Reusing Soil Experiment

Hi Friends!

So after 2 outdoor grows with Roots Organic 707 I have heaps of pots with perfectly good soil that I hope just needs a little love to re-purpose. I’m also trying my first indoor grow so this is not a controlled scientific study. So after geeking out a lot on the internet about living soil and all the good stuff folks use to build a healthy base outdoors for my indoor grow. So…I’m trying this lol. Please know I might kill everything and it might not be the soil, but if you can re-use your soil and get good results, it may be a worthy endeavor. That said, I’m not good at moderation and like to piddle.

Here’s what I did: removed the big roots as best possible since they don’t have a chance to completely break down. I’m using (5) 1/2 gallon pots so 2 1/2 gallons of soil. Did a flush with Clearex first to get my PPM’s down. Added some Sensizym to cleanse the roots so my great white microenzie stuff would live. My PH is after this was 6.5 in and 6.3 out. Added 2 tablespoons of dolomite lime, and 15% of organic worm castings.

This is what my bag seeds (Gelato from a friend) look like now sprouted 2 weeks ago and just transplanted today. I guess if they somehow survive and thrive, in spite of all the new variables, there may something to this. BTW I only use RO water so no chloride/chloramines are in play to wipe out all the goodies in the soil.



Outdoor grow… no problem… indoor grow and your just asking for problems… :wink:
just my opinion… :wink:
Although… I must say that you did a good job at trying to reuse the soil… I just dont think it’s a good idea… :wink:


Hi @peachfuzz !!!

I read your posts and all the other good folks who know much more than I do and have nothing but respect for your sage advice…but I come from a long line of piddlers :sunglasses::sunglasses::sunglasses:

No worries my friend… I’ve grown for years in soil… but the last 3 have been in dwc in the beginning with baskets and clay balls… but 1 1/2 of the last years have been just water and neoprene collars in a DIY rdwc system… no medie… way cheaper and no bugs… never going back to soil… unless back outdoors… but I have a hybrid dwc/soil system that I use for outdoors… :wink:


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I have a lot learn @peachfuzz :star_struck:

So I just gave the topsoil a good dusting of food grade DE so any critters that might incubate will have a tough go of it. I’m just having a blast doing this :sunglasses:

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Can tag you to my thread if you want… lots of good info… scroll to the top to see how things progress… :wink:
Up to you… :grin:


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Please do…I have a hard time keeping up with all of this! Back to making chicken fried steak and baked taters for dinner :zipper_mouth_face:

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I’m interested how this goes. I have reused Roots Organics soil for two grows. I stopped at the second because it was outdoor and I had issues with mites and aphids. When I use it for the first time now, I don’t nute for a few weeks, but with the reused stuff I nute right away. When I nute I typically go 1/4 dosage too.


Hi @Sixpackdad!

I’ve been watching your thread and you’re killing it bro! You remind me of me…I think that’s a good thing but wifey may say otherwise :sunglasses::sunglasses:

I used the botanicare nutes for my 2 outdoor grows and have heaps so I’m going to use it indoors. Had a minor go with thrips briefly but spinosad quickly sorted that out. My issues were the dreaded looper moth spawn and then bud rot right before harvest last season. Got 3 lbs of buds but lost at least another 5 but it’s all good. So the soil didn’t have pest issues. I also start well below the recommended feeding schedule and watch how the girls respond. For my indoor grow, I had to flush with Clearex because I tried a new method on the last outdoor grow and didn’t flush, but rather tapered the nutes down at the end, based on some stuff I found on this forum. I like to try new stuff lol.

How much fun is this eh? Cheers!!!


I am in NY all week and the wife is managing the girls. She is sick of sending me pics so I know they are ok. Can’t wait to be home.

Hi All! It’s been 9 days now after the transplant into the 4x4’s with the repurposed soil. Added a top dressing of food grade DE and no sign of bugs so far as I can tell. They seem to be doing their thing and I’m trying hard to not over love them. No watering has been needed since they were transplanted so no PH runoff results yet. Probably in a few days they will get a small amount of cal mag and liquid karma when watered. The temps are set for 67 at lights out and 76 during lights on with a 3 degree variation using the inkbird as a controller. My little oil heater / pc fan combo seem to working nicely and the temps slowly change like if outside. Here’s a pic of that combo just outside the tented bathtub.

