hey everyone, I'm about to mix up a new batch of no till soil and I have some questions. I am about to switch from growing in a 3x3 bed to using 25 gallon pots. I am allowed 15 plants, so I am going to mix up a ton of soil, about 50 cubic feet. I plan to reuse what I already have. It is a no till mix that has been through 1.5 cycles about 6+ months. It's had worms tiling through it the entire time, so this 9ish cubic feet is going to be apart of my "humus" portion. The mix will be as followed; 20 cuft coco 15 cuft lava rock 15 cuft humus (current mix+ 6cuft fresh EWC) 5cuft Biochar For amendments I'll be using per cubic foot; 1c Kelp meal 1/2c Neem meal and/ or Karanja 1/2c crab meal 1c Oyster shell flour 1c glacial rock dust 1c gypsum 1c Basalt Lots of malted barley powder. Small amount of green sand A couple questions; how many cups of the amendment product should I expect to get out of a lb of material? Say I buy a 25lb sack of kelp meal, should I expect around 75 cups worth? Also, any benefits to adding sawdust in the mix, if so any particular kinds and how much? Anything else worth adding? And finally, anyone in the Seattle area have recommendations to where to buy this stuff? I bought most on Amazon for the last mix and it was a bit pricey, I'm trying to save money. I am getting biochar, lava, and EWC locally. Thank you everyone!!
There are fairly active "no-till" pages, one of which has a link to a soil calculator (first one I link). I started the calculator and someone else modified it a bit and was talking about adding weight to volumes conversion. You might check it out and post this there. All Organic Recipes and Notes Compilation No-Till Gardening: Revisited
I use neem, kelp, crab and oyster at 1/2 cup per c.f. 1- 50lb sack of each amendment is enough for approximately 1500-1800 gallons of soil. A 50lb sack of glacial rock dust will amend 450 gallons of soil at around 1cup per c.f. I would replace the Coco w peat moss. I would also treat your "old" soil as soil and not humus. Sawdust in your soil mix would be a giant mistake. It will rob the soil of N. HTH RD
Thanks for the advice! I have checked out the calculator in the past, I did not think it gave any info regarding how to translate the amount of cups required to how many pounds to buy. I will be sure to go through the threads again. Can anyone with experience using coco in no till chime in? I used peat in my last mix. Peat is great, but compacts overtime and coco has some perks that peat does not. I figured a mix of my peat soil and coco would be good diversity. The reason I thought I'd use my current mix as the "humus" portion is because it has been regularly top dressed, worms have tilled through it for 6+ months, and I've only made it through 1.5 full cycles so I know it still has a ton of nutrients available. I figured it would be to hot to use as my soil portion with the addition of a different humus portion. Thanks for the tip on sawdust. Has anyone tried charging sawdust before similar to charging biochar? I'm not really interested in adding sawdust, but I saw it listed on a couple of soil building websites and got curious.
6 months in the world of no till....is fresh soil. After a couple years it may be used as humus, but even then it needs to be adjusted for the aeration materials in it. Speaking of which, if your old soil was made using the 1/3 peat, lava, compost base, you will end up with 23 c.f. of aeration (include the char) out of 55 c.f. 1/4-1/3 aeration is plenty. I have used Coco in the past. Never above 20% of the mix. It's more expensive. It's less sustainable. It has less CEC. I have a no till bed that is almost 4 yrs old w only 25% aeration (lava and pea gravel). If it's compacted because of the 50% peat moss I used back then... somebody better tell my plants and the worms too. One way I've gotten myself into trouble when I started growing was to completely stray from what I knew already worked. I had to learn the hard way that it's great to experiment, but it should be tested on a plant or two first. Kinda like ...not putting all your eggs in the same basket. HTH RD
Since the current soil is fairly new, should I adjust the amount of amendments added, or use less compost and more peat/coco? The current mix is about 1/3 vermiculite, so I will take that into account when calculating how much aeration to add. Perhaps I'll ditch most of the coco and just add small amount to see how it goes. I can get it fairly cheap, almost as cheap as peat. Have you noticed much breakdown in the peat over the years? I have not ran a mix long enough to encounter the problem myself. Hopefully by next year I will have enough fresh leaf mold and home made EWC to utilize, but having moved twice in the past two years has made it difficult. My worm bin has been up since January but they've taken the back seat on my list of projects, they don't get enough attention and progress is slow!
I tend to stick with less is more thinking. I wouldn't amend the old soil much or at all. After a couple years your no till will look like VC and lava rock when you transplant. I was really into worms and even sold them for a brief time. That said, I don't use VC in my no till beds anymore. I prefer to use compost and allow the worms living in the bed to turn it into VC. This will slowdown how quickly the worms will work the bed. Without doing this I've gotten 4 years out of my soil, which isn't too shabby. RD
I like your thinking. In my first mix I used Oly Mountain fish compost. I get it locally and fresh, not bagged. Perhaps I'll ditch the worm castings in the fresh mix, It doesn't really make sense to have worms trying to break down worm castings. I do top dress with worm castings I make at home, but so far have only produced about 15 gallons. My primary use for them is going to be teas. Thanks again for all the advice, hopefully I'll get to mix this up in the near future. I start moving tomorrow and had to take a break from growing, but I'll be back