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tobh's troll cave
- Thread starter tobh
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i like their profile better than the traditional slabs and feel like the roots have a better space to do their thing than if I ran in just 4" blocks. I could run purely in 4" blocks but the root exposure would annoy me and would open up more risk than I'm willing to tolerate. i also like the isolation between plants, which you don't get with traditional slabs.
last year's run with the unislabs was my best to date in the tent. cleanup took less than an hour, and i ended up tilling those into the raised garden bed at my old house. with these i figure i might as well experiment a bit post harvest, and the thought of harvesting peppers in early march sounds pretty damn appealing.
Rootsruler
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Coco mat works much like your slabs.
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don't get me wrong, i love me some coco. it was actually what moved me into hydro many moons ago. i just really like the cleanliness of hydro. since i've moved to the PNW, without fail, coco or peat-based medias lead to fungus gnats. haven't had issues with those in wool, dutch buckets, or F&D, and the cleanup from all these is almost as simple as taking shit outside and spraying it down with a hose, hitting it with bleach, rinsing it again, and letting it dry.
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alright. now with the slabs getting their initial soak, time to start pulling up data and techniques. given my thread at the old place didn't have external links, which i relied on for figuring out things my guy @Dirtbag wasn't privy to, gonna change shit up a little.
www.greenhousecanada.com
October 15, 2018 By Willem Gericke
Irrigation strategies should consider multiple factors, including substrate volume, drain holes, irrigation volumes, crop phase, water content and electrical conductivity within the rockwool slab.
In this article, we will focus on how to plan and execute a structured irrigation strategy, thus optimizing the rootzone, and consequently decreasing plant stress and potentially increasing yields.
There are a couple of factors to consider when planning an irrigation strategy. Grodan has devised the 6-Phase model for growing vegetable crops, a model where the growing period of a crop is divided into six phases. Phase 1 starts where the block is transplanted onto the slab, and Phase 6 ends when the last fruit is harvested. As most growers are currently in maximum production or Phase 5, we will interpret two different GroSens graphs which illustrate key points of interest. Note: GroSens measuring unit for WC is percentage.
Substrate volume
It all starts by having the right substrate volume. This is one critical factor, which can either have a vegetative or generative action on the crop. The ideal substrate volume for commercial vegetables is between 7.5 to 9.0 L/m2. When the substrate volume is on the lean side (less than 7.5 L/m2), it creates a more generative root zone, which forces the grower to increase the irrigation frequency, thus stimulating vegetative growth. During very generative growing conditions this approach is manageable, however, root health and fruit quality will be sacrificed during vegetative climatic conditions. Another problem is that the overnight dry back can become too severe during normal start and stop times, when using a small substrate volume. To counteract this, the grower must either start to irrigate earlier and stop later, or add a night cycle or two, which on the other hand can influence the plant’s physiology.
The opposite is also true. When the substrate volume is larger than 9.0 L/m2, it will result in plants growing vegetatively due to a small overnight dry back (3 to 5%). This makes steering the WC more difficult without using an extremely generative irrigation strategy (infrequent irrigation cycles). Therefore, root quality is compromised as well as nutrient refreshment.
Drain holes
Drain holes have a profound effect on WC (water content) and EC (electrical conductivity) management in the slabs. It is recommended, when used on gutters, that one to two drain holes are cut at the lowest point per 1.33 linear metre of a Grodan slab. It is advised that the drain holes are cut on the sides of the slab, approximately 2 to 3 cm from the edge of the rockwool. The cuts should be made from underneath the slab in an upward direction, and the foil must be opened, thus ensuring the efficiency of the drain holes. Opening the foil will ensure that the drain holes stay open, and the roots are air-pruned. When the slab is longer than 1.33 m, drain holes can be cut in the middle of the slab, but should never be made underneath a block. When this is done, the emitted water from the dripper will simply find the path of least resistance, causing false drain. Water content re-saturation and EC refreshment in the slab will be compromised, and there can be differences in WC and EC readings within the slab. When multiple blocks are used on a slab, and the distance between the blocks is limited, attention should be paid to the distance from the dripper in the block to the drain hole. The ideal distance from dripper to drain hole is 20 cm, and the dripper can simply be moved to the other side of a block, to increase the distance. This will have a beneficial effect on WC re-saturation and EC refreshment, and will also decrease variance within a slab.
