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Joined: Tue Feb 16, 2016 1:50 pm

Soil Quality

Hi all,

I have been on and off with gardening, but I have been trying to start up again. Any ideas for testing soil quality. Is it worth it to buy a kit. I really don't want to start planing then have everything start dying. I live in Arizona so I don't think the soil is the best.

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Super Green Thumb
Posts: 7447
Joined: Sun Jan 18, 2009 10:20 pm
Location: Northern Utah Zone 5

Perhaps I am weird, but I have been growing things for over 70 years and have never done a soil test. Water and nitrogen are the things most often needed in garden soils. I just assume it will be good to add some nitrogen. Potassium and phosphorous too are often lacking. So I suggest you get something in a bag the supplies NPK and follow guidelines on the bag. .

Greener Thumb
Posts: 1030
Joined: Mon Oct 19, 2015 9:12 pm
Location: central Ohio

I've never done a soil test either. Adding lots of organic matter will help any soil.

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Joined: Tue Jan 01, 2013 8:32 am
Location: Hawaii, zone 12a 587 ft elev.

I have done soil tests. It is a good idea to get a baseline and to get recommendations for what to add and how much fertilizer you need. I had good production before I did the tests but I used 3 packages of miracle grow every two weeks. Everything was lush and green but not a lot of flowers and my root crops made leaves but not roots. It was fine for leaf crops and tomatoes were huge and produced a lot of tomatoes, at least more than I could use.

After I did the soil test, I found out I was over fertilizing a lot. I have done 4 tests so far and only one garden has come down enough to add more than nitrogen. The other two gardens are extreme in phos, potassium and high in calcium so I only need to add small amounts of nitrogen. Saves me a lot of money on fertilizer I don't need. I only use complete fertilizers mostly on potted plants but not in ground.

I do add organic matter. I am actually adding twice as much as I did before. It is still raising the phosphorus level but it is improving the tilth of my clay soil.

I get soil tests every 4 years or so just to check the balance and fine tune the fertilizing. A soil test at the University extension service costs $25 and includes pH, major nutrients, tissue analysis if I send a tissue sample for nitrogen. Nitrogen is not included on the test since it is a volatile element. Recommendations are for general garden vegetables and I get fertilizer recommendations per 100 sq ft. It still helps to have a scale since most of the recommendations are in pounds. It is more accurate than a kit test and kits don't give you fertilizer recommendations.

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Super Green Thumb
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Joined: Mon Mar 23, 2009 1:59 pm
Location: TN. 50 years of gardening experience.

Where do you live in AZ? I lived in west side if valley Phoenix area for a few years. AZ soil is very bad it has little food value for plants. Add lots of organic material and some fertilizer. PH is 8. Add lime for tomatoes and squash.

Corn grows good there but it is all stalks no corn. Tomatoes, squash, beans, broccoli, herbs, sweet potatoes, melons all do good.

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Super Green Thumb
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Joined: Sun Feb 15, 2009 6:04 pm
Location: TN/GA 7b

You can just assume that adding nutrients and organic matter (compost! mulch ! ) will help and can't hurt (as long as you are adding organic stuff not concentrated synthetic chemicals ). But personally I think at a bare minimum you need to know your soil pH. You can buy meters for that . The kind with the long prongs are usually good enough . Just because you are in AZ, your soil may or may not be as alkaline as his was. If it is , you will need to work on correcting it, if you want to grow veggies . Most of them cannot tolerate that level of alkalinity .

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Joined: Tue Feb 16, 2016 1:50 pm

I am in the Tucson area, I essentially have two plots an old garden that produced some tomatoes, jalapenos, and squash that has not been used for some time, and a new plot, the soil is caliche, so I have to add some fertilizer, but I do not want to over fertilizer it. I figured a soil kit would help me determine what I should add.

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