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TheWaterbug
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Till in steer manure before planting sweet potatoes?

We just had a week of 80F+ weather here in Southern California, so I'm starting to think about growing sweet potatoes again. Especially since I have my new rototiller!!!!

I have a store-bought sweet potato growing slips in my kitchen, and I'm hoping they'll be big enough to plant in a week or two:

Image

As I prep a bed for them, should I amend with composted steer manure, or no? I read that sweet potatoes want fertile soil, but not too high in nitrogen, else I'll get all leaves and no tubers. But they specifically warn against chicken manure, not steer manure.

Is this bagged stuff considered a "high nitrogen" fertilizer? It's not pure manure; it's a mix of aged steer manure and compost.

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TheWaterbug
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Does no one know the answer to this? Think of the children!!!!1

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applestar
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I don’t really know the answer so I was hoping someone else would answer ... but just to push around some ideas .... since it’s bagged, it must have N-P-K analysis on it? Around here, Composted *cow* manures usually list something like 0.1:0.1:0.1 or some such numbers— very low in everything. Not sure if composted *steer* manure would be different.

I view them as good amendment but not so much fertilizer....

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Gary350
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I have grown sweet potatoes for many years they are a zero maintenance crop. Plants love very hot blistering 100 degree heat in full sun 15 hours all day. The hotter and dryer it gets the better plants grow. Sweet potatoes are like blackberries and okra, try as you might to give plants fertilizer, water, anything other plants like sweet potatoes just don't care. Only thing sweet potatoes don't like is too much water plants will die like a cactus that gets too much water. Very hard clay soil restricts the tubers from growing large. Fertile soil does nothing different than sandy soil it is softer than clay tubers will grow very large. I love to grow sweet potatoes only for the challenge to see how many pounds of potatoes I can get from 1 plant it was 33 lbs about 15 years ago. I don't like to eat sweet potatoes I use to grow them for fun. Plants grow long vines that get about 25 ft long I use a leaf rake to rake vines in a 8' diameter circle around the mother plant once a week. Every place vines touch the soil they will grow roots then grow satellite potatoes each place that vines root. Each place vines grow roots supplies more water to the mother plant. I like to shovel soil to cover up vines about every 16" to help vines grow more roots. Plants will grow until frost kills them. First frost in TN is about Nov 7. I usually have sweet potatoes planted by first week of May. Keep vines rakes up in a tight circle potato leave shade our grass and weeds. Mother plant always has 2 times more potatoes than all the satellite potatoes combined. If mother plant produces 18 lbs of potatoes expect satellite potatoes to be about 9 lbs. If you do absolutely nothing but rake vines in a circle once a week you might get a few satellite potatoes but most potatoes will come from the mother plant 10 to 12 lbs. 10 plants will produce 100 lbs of new potatoes if you do nothing and 3 plants will produce 100 lbs of new potatoes if you work at it. When planting several plants put them no closer than 1 ft apart in a group so you can rake vines in a circle around the whole group.

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TheWaterbug
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applestar wrote:
Thu Apr 30, 2020 8:01 pm
I don’t really know the answer so I was hoping someone else would answer ... but just to push around some ideas .... since it’s bagged, it must have N-P-K analysis on it? Around here, Composted *cow* manures usually list something like 0.1:0.1:0.1 or some such numbers— very low in everything. Not sure if composted *steer* manure would be different.

I view them as good amendment but not so much fertilizer....
If you read wayyyy down on the link above, Kellogg's actually answers the question with, "Steer manure does not have a guaranteed analysis which provides the NPK." :x

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TheWaterbug
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Gary350 wrote:
Thu Apr 30, 2020 8:53 pm
Sweet potatoes are like blackberries and okra, try as you might to give plants fertilizer, water, anything other plants like sweet potatoes just don't care. Only thing sweet potatoes don't like is too much water plants will die like a cactus that gets too much water. Very hard clay soil restricts the tubers from growing large. Fertile soil does nothing different than sandy soil it is softer than clay tubers will grow very large.
So it sounds like your vote is, "It doesn't matter!" at least as far as the nitrogen content goes.

My soil is generally very clay-heavy, but this particular section is actually pretty sandy, so I think I can do without the amendment if the extra nitrogen would be bad..

Decisions, decisions. . . .

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Gary350
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All plants need nitrogen it would hurt nothing to add fertilizer to your soil, it would be better to have it and not need it than to need it and not have it. I grow sweet potatoes in TN but did not grow them in AZ when I lived there. AZ soil has almost no food value for plants I had to add fertilizer & calcium to AZ soil to grow vegetables. One year I bought 1 ton of construction sand to grow potatoes in TN crop size was much larger. Fertilizer in TN makes most garden plants grow much better but does nothing for sweet potatoes. I assume TN soil has enough of what sweet potatoes need adding more it not helpful. Without testing your soil it is had to know if soil it good for sweet potatoes. You could plant 2 sweet potato plants 3 ft apart then give 1 plant, fertilizer, calcium, sand, etc, see if it does better than the other plant that gets nothing. Next year you will know what works best in your soil. Add $1 worth of fertilizer it won't hurt anything it could be better than nothing. $1 worth of fertilizer is much cheaper than a $40 soil test.



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