Calculating irrigation volume
A structured irrigation strategy is necessary to generate a balanced plant, and can aid in counter steering a plant, as determined through crop registration. The first four to six irrigation cycles in the morning should range between 4 to 6% of the substrate volume, and is normally followed by irrigation cycles of 3% of the substrate volume. The following calculations will help to illustrate.
Determining slab volume:
Slab dimension: 100 cm x 20 cm x 7.5 cm = 15 000 mL or 15 L slab volume.
Blocks per slab: 4
Heads per block: 2
Plant density: 4.2
Drippers per slab: 6
Determining substrate volume per m2:
15 000 mL / (4 blocks x 2 heads)
= 1875 mL
1875 mL x (4.2 plant density) = 7875 mL or 7.875 L/m2 of substrate volume
Determining a 4% cycle:
7875 mL x (0.04) = 315 mL/m2
Determining the dripper density per m2
6 drippers / (4 blocks x 2 heads)
= 0.75
0.75 x (4.2 plant density) = 3.15 drippers/m2
(315 mL/m2) / (3.15 drippers/m2)
= 100 mL/dripper
The time needed to irrigate 100 mL/dripper when using a 2.2 L/hr dripper is determined as follows:
2200 mL (dripper) per 60 minutes (1 hour) = 36.67 mL/minute, thus:
(100 mL) / (36.67 mL/ minute) = 2.72 minutes or 163 seconds.
The same calculations apply when determining a smaller shot of 3% or a larger shot of 6%.
The varying cycle size of 4 to 6% is determined by a combination of factors which are influenced by the season, start and stop times and overnight dry back. Prominent differences between Fig 1 and Fig 2 will be touched on, emphasizing the key points to focus on, which will reduce plant stress and potentially generate a stable maximum production, which is generated through a structured irrigation strategy.
Water content profile
Any grower knows that when plant stress is reduced, a plant will function better. This can be accomplished through applying a structured irrigation strategy per plant growing phase in conjunction with the climate. The first thing to note when analyzing the WC (blue line) in Fig 1 is that there is no WC gradient decrease (purple square) just before the first morning irrigation cycles commence on the different days. This shows that the plants weren’t transpiring when the first irrigation cycle was given, potentially leading to active water uptake or as most growers refer to it, as increased root pressure, which can negatively influence plant physiology. Remember the golden rule, transpiration before irrigation!
Second is the fluctuating morning WC percentage over three days (grey line), varying between 60 and 68% before the morning cycles commence. This varying morning WC percentage creates plant stress that needs to be minimalized, and is determined by the irrigation start and stop times and overnight dry back. A late start and early stop time will generate a steep WC gradient, resulting in a big dry back (black square). In this scenario three night shots were given in Fig 1. to counteract the overnight dry back from becoming too severe, thus avoiding a too-low morning WC percentage. Night cycles are normally applied to compensate for incorrect start and stop times, thus limiting severe overnight WC decreases. It can also be necessary to give night cycles when the substrate volume is on the lean side, and the heating pipes are on, stimulating a generative growing climate and reducing the slab WC.
The morning cycle volume (4 to 6% of the substrate volume) is determined by the previous night’s dry back, and when the two days are compared it is evident that eight cycles were needed on May 31 vs the five cycles on June 1. If the eight cycles were reduced to five to six cycles while increasing the volume, drain would have been realized earlier and simultaneously increased the efficiency of EC control. The large morning cycles will re-saturate the WC in the slab and simultaneously refresh the EC. Also, the large morning cycles (between 4 to 6%) will ensure that drain is realized on time, thus reducing the EC (red line) before noon. It is advised that the irrigation cycles start two to three hours after sunrise and is big enough to realize drain at around 400 J/cm2 or around 600 W/m2, or four to five hours after sunrise. The small irrigation cycles observed in Fig 1. represent a nearly flat line, thus indicating very small dry backs between the cycles. To ensure that the oxygen levels in the slabs are replenished, the WC dry back percentage between the cycles must decrease between 1.5 to 2% before the next irrigation cycle is re-applied. Following this action will ensure that the rootzone stays active, during changing climatic conditions. Also, bear in mind that dissolved oxygen (DO) levels decrease with an increase in water temperature. The decreasing dissolved oxygen (DO) levels in the slabs have a profound negative effect on root formation. Newly formed roots are necessary to ensure the active uptake of water and nutrients – this emphasizes the importance of focusing on start and stop times as well as overnight dry back in conjunction with changing climatic conditions.
