I usually grow using a 70/30 coco/perlite blend. This next run, I’m going to change things up a bit, as I’m really starting to get things dialed in. I plan on using build a soils coco mineral kit, to hopefully cut out the calmag I’ve been adding to my RO water. I feed Megacrop which is already high in calcium, so I’m hoping running just Megacrop and RO will be fine with the mineral kit, so I can stop spending money on cal-mag.
My real question though, has anyone had success using biochar in place of perlite? I would use less, seems like 5-10% is the magic number. My main goal is to provide a better home for microbial life (I use Recharge during veg and I alternate between Mammoth P and soil balance pro during flower) without losing the aeration properties of perlite. Look forward to hearing everyone’s experiences.
Possibly run a side by side not sure it can totally replace perlite. But maybe a third less perlite with the rest bio char. Holds water more than perlite.
Are we talking about the same finely powdered biochar? While it may technically hold more water than perlite on some basis, say by volume or by weight, but it does so in way that affects soil structure in an entirely different way. I don’t think an addition of any amount of biochar would replace the need to lighten your soil/media with perlite, pumice, etc. In fact, the superfine nature of biochar increases the need for larger particles such as pumice or perlite in your soil.
Biochar and perlite do very different things and one cannot substitute for the other. Biochar may be a nice addition, but the verdict is still out as far as I’m concerned. Be certain that your biochar is as fully “charged” with microbes as possible before you apply as there have been studies that show that it can be a year or two before you may see any benefit to your soil from biochar as its sorbent properties latch onto and hold many types of nutrients and minerals. That is precisely why it is used in filtration. Perlite on the other hand is used for soil tilth and aeration.
My personal suggestion would be to replace 100% of your perlite with medium to large pumice stone. It breaks down slower, doesn’t float away, and provides a better home for microbes than perlite. Then, experiment with controlled amounts of microbially charged biochar additions if your personal research into it deems it worthy.
I should add that I added about one cubic foot of EM-1 enhanced biochar to the 35 cubic feet of living soil in my current indoor garden soil rotation. I did so after a modest amount of research, but if I knew then what I know now, I’d have probably skipped it. I think that a regular addition of microbes and humic/fulvic acids through use of a product such as Recharge will provide most of the alleged benefits of biochar through PROVEN science not just wishful thinking at this point. I’m still waiting for more conclusive studies before I’ll add any more biochar.
Spend the $30+ on a starter worm bin instead if you don’t already have one, better bang for your buck.
Is there any downsides to using pumice for aeration? I looked into once before, and I thought there was something I didn’t like about it, I may be thinking of hydroton too though. Before the beginning of this grow, I played around with the idea of using something else for aeration. The biochar that build a soil sells looks to be roughly the same consistency of perlite, maybe a little bit bigger chunks. They have it under the aeration category, which is why I thought I could use it in place of perlite.
Yeah perlite and biochar are pretty different and have very different properties when you add them to soil. I wouldn’t try to substitute one for the other.
Instead I would do your regular mix and add biochar at about 5-10% of the total soil volume.
Pumice is great stuff and is actually a better choice than perlite if you are using the soil long term. Pumice is similar to perlite but the chunks are much more durable. This means pumice will last a lot longer, where as perlite crushes and breaks down into dust fairly quickly. You can definitely substitute pumice instead of perlite in most situations, but biochar is a totally different kind of thing with a different texture, so its not a good substitute.
My reasons for wanting to substitute bio bar for the perlite was two-fold. First, to provide somewhere else for micro-organisms to colonize other than the roots, and second, because I multi-feed, and it doesn’t take long for the perlite to all float to the top. Upon reading about Pumice more, it seems it also makes a good home for microbes, would there be much benefit to using both biochar and pumice? I’m thinking of doOmg 70/30 coco/pumice blend and then add in Build-a-soil’s Coco mineral kit and call it good.
how did this end up going?