when to switch from nitrogen to more potassium

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xwindowuser
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when to switch from nitrogen to more potassium

#1

Post: # 39694Unread post xwindowuser
Fri Jan 29, 2021 7:10 pm

Several have said use nitrogren the first half or start of the seasopn and then more potassium second half or there abouts. when do you make the switch?

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MissS
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Re: when to switch from nitrogen to more potassium

#2

Post: # 39702Unread post MissS
Fri Jan 29, 2021 8:40 pm

I myself use nitrogen for the whole season. In the seedling stage I use nitrogen and phosphorous. Nitrogen for green healthy growth and phosphorous for growing roots and encouraging blossoms. Once fruits have set I change over to nitrogen/potassium. Potassium makes strong stems and encourages fruit growth. So once you start having tomatoes set, then it's time for more potassium in the mix.
~ Patti ~

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Cole_Robbie
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Re: when to switch from nitrogen to more potassium

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Post: # 39705Unread post Cole_Robbie
Fri Jan 29, 2021 9:39 pm

Agreed. I alternate cal nitrate and masterblend 4 18 38, beginning when there are small fruit.

xwindowuser
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Re: when to switch from nitrogen to more potassium

#4

Post: # 39714Unread post xwindowuser
Sat Jan 30, 2021 1:57 am

Cole_Robbie wrote: Fri Jan 29, 2021 9:39 pm Agreed. I alternate cal nitrate and masterblend 4 18 38, beginning when there are small fruit.
So calcium nitrate only at the beginning? and the alternate between Cal Nit and Masterblend when fruit sent?

My concern is making the plants grow too much and getting tall and leggy before setting fruit.

xwindowuser
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Re: when to switch from nitrogen to more potassium

#5

Post: # 39715Unread post xwindowuser
Sat Jan 30, 2021 1:57 am

MissS wrote: Fri Jan 29, 2021 8:40 pm I myself use nitrogen for the whole season. In the seedling stage I use nitrogen and phosphorous. Nitrogen for green healthy growth and phosphorous for growing roots and encouraging blossoms. Once fruits have set I change over to nitrogen/potassium. Potassium makes strong stems and encourages fruit growth. So once you start having tomatoes set, then it's time for more potassium in the mix.

So what is your fertilizers you use?

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MissS
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Re: when to switch from nitrogen to more potassium

#6

Post: # 39744Unread post MissS
Sat Jan 30, 2021 8:45 am

Once the plants are in the ground I use Blood meal for nitrogen, Bone meal for phosphorous or Super Phosphate and Potassium. I will also supplement with quick feed snacks of Urban Farm Apples and Oranges while plants are young and then switch to Texas Tomato Food once flowering begins. I have also been known to forego the Urban Farms and just give them a snack of MiracleGro. I am also a fan of using MycoGro to add mycorrhizal fungi for root growth. There are all kinds of ways to feed your plants so find what mix works best for you. The very BEST way is to start with good soil!!!
~ Patti ~

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Cole_Robbie
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Re: when to switch from nitrogen to more potassium

#7

Post: # 39788Unread post Cole_Robbie
Sat Jan 30, 2021 5:39 pm

xwindowuser wrote: Sat Jan 30, 2021 1:57 am
Cole_Robbie wrote: Fri Jan 29, 2021 9:39 pm Agreed. I alternate cal nitrate and masterblend 4 18 38, beginning when there are small fruit.
So calcium nitrate only at the beginning? and the alternate between Cal Nit and Masterblend when fruit sent?

My concern is making the plants grow too much and getting tall and leggy before setting fruit.
It probably depends on your soil. Over the years I have come to rely more on soil improvement than fertilizer. Everyone's growing conditions vary as to what exactly works best.

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sjamesNorway
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Re: when to switch from nitrogen to more potassium

#8

Post: # 39810Unread post sjamesNorway
Sun Jan 31, 2021 4:26 am

image.png
Here's the best summary I've seen of the plant's needs over the season.

Steve
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mama_lor
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Re: when to switch from nitrogen to more potassium

#9

Post: # 39920Unread post mama_lor
Tue Feb 02, 2021 2:54 am

I would say start with a light fertilization of something balanced, maybe a bit higher in P, and get the higher doses only after fruit set, even for N. Not sure why this is a popular concept, but heavy nitrogen at the beginning is imo the worst idea as the plants are already prone to being too vegetative at that point.

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