Phostrogen

Anybody else use this? I use this for everything (I don't grow veg) for small potted plants I just do the pinch in a pint routine, seem to get really good results, my fuchsias used to have HUGE flowers. Any other fertiliser which you find preferable??

Val

 

I used it last year, very good results.
This year, I am using it again, alongside tomato feed.

 

I use Phostrogen and cheapo tom food . In the house for my plants and seedlings Baby Bio.......

 

I used to use it, but have now switched to Miracle Grow soluable feed (24:8:16) for plants whist growing and then I use Chempak Potash feed (and sometimes Chempak Tomato) once the plant is flowering as I find that cheaper than regular Tomato etc. fertiliser

Phostrogen is 14:10:27

Chempak #4 High potash is 15:15:30 (makes 1,600 Litres for £8.99)
Chempak Tomato is 11:9:30 (makes 1,200 Litres for £9.99)

 

Phostrogen is essentially the same as tomato feed, being high in Potassium, which is good for fruit and flowers. So I don't think you need both. Also its cheaper, being a solid.​

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I posted this in 2007. I think it is just a relavent today, except that the prices will be higher.​

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I have just visited my local Homebase and recorded the figures from all their fertilisers for sale. the columns below are, manufacturer, product, NPK ratio, and cost in £ per kilo of active ingredient. I have added the N, P and K together to give a total of active ingredients. The results are :=​

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Plant feed​

JAB --------- Sulphate of Potash 1.3kg --- 0,0,48 ------ 3.67​

JAB ----------Growmore - 4kg ------------ 7,7,7 ------- 4.75​

Bayer --------Phostrogen - 1.25kg ------- 14,10,27 ---- 5.47​

Bayer ------- Phostrogen - 2kg ---------- 14,10,27 ----- 5.87​

Miraclegrow - all purpose - 2kg ----------- 24,8,16 ------ 6.24​

Miraclegrow - all purpose - 1kg ----------- 24,8,16 ------ 7.27​

JAB --------- Blood, fish and bone - 4kg -- 5,5,6.5 ------ 7.56​

JAB --------- Sulphate of ammonia - 1kg -- 21,0,0 ----- 10.90​

Westland ---- liquid - 2 litre -------------- 5,2.5,10 ---- 11.40​

JAB ----------Bone meal - 4kg ------------ 3.5,7,0 ----- 11.88​

Bio --------- Top rose - liquid - 1 litre ---- 5,6,12 ------ 13.00​

Miraclegrow - slow release - 1 kg ----------18,9,11 ----- 13.13​

Homebase --- tomato feed - liquid - 2 litre -3.9,2.6,7.7 -- 17.57​

Levington --- Tomorite - liquid - l litre ----- 4,4.5,8 ------ 21.15​

Miraclegrow - slow release tablets 165 g ---10,11,18 ----- 62.00​

Miraclegrow - liquid feed - 0.57 litre ------ 12,4,8 -------- 73.03​

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Lawn feed - virtually all nitrogen.​

Miraclegrow - lawn feed - liquid - 2 litre - 36,6,6 --- 8.32​

Miraclegrow - lawn feed - liquid - 1 litre - 36,6,6 --- 10.40​

Evergreen --- lawn feed - liquid - 1 litre - 24,0,0 --- 24.96​

Evergreen --- lawn feed - spray - 100 cc 27,0,1 --- 213.93​

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You can pay anything from about £5 per kilo to over £200 per kilo. The choice is yours. Be aware that the NPK values differ. Some like the Sulphate of Potash are very specialised being pure potassium. You need to get the balance right for your purpose. The absolute NPK figures tell you how much the active ingredients cost you. But the balance between them tells you in what way they will help your plants to grow. There is probably no difference in cost betweeb N,P and K as chemicals, so the difference in price is due to solid/liquid, brand name and size of package. Overall Growmore came out as very good value, but it is not so easily dissolved in water. Phostrogen (high potassium)and MiracleGrow (balanced feed) are easily soluble, and come out as the best overall.​

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Roders the answer to your original question as why Tomerite is so expensive, is that it is a liquid. You are mostly paying for water. Phostrogen is a quarter of the price, and just as good.​

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If you want to be a cheapskate, like me, you can use Miracle grow, which is cheaper even than Phostrogen, but not as high in Potassium. Then just add Sulphate of Potash (ie pure Potassium), which is even cheaper still. In mixing your own, you are doing exactly what the manufacturer does. The benefit of using something like Miraclegrow as a base is that you have all the other trace elements as well.​

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So Peter it is OK to use Phostrogen all the way through the season instead of changing to Tomato food in August ?
I have your super table above saved on an excel sheet . I was wondering last week as Phostrogen is so high in K why use Tomato feed . I think the post above answers it.
So I can use Phostrogen from feeding my pricked out seedlings at a 1/4 strength all the way through to October. This will make life simpler , and cheaper !