The first key point to focus on when interpreting Fig 2 is the steep WC decrease (between 1 to 2%) which occurs after dawn until the first irrigation cycle starts. Each day tends to have the same curved decrease in WC, and this clearly signifies that the plants were transpiring before irrigation started. It is a well-known fact that root hairs increase the root area and helps with water and nutrient absorption. Also, root hairs are actively initiated after sunrise until the first irrigation, and they are formed within hours. When there is little time from sunrise until first irrigation, root hair formation can be sacrificed. Therefore, it’s important to ensure that plants are actively transpiring before irrigation is activated. The starting WC percentage varies by only 2% over a seven-day period, which has a positive influence on rootzone management during the maximum production phase. This was accomplished despite the changing water temperature (green line) indicating a varying climate, and was achieved by focusing on the irrigation start and stop times and achieving a stable overnight dry back between 7 to 8%.
Although the number of morning irrigation cycles and water temperature (green line) differed between Thursday and Friday, the day dynamic WC percentage stayed stable between 64 to 65%, and it was achieved by changing the number and volume of irrigation cycles needed to reach the day dynamic WC percentage. Thus, the volume and number of irrigation cycles necessary to accomplish this was determined by the overnight WC decrease (dry back). An overnight dry back of between 8 to 10% is adequate to maintain an active rootzone. This is achieved by generating a 3% dry back over a three-hour period since the last irrigation ceased. It is clear to see that the irrigation morning volumes were large enough as the EC was reduced effectively before noon, and was stabilized during the rest of the irrigation cycles. This is paramount, as plant stress is severely reduced by having the lowest EC during the highest radiation. To achieve this, drain must start around 400 J/cm2 or at around 600 W/m2. Although, the irrigation cycles that followed the large morning cycles (blue line) were small, there was sufficient WC dry back between the cycles as the graph amplitudes varied around 1.5%, thus ensuring an oxygenated slab and maintaining an active rootzone during maximum production.
Takeaways
Managing the rootzone: Irrigation volumes and EC, WC graphs - Greenhouse Canada
A structured irrigation strategy can help optimize the crop’s rootzone and improve yields.
www.greenhousecanada.com
Managing the rootzone: Irrigation volumes and EC, WC graphs
A structured irrigation strategy can help optimize the crop’s rootzone and improve yields.October 15, 2018 By Willem Gericke
Irrigation strategies should consider multiple factors, including substrate volume, drain holes, irrigation volumes, crop phase, water content and electrical conductivity within the rockwool slab.
In this article, we will focus on how to plan and execute a structured irrigation strategy, thus optimizing the rootzone, and consequently decreasing plant stress and potentially increasing yields.
There are a couple of factors to consider when planning an irrigation strategy. Grodan has devised the 6-Phase model for growing vegetable crops, a model where the growing period of a crop is divided into six phases. Phase 1 starts where the block is transplanted onto the slab, and Phase 6 ends when the last fruit is harvested. As most growers are currently in maximum production or Phase 5, we will interpret two different GroSens graphs which illustrate key points of interest. Note: GroSens measuring unit for WC is percentage.
Substrate volume
It all starts by having the right substrate volume. This is one critical factor, which can either have a vegetative or generative action on the crop. The ideal substrate volume for commercial vegetables is between 7.5 to 9.0 L/m2. When the substrate volume is on the lean side (less than 7.5 L/m2), it creates a more generative root zone, which forces the grower to increase the irrigation frequency, thus stimulating vegetative growth. During very generative growing conditions this approach is manageable, however, root health and fruit quality will be sacrificed during vegetative climatic conditions. Another problem is that the overnight dry back can become too severe during normal start and stop times, when using a small substrate volume. To counteract this, the grower must either start to irrigate earlier and stop later, or add a night cycle or two, which on the other hand can influence the plant’s physiology.
