Sadeghsep
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Posts: 2
Joined: Tue Jul 21, 2020 6:45 am

Preparing nutrients solution help

Hi
I'm new to preparing my nutrient solution , I used to use A and B from the market which I found they are not so great so I tried to buy these 3 as I attached pictures
1.Hydroponic nutrient 9-9-43
2.Magnesium nitrate
3.Calcium nitrate
I tried to prepare my solution as the scale of 2 of number 1 and 1 of each 2 and 3
I tried to set EC on 1.6 for lettuce and 1.5 for strawberries
Strawberries seems stable but a few less noticable white dots on the leafs but they are doing ok
Lettuces are growing so fast and leggy also my the pH is going down as I set on 6.0 now after almost 7 days it's 4.9 I think it means I give some nutrients much
I can use some help , thanks
Attachments
IMG_20200711_102841759_HDR.jpg
IMG_20200711_102813132.jpg
IMG_20200711_102721114.jpg

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Gary350
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Joined: Mon Mar 23, 2009 1:59 pm
Location: TN. 50 years of gardening experience.

Each plant has a nutrient it needs.

Online search for strawberries says, equal amounts of NPK fertilizer can be 5-5-5 or 10-10-10 or 15-15-15 or 20-20-20.

Online search says, lettuce does best with equal amounts of NPK.

Look for fertilizer with equal NPK if you can not buy it then you might need to mix 2 or 3 fertilizers together to get equal NPK.

Knowing how much fertilizer to put on each plant is tricky you should start with low value 5-5-5 fertilizer so you don't over dose plants until you learn how much fertilizer they need. Then you can use stranger fertilizer.

Leggy plants usually mean they need more sunlight but can also mean plants need more fertilizer.

Add calcium to get your ph up to 6.0. Read online to learn what ph lettuce and strawberries need.

Too much nitrogen is not good for some plants and not enough nitrogen is not good either.

Too much potassium is not usually a problem for most plants it promotes blossoms and more fruit and larger fruit.

Mix garden soil with water then use water only to water your plants this will give plants trace elements they can not get from factory made fertilizers.

Sadeghsep
Newly Registered
Posts: 2
Joined: Tue Jul 21, 2020 6:45 am

Thanks for replying
I have too many 9-9-43 I have to figure it out how to use them
I'm just wondering why the pH is going down instead of going up as usual
, Is it the scale of calcium nitrate or magnesium nitrate that I'm mixing

goatherd
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Posts: 1
Joined: Mon Feb 22, 2021 11:18 pm

I'm also blundering my way through my own mixes, so I can't answer all your issues (in fact if you find out why your mix keeps changing it's own PH let me know LOL I've seen it go stubbornly both ways now).

Your lettuces ... leggy would suggest too much nitrogen. Scale back for them, your additional sources of N, namely give less of the Cal-nite and Mag-nite. EC might be a little high too I've heard 1.2?

What do you mean by "white dots" on your strawberry leaves? Do you have powdery mildew?

Strawberries are not my strong point, But what I can comment on your nutrient ratio after Gary's input ...

You are starting with a fertiliser mix inherently low in Phosphorous, which is P, the central figure of your NPK ratings.

To meet an equal ratio of N-P-K, you'll need an additional source of Phosphorous you don't have yet.

Your Calcium Nitrate provides "N" Nitrogen, along with calcium.
Your Mag nitrate also provides "N" Nitrogen, along with magnesium.
At the rate you are feeding Parts B + C, you are proportionally a little too low on N still for this crop .... you are feeding at ratios around N(35):P(9):K(43).

The proportion of Mg to Ca as you are doing it is quite reasonable at Ca19/Mg9.4 (as I understand about twice as much Ca as Mg is good, an expert may correct me) but you need to either use a little more of both Cal-Nite and Mag-nite, or use a little less hydro nuterient part A which is where your high Potassium (K) rating is coming from.

You still have a shortage of Phosphorous (P) which is vital for flowering and fruiting.
You need to find a source of Phosphorous which does not also add too much of another nutrient ... eg, not MKP (mono-potassium phosphate) because that has more potassium than phosphate and will only add to your K problem ...

Phosphorous sources are not my strong point. I mostly rely on MKP.

Your fertiliser mix - Probably a general purpose mix? designed for mostly green crops, you really need more phosphorous for fruiting of any form.

The mix I'm using may be interesting for comparison. It is a 3-part structured to be adjustable to green or fruiting crops. The figures are for a liquid concentrate not a solid so they are weaker than yours but watch the ratios.

Part A (1:3:6) has all the micros, the magnesium, a little MKP, and potassium nitrate. This is used at 10-30ml per 10 litre of water. It is the base for all types of crop.

Part B (3.5:0:0) is just calcium nitrate, also added at 10-30ml per 10l. A light or young green crop will want little: a big green crop will want lots, fruiting crops somewhere in between.

Part C (0:5:6) is just Mono Potassium Phosphate (MKP), and you don't add any for green crops like lettuce. However if you have fruiting crops they want more P:K, like tomatoes, strawberries or in my case buttercup squash, then you add 1-20ml per 10l.

You will note that as the ratio of K is higher than P in both part A and C I still cannot reach an equal 5:5:5 type ratio as Gary suggests for your strawberries.

But, it's a lot closer and the phosphorous is independant of the main Part A mix with micros, so it can at least be adjusted.

Sorry I can't help more but I'm feeling like the blind leading the blind as it is ... You should see the manganese deficiency I've got! :roll:



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