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Hydroponic nutrients for tomatoes

Posted by vialsoflight 4/5 (My Page) on
Mon, Feb 10, 14 at 8:49


I'm new to this forum and new to hydroponic gardening in general. I started doing it this year as a way to beat the winter depression I often get by January, and I must say, it's better than Prozac. I have had amazing success right out of the gate.

However, I have one question that I haven't found an answer to anywhere on the web, and it's regarding the high TDS recommendations for tomatoes. I have 2 tomato plants growing separately from my lettuces. One in a drip system and one in an ebb and flow system. I follow the directions on the bottle of Grow Big which seems to be perfect for my greens, but the TDS meter never gets above 800, which I know is way too low for my tomatoes . I do also add Cal/Mag to the tomatoes, but still it doesn't seem to get high enough. I made the mistake of doubling the amount of Grow Big which brought up the TDS reading, but the tomatoes looked like they were starting to burn, so I dumped the water and started over according to the original directions.

My question is how do I safely add enough nutrient to my tomatoes over and above the Grow Big and Cal/Mag without killing them, but giving them enough so that they will give abundant fruit. The directions on the bottle seem like a once size fits all, but I am realizing that all veggies have different requirements. Thanks for any advice you have. So far the tomatoes are doing great, but growing very slowly and are only producing a couple of flowers. They are 8 weeks old this week.

Follow-Up Postings:

RE: Hydroponic nutrients for tomatoes

Fox Farm says to switch to their Tiger Bloom or Big Bloom when flowering starts. Grow big is 3-2-6, which is too much nitrogen to feed mature tomato plants. You'll end up with more vine than fruit if the N is too high.

The middle number, phosphorous, is typically identified as being the bloom maker. But especially with tomatoes, I think the potassium is just as, if not more important. The fertilizer I feed my garden tomatoes in soil while they are fruiting is 4-18-38.

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