# How much TSP?



## DeepC (Aug 12, 2020)

Can someone please help me raising my phosphorous? My soil test showed to be low in Phosphorus coming in at 18 lbs/acre. I have purchased a 50lb bag of Tsp-Triple Super Phosphate 0-46-0. I have looked in the Soil Remedeation Guide and it says you can add 2 lbs per month during the growing season. I am in Texas and I have bermuda that is 90% dormant now so I was thinking (hoping) maybe I could add more than that amount to bulk up for spring to start off at the desired level. Can someone help me figure out how many pounds of phosphorous I need to add to be at the perfect level? And how much can I add now? Thank you so much for any guidance you can give me.


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## Ridgerunner (May 16, 2017)

Every 1# per thousand square feet of P2O5 should increase P levels by about 18 lbs per acre. 0-46-0 is 46% P2O5. 2.17 lbs of 0-46-0 per thousand square feet will = 1# of P2O5.


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## g-man (Jun 15, 2017)

If your soil never gets frozen, then you can apply the 2lb of TSP/month every month. Your value is low, but it will take a long time to get it into a good spot. Don't try to rush, this is a marathon and you can have a nice lawn with have you have.


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## Ridgerunner (May 16, 2017)

Just noticed your pH. At 8.4, much of the P is going to quickly get tied up in unusable forms. No advantage to putting down large quantities to hit some "ideal" max level. Better to try to insure P availability to the turf by spoon feeding on a constant basis.


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## DeepC (Aug 12, 2020)

@Ridgerunner , Thank you so much for your help. I will see if I can dissolve the TSP in water to see if I can spray it to spoon feed. Assuming that's what you mean. I'm going to be using T-nex this coming season so I could spoon feed in those applications.


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## Ridgerunner (May 16, 2017)

By "spoon feeding", I mean small doses, more often. For example: applying 1/2#- 3/4#/M of granular 0-46-0 product every 2 weeks or, more realistically, 1 to 1 1/2#/M every month during the growing season (about double what the turf will use) rather than 2- 3#/M at a time in the Spring and Fall that some labs might recommend for curing a deficit. Turf needs about 0.25 to 0.4 lbs of P2O5 for every 1 lb of N used. Any P amount above what the turf uses will contribute to soil reserves/insurance of availability or in high pH or very low pH soils, get locked up in unusable forms.
Spaying is not in my wheelhouse. @g-man may be able to advise you on that.


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## g-man (Jun 15, 2017)

You can spray some of it, but to address your soil issues, go with granular.


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## DeepC (Aug 12, 2020)

I have been trying to find MAP Monoammonium Phosphate too but I haven't had any luck?
I may have to pay a fortune for it online. Any suggested sources for ordering it online?


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