Soil test

[Bruinwar]

Hi all,

This year our new garden plots are located on land that has not been farmed in many decades (never, according to a local). It's sandy loam mineral soil, pH of 5.6. This is located at my community garden site, each plot is 750 sq. ft. These would be my wife & my own plots, I grow tomatoes, my wife grows other stuff, squash, some peppers, beans, flowers, I don't know, not important as tomatoes.

So we got 1500 sq ft. Soil test from Michigan State has a lime recommendation for mineral soils of 92 lb/1000 sq ft. so 138 lbs for our plots. That certainly seems like a LOT of lime to me. I was thinking added two 40-50 lb bags. Thoughts on that?

This would be on top of the 7 yards of compost I've already added. I also plan to add the 2-18 lb bags of TomatoTone before putting my plants in. I've got a large bag of Gardentone (unsure of the size) for my wife's plot also. Maybe we will need more?

Any ideas, thoughts, comments are welcome, thanks.

-joe

[D.J. Wolf]

Did a little looking for you Bruinwar, and according to Baker Lime, it takes 75 pounds per 1000 sq ft to raise your PH 1. A rate of 92 pounds per sq ft would put you in the high 6's by that calculation, 105 pounds should put you right at 7. Personally, I think I'd start a little lower, maybe at the 75 pound rate, and see what it did. You could always add more between rows later in the year if needed.

[Yak54]

If it were my garden plot I would do your suggested two 40lb bags and go from there because I would be trying to get the ph to 6.5 for tomatoes. I didn't see what ph number their recommendation of 92lb per 1000 sq ft would bring it to but I suspect it would be more than 6.5.

[Bruinwar]

Thank you for your replies. Seriously, I did do my own calculations & 93lbs for 1000sqft seemed like a bit much. I just wanted to run it by some more folks & get a second/ third/fourth opinion. The recommendations were for a "vegetable garden" not specifically for tomatoes.

[Gardeneer]

but this is not the right time to add lime. It would take months for
the like to react.
I would use some fast acting Lime not ordinary garden lime.
BTW If you have any. wood ash you can use that. Wood ash has lots of good stuff in it.
It would be like 5 to 10 lbs per 100 sg.ft.Comes out like like recommendation.

[Bruinwar]

Thanks a BUNCH Gardeneer! I should have known this but did not! Fast acting hydrated lime is a must.

[Milan HP]

Hello Bruinwar,
wood ash can have a pH of up to 12! In my opinion it could solve your pH by itself. Now I understand what I did to my tomatoes when I "fertilized" them with it. I thought it was about too much potassium, but I don't think so any more. They didn't like it at all, because I raised the soil pH too high.

I'd like to warn you: use lime or wood ash to your discretion (no matter if fast or slow) and measure your soil pH after each application. The amount suggested looks a bit farfetched to me. At least for tomatoes.
Milan HP (not pH)

[Gardeneer]

One thing about pH.
Most garden plants can thrive in a range of pH, like 5.8 to 7.2. But I have also heard this many years ago that most garden veggies prefer slightly acid soil like pH = 6.8 or 6.9. That is an optimum. In fact every plant has its own optimum. But as gardeners we cannot afford to provide every plant type its optimum. So as long as we stay in the ball park that would be fine.
JUST AN OPINION>

[Whwoz]

Bruinwar, I would suggest caution also. There are at least three methods used by different soil labs around the world and the pH can vary between methods by 1 unit and without knowing which method it can be hard to offer the correct advice. What is said above is good, but at a pH of 5.6 most plants will perform well. Optimum pH for mineral availablity is 6.5, above that some minerals start to lock up, below that others do likewise. Lockup is only gradual close to 6.5, getting stronger the further away you get. Gradual additions are better than massive doses that overshoot the mark. Repeat testing several times ( you may find it useful to get a home test kit) to get an understanding of how your soil responds

[Bruinwar]

Thanks Whoz,

Too late! I added a small bag of fast acting lime. It is supposed to do 1000 sq ft but I spread it over 1600 sq ft. I'm hoping that is starting small. I am hoping for just a small bump. I will do a pH test in June & post the results here.

It was such a small amount I swear I will be surprised if there is any change at all.

-joe

[Whwoz]

Sounds good. Do a search using "mineral availablity pH" and you should come up with a table showing how each minerals availablity varies with pH.

[Whwoz]

You may also want to do a search for Mulder's chart, a chart showing how minerals interact with each other in the ground

[Milan HP]

Hello Bruinwar,
I don't really think you've raised the soil pH by much. My tip is to 6.0 max (more likely less than that). No harm to any plants.

Milan HP