Hey growmies! I’m on my first autoflower grow and I was wondering when I should feed my girl. She is around 11 days old and looks healthy! I’ve ordered a small pack of a jacks 3-2-1 bundle and I’d like to know how many of you guys feed, etc. I’ll probably start by mixing in the gallon and then do regular amount water but with the feed instead? Here’s some pics of my auto!
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What medium are you growing in? Amended soils from companies like Fox Farm will feed your plants for roughly 6 weeks with water only. You’ll need a TDS pen to test run off and know when and how much to feed as well as a PH pen to adjust the nutrient mix and test the run off 
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@OGIncognito has got you covered. I would have asked the same thing.
I will mention that the little meters would better serve your needs placed about a foot above your plant. The humidity it reads setting on the wet soil will give you a totally false reading for the tent conditions.
I have mine about midway up the tent side out of the strong direct light.
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Appreciate it! I’m growing in around 70% FFOF, 15% perlite and 15% coco coir. Less perlite because I didn’t realize FFOF already had some in. Got a link to a good TDS meter? I’ve been meaning to purchase one. I also have Bergmans fertilizer and not sure but I’ve heard jacks 321 is really good.
I also already have a PH pen and just purchased the up/down for the water / nutrients.
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Appreciate it! Honestly wasn’t using it for any actual “reading” as I have a probe doing the readings for me. It was kinda there just to be there. I bought a pack of 8 or so and they came already on, should probably remove it and save the batteries.
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Right on, I have and like my Blue Lab TDS pen. Do you know your tap or water source PH? Jacks 321 is great, simple, clean and inexpensive nutrients from start to finish
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Yeah actually I do. It’s funny honestly because the filtered water we use is lower than our tap, usually reads from like 6.4 - 6.9 and our tap is more on the higher side at around 7.0-7.5. I’ll have to do more tests to get accurate with it though.
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OG is right, Jack’s is badaxx. My tap pH is about 7.7. When I mix Jack’s, whether it is normal ratios or adjusted, the pH falls between 6.43-6.53. No joke, unless I add other nutrients or boosters, then I don’t even get the meter out. It only drifts up by about .05 a day so 5 gallons lasts me a few days with no adjusting. Also, Apera and BlueLab makes great meters. That’s my experience with Jack’s. I started with FF liquid and powdered nutes. Too much mixing and ph’ing and doesn’t last nearly as long as Jack’s does.
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Thanks! I’m gonna give it a try, when do you think I should be giving nutes to her?
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I have lots of them . I put them in the jars with the dried buds to monitor the RH.
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If its filtered below 100 pmms the readings may not be accurate.
It takes a special expensive meter to read pH in things like distilled or Reverse Osmosis water.
If its ppms are 150 or better than its probably right.
When you get a TDS pen this chart will help
I think pretty much any TDS pen will do the job. Some are faster than others.
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@Sammys , FFOF is relatively hot and should last a minimum of 4+ weeks. I started Jacks (light doses) after 3 weeks growing in FF CocoLoco which is not as hot. It’s good to get a TDS meter so when the ppm number goes down into the 700 neighborhood you can start feeding to get the ppm up over 800-1000 and gradually higher.
Jacks is great and JR Peters will give you recommendations to adjust the formula according to a water sample you can send them.
I see! So I shouldn’t feed until around 3-4 weeks old? I also just purchased a TDS meter, should be here tomorrow. Also please tell me more about the water sample? What’s that for?
So since I’m using FFOF, my PPM should be around 400-500 ppm?
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Yes runoff.
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I don’t know how consistent they are with the OF. I’m running a bit high ppm cause I use my well water and collected rain water blended. So I’m starting with 200ppm plus feed and pH down and molasses it all adds up.
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There number is on the bag of feed they’ll help.
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So I’m measuring the PPM of my runoff? What do I do after I measure it, let’s say it’s 100 over or whatnot. Or if it’s perfect? What does it mean for me to do in general.
The TDS in runoff gives an indication of how much nutrients are in the soil. Once the plant gets healthy in veg. You can go up to 1000 and higher. By flower time even +1500 ppm.
You can also measure your ppm after adding ferts, Jacks has charts on their web site.
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