Garland
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Joined: Sat Mar 17, 2012 8:16 pm
Location: S. New Hampshire

Nutrient adjustment

I've got a problem with nutrients. I've got raised beds in my greenhouse and have been using composted cow manure to help the soil but things have been going downhill. So - I bought one of the Mosser Lee soil testing kits and check each bed - there are eight. That gave me values for the nitrogen, phosphorous, potassium and pH. Then I calculated how much of the organic 5, 3, 4 fertilizer I needed to add to come up to the values recommended by the company. Unfortunately in a typical bed if I bring the nitrogen up to the recommended, phosphorous will be 2.3 times recommended and potassium will be 1.5. My first question is does anyone have any comments about the Mosser Lee soil test kit - good or bad. Secondly, if I adjust to the recommended nitrate level wll either of the two excesses be a problem. And lastly, which of the three is most important for proper vegetable growth?
I grow the usual stuff - everything from tomatoes to strawberries.
I would appreciate any comments or advice.
Farmer at Garland Farm

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rainbowgardener
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Location: TN/GA 7b

"things have been going downhill" What things? What was happening that made you decide to get the soil test kit and decide that your soil was probably lacking something?

You didn't say anything about what your test kit said, but from the rest of it, I gather that it was telling you P and K were all right (or close), but N is deficient? That is hard for me to imagine if you have been adding manure. In the going down hill, were your plants appearing to have some nitrogen deficiency? That is were they tending to be pale and kind of puny, sparsely leafed, etc?

If that is the case, that you really believe that you need to add nitrogen, but the P and K are ok, why not just add the nitrogen, instead of the 3-4-5? Here's a thread where jal_ut mentions using urea, which you can get in bulk and is 42% nitrogen. Other (less potent) organic sources of nitrogen include blood meal, feather meal, cottonseed meal, fish meal, soybean meal.

https://www.helpfulgardener.com/forum/viewtopic.php?p=247033#247033

imafan26
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Location: Hawaii, zone 12a 587 ft elev.

I am not familiar with that kit. I usually get soil tests for my garden and it will give me specific fertilizer recommendations.

For containers, I just use a good commercial potting mix. I have learned it does not pay to reuse it. It is hard to balance it again. Now, as long as the plant in the pot did not have a virus or serious problem, I just dump the soil into my yard or garden; wash the pot with bleach and rinse and start with fresh potting mix. The best potting mixes I have used has been miracle grow (do not get moisture control), potting soil, and Gardener and Bloom planting mix. The worst was Supersoil.

I am lucky, I have access to a soil sterilizer where I volunteer so, I sometimes bring my soil there to be sterilized so I can use it again.

Otherwise I have made my own potting mix 50/50 peat lite and fortified with osmocote. The mix drains well and the osmocote is slow release. I will supplement with additional fertilizer depending on the plant. Heavy feeders like tomatoes, eggplant, beans, peas will get supplemented with additional granular or water soluble fertilizers. Plants like ginger, taro, daikon which are being grown for their roots need a little more nitrogen in the beginning, but I switch to a lower nitrogen and higher phosphorus to promote root growth. I try to use fertilizers with lower numbers like 9-12-12, 14-14-14, 6-4-6 with micronutrients. If all I need is nitrogen I use sulfate of amonia as a side dressing. I have used blood meal as a pre-plant, but I will supplement in the seedling stage with miracle grow, fish emulsion, or wonderlizer high growth. Compost tea (vermicast) to make the plants healthier.

I am not a purist. I believe in being as organic as possible, but I like the results I get with miracle grow and the resiliency that the organics provide.



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