designed to boost growth and produce lush green leaves.
Campells orchid fertiliser for flowers N=11.8; P=13.2; K=16.6. N ratio very low. Both P and K higher than N
Thrive: N = 27; P = 5.5; K = 9. N is 3 x K. This is a high nitrogen fertiliser designed to boost growth and make foliage lush and green.
Thrive soluble for flowers and fruit: N=15; P=4; K=26. Another low N, very high K so good for autumn fertilising.
Osmocote soluble: N = 28; P= 1; K= 14. This fertiliser is very low P so is safer for P sensitive plants like Banksia and protea.
Fish emulsion: N=3.3; P=.6; K=.33. Although the N number is quite small it is 10x K so this is really a high N fert. Recommended strength is only 2-3 times the ones above so still doesn't give quite as much N to the plant when used at that rate and would probably be safe at twice the recommended rates.
Charlie Carp: N=10; P=2; K=6. Nitrogen is less than 2x K.
Maxicrop (liquid seaweed): N=.053, P=.063; K=.18 (note this is quite old liquid seaweed. I don't think they supply NPK anymore so call it a soil conditioner instead of fertiliser ) N is less than 1/3 of K so very low N but also very low P and K so you need to put a lot on to supply adequate nutrients. that's why it is sold as a tonic rater than fertiliser but would still be good to use through autumn in conjunction with other fertilisers.
Organic Life: N=4; P=3; K=2. This is a pelletised chook poo with added seaweed and other manure, etc to give a more balanced product. N=2xK so still relativey high N for growth. With low numbers like that you can use quite a lot without causing the plants problems as we have seen in the fast growing thread on figs. p is relatively high so take care with banksias.

As Ash has said, you should find that any fertiliser sold for flowering and fruiting plants will have relatively low N. Check tomato, citrus, azalea fertilisers as well as the ones already mentioned. these can also be used with flowering and fruiting bonsai to boost flowering.

Note that even the high analysis fertilisers have quite a lot of nothing in them eg Thrive 27% + 5.5% + 9% = 41.5%. even allowing for the trace elements only half of the pack is useful to the plants. Fish emulsion 3.3+.6+.33 = 4.23% useful. The rest is water, organic matter and other stuff that isn't fertiliser. Those with an organic leaning will argue that much of the 'other' in organic products is beneficial though we cannot measure it.

[NBPCA]

In way north North America zero nitrogen ferts may be used ((0-10-10) for instance to set the tree up for the long winter.

I think zero or low N ferts for your part of the world are not necessary.

Grant

[Greth]

Most fertilisers list their content as N-P-K.
The cheat for beginners is to remember leaves-flowers-fruit = N-P-K. Not fantastically accurate, but if you want high nitrogen, leaf promoting fertilisers, look for stuff that is promoted for grass. If you want low nitrogen, look for stuff which promotes fruit and flowers.

[senseijames]

G'day all, thought i would put my worth in, I fertilize twice a week and my plants are thriving, usually on thursdays I use 25 ml Powerfeed mixed with 75ml Seasol in 8 ltrs water, and on Sundays I use 2 tablespoons Scotts " Miracle-Gro All Purpose granular plant food in 8 ltrs water, I use an 8ltr Hozelok Sprayer with the nozzle hole drilled bigger so the liquid flows out better. For winter I will use Manutec Bloom Booster N 6.2-P 14.6-K 16.8 instead of Scotts " Miracle-Gro All Purpose N 15-P 13.1- K 12.4, because it has less nitrogen content.
Cheers
James

[Ron]

....I use an 8ltr Hozelok Sprayer with the nozzle hole drilled bigger so the liquid flows out better.

Hi James,

Which one do you use?

http://www.hozelock.com/spraying.html

I used 9l water cans for fertilising etc but I end up with a lot of pain especially in my back for a day or two. Perhaps on these sprayers might be the answer for me.

Ron ...

[senseijames]

Hi Ron, mine is an 8 ltr it is a fair few years old now, if you check out the link below this is the latest equivalent from the Australian distributor in Brisbane I recommend this Company as I have dealt with them on a few occasions and they are good blokes, very fast and efficient service.
http://www.rockaroundtheblock.com.au/pr ... 16&cID=140
Hope this helps........Cheers mate
James
PS Just thought...get yourself a spare nozzle for the job because you have to drill the hole bigger and it wont be any good for mist or fine spraying anymore.

[Bretts]

I never usually bother with high PK ferts but wanted it for the tallow at least this year. There is little selection but I found a hydroponic one called P13 K14 at Bunnings. That should do the trick?