Tuesday, July 08, 2008
Just call me the Coco Nut!
So I had this problem in my garden for what seems like forever : how to give my plants more root space without using huge amounts of very heavy media (such as Hydroton or diatomite rocks, which also need to be washed and cleaned of roots between crops, major hassle) or using more rockwool (expensive, hard to dispose of). The basic rule of thumb is, the larger the plant, the larger the container should be. Roughly this translates to one gallon of container space for each foot of plant height. So for example, if your plant is two feet high, it should be in a two-gallon container. For many years I’ve been growing in rockwool Hugos (the six-inch cubes) but I’ve found that the larger plants, i.e. those taller than two feet when put into flowering, tend to outgrow the Hugos quickly over the usual eight-week flowering cycle and suffer reduced yields as a result of becoming root-bound. I also have limited vertical space in my flowering room (the ceilings are a bit low, about seven feet) so I need to think of the height factor constantly.
I’d tried coco blocks years ago when they first came out, with poor results. It seemed like this fibrous material had to have a constant drip going, and I wasn’t looking for that extra hassle. So when Boss Daddy Jordan at the shop recommended three-gallon containers with loose coco coir, I was kinda skeptical. Using trays sitting above a reservoir, I already lose about two feet of vertical room, so the tall-ish buckets in this tray wouldn’t leave enough room for the larger plants I was hoping to grow.
What to do??
“Run-to-waste, Glasshoppa, run-to-waste,” Wiseman Jordan intoned. Heck, with my injured foot (long story) I can barely walk, much less run. What was this Guru of Growing on about, and why did I have to run there anyway?
Doing a little research on growing in coco coir soon gave me the answer. Basically, coco is the perfect medium for hydroponic growing – light, pH neutral, and able to hold lots of oxygen and water. All of these qualities makes for very healthy and happy roots, which as we know, leads to heavy yields. However, coco is most suited to a "runoff" system, where the nutrient solution is allowed to run to waste rather than the usual method of recirculating from a reservoir (this is also the method used by big commercial greenhouses as well). Run-to-waste helps avoid the possibility of salt buildup in the coco, and flushes unnecessary salts out of the media. Since not all plants use similar amounts of nutrient, and they also secrete salts, any surplus of nutrient makes the coco brackish and changes the pH. By drainage you flush the media every time you give nutrient, which prevents it from becoming brackish.
So, since I wasn’t gonna need the reservoir underneath the tray to catch runoff anymore, I decided to join the three gallon buckets together using ½ inch tubing to form a linked system, with a “drain bucket” with a pump to eliminate the runoff and an external reservoir for the feed, all of which simply sits on the floor. Voila! I just gained two feet of extra vertical space, woohoo! Plus I wouldn’t have to worry about solution in a reservoir building up yuckiness over each week as everything would simply run down the drain rather than recirculate. Cool!
Into the buckets I dropped the appropriate-sized mesh pots (the two-gallon size, I believe), then five-gallon size paint strainers to keep the coco from eroding away into the runoff solution and to allow the roots to grow down into the buckets if they wanted. I filled each mesh pot with a mix of Canna coco (three parts) and chunky perlite (one part) for a little more aeration, just to be sure. Before transplanting, I flushed the buckets with RO water adjusted to pH 5.8, then a weak (300ppm) bloom cycle nutrient solution to “prime” the media and flush out any small particles. Since the initial crop was still in Hugos, I simply placed the big cubes with the plants on top of each mesh pot, to allow the roots to grow down into the bucket. For the next crop I’ll be eliminating the Hugos entirely, transplanting directly into the coco from smaller pots.
So how’d it work out? Stay tuned for the next exciting entry in my coco-nut saga!
I’d tried coco blocks years ago when they first came out, with poor results. It seemed like this fibrous material had to have a constant drip going, and I wasn’t looking for that extra hassle. So when Boss Daddy Jordan at the shop recommended three-gallon containers with loose coco coir, I was kinda skeptical. Using trays sitting above a reservoir, I already lose about two feet of vertical room, so the tall-ish buckets in this tray wouldn’t leave enough room for the larger plants I was hoping to grow.
What to do??
“Run-to-waste, Glasshoppa, run-to-waste,” Wiseman Jordan intoned. Heck, with my injured foot (long story) I can barely walk, much less run. What was this Guru of Growing on about, and why did I have to run there anyway?
Doing a little research on growing in coco coir soon gave me the answer. Basically, coco is the perfect medium for hydroponic growing – light, pH neutral, and able to hold lots of oxygen and water. All of these qualities makes for very healthy and happy roots, which as we know, leads to heavy yields. However, coco is most suited to a "runoff" system, where the nutrient solution is allowed to run to waste rather than the usual method of recirculating from a reservoir (this is also the method used by big commercial greenhouses as well). Run-to-waste helps avoid the possibility of salt buildup in the coco, and flushes unnecessary salts out of the media. Since not all plants use similar amounts of nutrient, and they also secrete salts, any surplus of nutrient makes the coco brackish and changes the pH. By drainage you flush the media every time you give nutrient, which prevents it from becoming brackish.
So, since I wasn’t gonna need the reservoir underneath the tray to catch runoff anymore, I decided to join the three gallon buckets together using ½ inch tubing to form a linked system, with a “drain bucket” with a pump to eliminate the runoff and an external reservoir for the feed, all of which simply sits on the floor. Voila! I just gained two feet of extra vertical space, woohoo! Plus I wouldn’t have to worry about solution in a reservoir building up yuckiness over each week as everything would simply run down the drain rather than recirculate. Cool!
Into the buckets I dropped the appropriate-sized mesh pots (the two-gallon size, I believe), then five-gallon size paint strainers to keep the coco from eroding away into the runoff solution and to allow the roots to grow down into the buckets if they wanted. I filled each mesh pot with a mix of Canna coco (three parts) and chunky perlite (one part) for a little more aeration, just to be sure. Before transplanting, I flushed the buckets with RO water adjusted to pH 5.8, then a weak (300ppm) bloom cycle nutrient solution to “prime” the media and flush out any small particles. Since the initial crop was still in Hugos, I simply placed the big cubes with the plants on top of each mesh pot, to allow the roots to grow down into the bucket. For the next crop I’ll be eliminating the Hugos entirely, transplanting directly into the coco from smaller pots.
So how’d it work out? Stay tuned for the next exciting entry in my coco-nut saga!
