Feeding/using fertilizer on seedlings


That would be cool!!! Would like to see a video of how u do LST…! Thanks @DTOM420

So, U tested and found out that ur FFOF was at 5.5 to 5.7? But u then amended ur soil to bring it up to 6.5? What did u use to do that? Dolomite Lime? Anything else? Worm castings…? I did not test my FFOF before putting it in 2 of my bigger pots, So my soil is going to be whatever my FFOF is approximately, there is a little bit of Gardener’s Gold in those pots too. I did some tests of my soil, straight from the bags, using my water for my plants which I thought was about 6.58 or so, then later it looked more like it was 6.63… Maybe my ph meter is not so good? It is fairly new! FFOF came out around 6.42 or 6.43 ph…, and Gardener’s Gold came out at around 6.63 ph. Not sure how a person is supposed to find out exactly,(or as close as one can get), what ph of a soil is? Maybe use water that is 7.00 ph, I guess? My ph meter seems to keep going down sometimes when I swirl it around, and then hold it still. So, these are the numbers I came out with after the meter stabilized, I think.


Hey @skgrower, You use General Hydro nutes? Right? Do u use Cal/Mag when u r using nutes? Reading the bottles of the General Hydro nutes, seems there might be enough Cal. and Mag. in those? And adding Cal/Mag too, might be too much? Do you only use Cal/Mag. on seedlings then? Sorry, if u already told me, I must have forgot… I think u said u use nothing until plant has 4 or 5 nodes or something??? Thanks!!!


Don’t feed until at least 4 sets of leaves. I use 2ml/gal of ca/mg once a week when I feed. I probably don’t have to because I have well water, but it’s never caused me any problems. I add the Calimagic to the other 3 nutrients along with fulvic acid for stem strength. If you’re using good soil, you shouldn’t have to feed until they’re almost into flower.


I tested my FF soil with a Accurate 8 soil pH meter. They’re about $55 on Amazon, have a long soil probe and read moisture level of soil. They’re not going to be lab-accurate but I think they give you a pretty accurate reading. I have NOT amended my FoxFarm soil specifically for pH but I do add Dolomite Lime and that will help to raise it some. What I DO do is…1) I use my meter to measure the soil my plants are growing in. 2) I modify the pH of my water to compensate for the acidity (or alkalinity, if that were the issue) of the soil. For example: if my soil reads 6.0 (and I want 6.5) I adjust my water to 7.0 so that, hopefully, the combination will produce a 6.5pH environment at the root zone. You can also run a slurry test from the runoff and if it’s off a bit, adjust your water further until you end up with a runoff that’s at your desired pH.

Now, I AM working on some of my (alkaline) native soil - amending it with compost and all sorts of amendments to grow in the ground. For this project I sent a native soil sample off for lab testing. Those results give me an idea of what I need to correct. Once I have added the nutrients I think it needs and testing it along the way with my probe, I’ll send another sample (of the amended result) to the lab for testing. I’ll repeat the process until I get a report back that my soil in the beds is pH’d properly and has all the nutrients it needs.

If your runoff tests at 6.5 you’re golden! Even if it’s 6.6 or 6.7 or 6.3 - anywhere in that range you’re just fine if you’re growing in soil. When you test water pH, always swirl the probe around in the solution before letting it settle and taking a reading once the numbers stabilize. Without movement of the probe you can get a air bubble on the sensor that will throw off your result. You’re doing it just right - keep it up!


@skgrower, @DTOM420…, How often do people feed nutes.? Every watering, every other watering? Is it bad to feed every watering? Or maybe it just does not help? Thanks again for all the help!!!


I feed once a week myself @750 ppm for veg and 1000-1100 ppm after week 3 of flowering. You definitely want to be careful not to overdo it with nutrients or you’ll cause a lockout and have to flush to get the plants back on track.


Thanks again @skgrower!!! Well, I do not understand ppm’s yet… Sorry! Started to read an article on it after u posted this, but think I fell asleep… It was real late! Was looking at the feed chart for Gen. Hydro nutes. U must know the one…? Was trying to figure out what u meant, (as they do say approximate ppm’s, and also exact ml’s per gallon on their chart, they do have a lot of other nutes listed in that chart that I do not have, and I am not sure if those are included in the ppm’s or not though…), how much u use…

I was going by this feed chart I found on some website… They say to use way less than General Hydro says to use, in general… It seems to me… Not sure why that is…

So u must be using about what the Gen. Hydro. feed chart says??? Have u ever looked at that chart? Perhaps a looooong time ago…? U might use a little more than what the Gen Hydro. feed chart says after third week of flower, (as that chart tops out at 900 ppm’s, I think)? Maybe a little extra on the Flora Bloom, after third week of flower…?

Thanks @skgrower!!! I bet ur W.W.'sand other plants are looking great now…?


I use from 1100 to 1300 ppm nutrients once a week on flowering plants. The GH chart is a guide on how many ppms you should measure if you use the amounts recommended. You should buy a TDS (total dissolved solids) meter from Amazon for $12-$20 and you will know what PPM your feeding your plants. You should also be checking the run off ppm after you feed the plants. If it’s higher than the PPM you’re feeding the plant, you have a possible problem that needs to be corrected before it causes damage.
Both pH and PPM are critical to growing good cannabis @heybudletsparty


Wow, Killer looking Crop @skgrower!!! How many plants are those? Is that one W.W. auto in there? Are those all auto’s? I wonder what kinds of lights u use? And which ones u think are the best? I wanna get another light, and a tent, so I can have 2 crops going at once!!! Kinda thinking i might get a light that runs hotter than my Q.B. LED…, and put that in my walk in closet, and blow the hot air into some of the house this winter. Of course, as I am thinking of that, it has been kinda warm around here lately, and I would not be able to just turn off the lights, if I got a crop under it or them… So, might not be the best idea…? lol Might just get another Q.B.? Wondering what u think about lights that grow buds like in ur pic here??? What ever I get, I want it to work really good, like my Q.B. does…, and ur lights sure seem to work really good too!!! lol

Ok, I will try to start checking ppm’s then!!! Seems like ppm’s would be higher on the run off water, in the over flow pan, if one is using FFOF though? Because there are things that show ppm’s in FFOF, I would think? Bat guano…, and stuff like that…? Thanks again for all ur help Amigo!!! U r growing some great looking buds!!!