A shot of the girls (hopefully) from above. There appears to be some light burn on the lower leafs on the far left. My QB 260 V2’s are set to 112 watts at 30" below. My plan was to raise this gently maybe 10 watts every 3-4 days to slowly harden them. Will play that by ear based on their response.

Here’s a side view.

Something strange is going on with the far right plant. There is no apparent new growth on the main stalk and it’s purple. There is a tiny new shoot just above the first leaf after the cotyledons. I’m curious what’s going on here.

So I haven’t managed to kill anything yet :sunglasses::sunglasses::sunglasses:

Cheers and Happy Holidays!


I have been reusing my soil in doors it works but way more issues then if I use new they will grow after all it’s a weed


I’ve never had the weird plant thing happen to me, but I’ve seen it once or twice on other posts. It’s like the plant decided to abandon on its main shoot and start another.

Plants look great. Congrats!

I am too cheap to not reuse my soil. It can get hard and not hold water as well. I soak it first with some SM90 soil conditioner and it retains that spongy feel Then a dose of light nutes and Terpinator

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What kind of issues do you experience? At 16-20 bucks per 1.5 cu ft I have to reuse. I’ve reused for one grow, with the only change was I was more aggressive with nutes early in the grow. My plants were great until mites and aphids (it was an outside to inside grow) had there way, which I why I threw out that soil and started fresh in my current grows.

Hi All!

Here’s my weekly update. They got their first watering after the transplant 2 days ago. Took 16 days to dry out. Used 50% of the recommended botanicare nutes including cal mag plus, liquid karma, silica blast, and the grow formula. Keeping a close eye on any sign of critter activity. So far nothing but it’s a concern. They are starting to take off now. I still have the QB 260’s at 112 watts 30" above the canopy. They aren’t stretching and seem happy, but I need to harden them further at higher light intensities so am going to increase in 10 watt increments every 4 days or so and see what happens. In the next 10 days or so they will get transplanted into 3 gallon fabric pots including the WOW Mycorrhizal Inoculant I just added to my regimen. Used some Great White already, but wanted to see what this does (I like to piddle with stuff lol).

Here’s a shot from the top

Side shot

And Stubby. I need to cull this one but don’t have the heart to do it just yet.

Thanks again for all your help!!!



Going to try re-using some soil also. Bf has done an ultra finstift as of right now. Good luck look forward to following

Hi All,

Transplanted the girls into 3 gallon fabric pots yesterday and dropped them into the tub. Insulated the bottoms of the water trays so the roots stay cozy and aren’t in direct contact with the porcelain. They were getting a bit droopy and while not super root bound, it was time. The QB 260’s are now at 30" and 132 watts. Still raising it 10 watts every 4 days or so. No sign of bugs, so keeping my fingers crossed. Stubby had to stay in the 4x4 due to limited space. I will likely cull her at some point but she’s hanging in there. The one new shoot is taking off…she’s a gamer.

Will top for the first time in a few days once they get acclimated to the new pots.

I miscalculated the amount of soil needed so used an organic mix I made last spring for my tomatoes for the girl on the far left. It’s a veg recipe but needed to get them transplanted. We’ll see how that works out.

Haven’t killed em yet!!!



Just ran across this…

I reuse my indoor soil every time. In place, in fact. I give it a top dressing of kelp, neem meal, malted barley ground to a powder, crab meal, maybe some pelletized gypsum… add a layer of high quality compost (an inch or two), throw down some cover crop seeds, add a thin mulch layer and go at it again.

To reuse it in place, you need at least a 15 gallon smart pot, but if you’re willing to dump it out and re-amend it every cycle, you can get away with much smaller pots.

High quality soil leads to high quality soil life - which will (in addition to solid IPM practices) suppress the troublesome soil life.

EDIT: My style won’t work with any “nutrient” lines. All that will do is kill your soil life and leave you open to pest advances. Best of luck.


Hi @BlackShirt

That’s my goal is to ultimately go with an all organic self-sustaining soil. I still use botanicare nutes. Re-amending the soil is not a problem. Just need to learn how to do it with repeatable good results.

Thanks for your response!!!