Masterblend 4-18-38 question for tomatoes in potting mix

[dshreter]

No, I don’t have it in hand! pH is around 8 here, and I grow in Pro Mix HP. What would I be targeting as optimal?

[AKmark]

Originally Posted by dshreter

No, I don’t have it in hand! pH is around 8 here, and I grow in Pro Mix HP. What would I be targeting as optimal?

The fertilizer itself with the correct blends of N can lower pH on its own, if the tap water is not too basic that alone can be enough for some. We have to use acid on top of that. I use 55 percent Phosphoric acid, it does not affect antagonism or cause any precipitation with Ca and S. We shoot for a 6.5 when growing seedling and a 6.2 with mature plants.

Many don't know, but we just don't grow tomatoes, we have a large retail center. We have several thousand people come through every year, we do sessions with the state Master Gardeners programs, we do tours, and have an information center where people can learn. We are a full service GH and setting up home hobby growers is what we do, weather it be organic twists or synthetics in containers. We are also in a huge loop, we can call or send samples to labs, I have white coat support everywhere, we are also under scrutiny of the USDA, DEC, EPA, etc, etc. In short, T's crossed I's dotted daily, and we try to pass along high value information so people are successful and HAPPY. The last three words all go together.

In short you can add pH down to your fert tank, I put mine by itself.

[dshreter]

You are a wealth of information, I’ve made a lot of my own plans based upon your grow threads! Do you measure your pH from runoff to account fir the medium or the fetigation solution? I’m growing in mostly peat which I understand is acidic, so I assume needs to be factored in?

[AKmark]

Originally Posted by dshreter

You are a wealth of information, I’ve made a lot of my own plans based upon your grow threads! Do you measure your pH from runoff to account fir the medium or the fetigation solution? I’m growing in mostly peat which I understand is acidic, so I assume needs to be factored in?

We just pass on information, others figure this stuff out first. lol I measure what goes in, and I also have a soil stab that I use more for flowers like Geraniums. You will water very often, largely we control our issues with that. The farmer who has thousands of acres cannot do that, he uses different blends of N to control pH with his fertilizer. We have tomatoes in containers from March to late October and they are mostly same consistent if you leach out a tiny bit. It's a long season in a container and we are not seeing much drift.

Keep us posted on your results, enjoy the season.

[zipcode]

Originally Posted by dshreter

Do you measure your pH from runoff to account fir the medium or the fetigation solution? I’m growing in mostly peat which I understand is acidic, so I assume needs to be factored in?

You are not growing in peat moss, but in a mix based on peat moss. The pH of that mix is probably somewhere around 6. You should definitely do at least some runoff measurements to see how off they are. The more runoff, the closer they will be. The pH of the water is not that important, but the carbonate content, that will mostly dictate what direction your rootzone pH will go to.

Also, a stock solution with calcium nitrate should definitely possible, texas tomato food has a good amount of calcium nitrate in it, not sure what the trick is though.

[grassroots159]

AK Mark - How much liquid masterblend, epsom salt, and calcium nitrate mix would you feed a plant in a 10 gal container per day? 1/2 gallon per day too little/too much?

[dshreter]

I'm not AKMark, but you should water to the plant's water requirements. I believe he has recommended that he feeds during almost every watering.

[AKmark]

Originally Posted by grassroots159

AK Mark - How much liquid masterblend, epsom salt, and calcium nitrate mix would you feed a plant in a 10 gal container per day? 1/2 gallon per day too little/too much?

How big is the plant, how warm is the weather, sunny or cloudy, what cultivar, etc, etc? You water when the plants need it. I water three times a day right now, but it has been warm. Use observation to decide frequency, the rest is noted.

[D.J. Wolf]

AK Mark. I did soil tests myself with a Environmental Concepts test kit this spring. According to it, I am N depleted, P sufficient, and K off the chart (I'm I'm reading the K test right) PH at 7-7.5. Other than a dump of AMS (which I did at .5#/100 sq ft.) what would you recommend?

[AKmark]

Originally Posted by D.J. Wolf

AK Mark. I did soil tests myself with a Environmental Concepts test kit this spring. According to it, I am N depleted, P sufficient, and K off the chart (I'm I'm reading the K test right) PH at 7-7.5. Other than a dump of AMS (which I did at .5#/100 sq ft.) what would you recommend?

This is really helpful in your case. When we have to piece stuff together out comes the general use, or we dial back whatever everyone else is using and use observation from there. So we know K is the most important, (for the tomato plant) P is immobile in soil, no N per say, second most important, and you need some secondary nutrients in there.

If it were me, I would add Blood Meal and Fish Bone Meal or Seabird Guano and would still add some K/ Langbenite, which has MgSO4 in it too.

I would also be tempted to use our 4-18-38 mix once a week for another method, and would use observation as a guide for further application.

Last would be a general use or very dialed back whatever and observation again, notes are helpful too.

I tell people often that we stumble forward, that's how we learn the best.

Good luck, tomatoes are hard to burn up, they are also pretty forgiving.

https://nrcca.cals.cornell.edu/nutri...CA2_print.html