 

You can use Phostrogen instead of Tomato food for your flowering plants (Tomato food probably better for Tomatoes as its trace elements may be better suited to Toms, and maybe other similar fruiting veg)

Personally I think you would be better off with something with more Nitrogen earlier in the season. You don't want so much Nitrogen that the plants don't bother to flower! but if you are worried about that you can just use Nitrogen-rich fertilizer for N-weeks and then switch to Phostrogen to encourage flowering.

Worth looking at Miracle-Grow for the early-season I reckon.

And personally I would look at Chempak for the Potash for flowering later on, as I reckon it will be cheaper (but I've not done a comparison against Phostrogen; both are powder-based so will be a lot-lot cheaper than a liquid based fertiliser, which many Tomato fertilisers are.

 

I've always been sceptical about Phostrogen, dont know why.
I think it was the first all purpose plant feed I came across and its claims at that time were unbelievable.

I've used Miracle grow, but for toms I still like Tomorite, OK its probably expensive, not so bad if you buy it in Morrisons, but it just looks better.
I only grow outdoor toms so feeding is minimal.

I did go down the Chempak road for a while, but its not readily available since it was taken over, I believe.


I do use straight fertilisers like Sulphate of Ammonia, and Sulphate of Potash, even Superphosphate.
Chicken doodar as a top dressing and even bought a couple of boxes of fish, blood and bone in Morrisons for £2 each.

 

Harry - I think it is very difficult for any of us to know exactly what works best and when, without doing a lot of trials under strict laboratory conditions. In the absence of this we all have our favorites and I am no exception.

My understanding is that the major chemicals, ie the salts of Nitrogen, Phosphorous and Potassium are very simple chemicals and are all essentially the same, irrespective of the name on the box. They are probably all bought in from the same chemical manufacturer such as ICI (as was). What's important is the ratio. As Nitrogen is good for foliage growth, as Kristen said, I use Miraclegrow early on in the season before the plant starts to flower. As Potassium is good for flowers and fruit, I switch to a high Potassium feed later in the season when things start to flower.

Its my understanding that Tomato feeds such as Tomorite and Phostrogen are essentially the same thing - both being high in Potassium. There will be small differences in the trace elements that are included, but I can't judge the effect, if any, of that. I suspect the major difference is in the marketing.

I think its a bit like food for us humans. Some people swear by pasta, other swear by curries, and some people are vegetarians. But as long as we get enough food, vitamins and trace elements, and a good balance - you can't really say any one person's eating habits are better that another's.

 

Dunno if it adds anything to the discussion? but Tomorite doesn't have enough Magnesium to prevent container grown Toms needing Epsom Salts most years, in my experience!! and Miracle-grow doesn't have any Magnesium at all, which may be fine for container grown annuals in compost that already has enough, but I think it would be worth giving Epsom salts to anything being fed on Miracle grow - say: a couple of times in the season

 

The fertilizer manufacturers assume the shortfall will be made up from the source water or the soil. Its best to wait until you see symptoms before you go adding extra stuff as it can do more harm than good if its not needed.
Potassium sulphate is very potent stuff, if you go overboard you`re likely to see some calcium and magnesium issues. Dont forget you`ll add a goodly amount of sulphur (S) along with the potassium (K), 1g in 1L of water adds 400ppm of K and 163ppm of S.
The standard dilution rate of 14-10-27 phostrogen (10g per 4.5L) provides almost 500ppm of K which is plenty.

 

I picked up some of the miracle grow sachets yesterday, one sachet to 4l of water.

This year I'm using the phostrogen, the tommy food and the miracle grow. I don't know why I'm using all 3, but hey, why not?!

 

Thanks for all the answers . I normally use Miracle-Gro followed by Tomato food later in the season . I'll try Phostrogen all season this year , and see if there is any marked difference , plus or minus.

 

You going to do some plants with each "regime" to compare them side by side?

otherwise a bit tricky to know if it is the season, or the feeding, that makes the difference

 

Well I was thinking of setting up a full Taguchi Design of experiment to determine the best regime - or- I could just read the back of the packet and trust that.