The opposite is also true. When the substrate volume is larger than 9.0 L/m2, it will result in plants growing vegetatively due to a small overnight dry back (3 to 5%). This makes steering the WC more difficult without using an extremely generative irrigation strategy (infrequent irrigation cycles). Therefore, root quality is compromised as well as nutrient refreshment.
Drain holes
Drain holes have a profound effect on WC (water content) and EC (electrical conductivity) management in the slabs. It is recommended, when used on gutters, that one to two drain holes are cut at the lowest point per 1.33 linear metre of a Grodan slab. It is advised that the drain holes are cut on the sides of the slab, approximately 2 to 3 cm from the edge of the rockwool. The cuts should be made from underneath the slab in an upward direction, and the foil must be opened, thus ensuring the efficiency of the drain holes. Opening the foil will ensure that the drain holes stay open, and the roots are air-pruned. When the slab is longer than 1.33 m, drain holes can be cut in the middle of the slab, but should never be made underneath a block. When this is done, the emitted water from the dripper will simply find the path of least resistance, causing false drain. Water content re-saturation and EC refreshment in the slab will be compromised, and there can be differences in WC and EC readings within the slab. When multiple blocks are used on a slab, and the distance between the blocks is limited, attention should be paid to the distance from the dripper in the block to the drain hole. The ideal distance from dripper to drain hole is 20 cm, and the dripper can simply be moved to the other side of a block, to increase the distance. This will have a beneficial effect on WC re-saturation and EC refreshment, and will also decrease variance within a slab.
Calculating irrigation volume
A structured irrigation strategy is necessary to generate a balanced plant, and can aid in counter steering a plant, as determined through crop registration. The first four to six irrigation cycles in the morning should range between 4 to 6% of the substrate volume, and is normally followed by irrigation cycles of 3% of the substrate volume. The following calculations will help to illustrate.
Determining slab volume:
Slab dimension: 100 cm x 20 cm x 7.5 cm = 15 000 mL or 15 L slab volume.
Blocks per slab: 4
Heads per block: 2
Plant density: 4.2
Drippers per slab: 6
Determining substrate volume per m2:
15 000 mL / (4 blocks x 2 heads)
= 1875 mL
1875 mL x (4.2 plant density) = 7875 mL or 7.875 L/m2 of substrate volume
Determining a 4% cycle:
7875 mL x (0.04) = 315 mL/m2
Determining the dripper density per m2
6 drippers / (4 blocks x 2 heads)
= 0.75
0.75 x (4.2 plant density) = 3.15 drippers/m2
(315 mL/m2) / (3.15 drippers/m2)
= 100 mL/dripper
The time needed to irrigate 100 mL/dripper when using a 2.2 L/hr dripper is determined as follows:
2200 mL (dripper) per 60 minutes (1 hour) = 36.67 mL/minute, thus:
(100 mL) / (36.67 mL/ minute) = 2.72 minutes or 163 seconds.
The same calculations apply when determining a smaller shot of 3% or a larger shot of 6%.
The varying cycle size of 4 to 6% is determined by a combination of factors which are influenced by the season, start and stop times and overnight dry back. Prominent differences between Fig 1 and Fig 2 will be touched on, emphasizing the key points to focus on, which will reduce plant stress and potentially generate a stable maximum production, which is generated through a structured irrigation strategy.
Water content profile
Any grower knows that when plant stress is reduced, a plant will function better. This can be accomplished through applying a structured irrigation strategy per plant growing phase in conjunction with the climate. The first thing to note when analyzing the WC (blue line) in Fig 1 is that there is no WC gradient decrease (purple square) just before the first morning irrigation cycles commence on the different days. This shows that the plants weren’t transpiring when the first irrigation cycle was given, potentially leading to active water uptake or as most growers refer to it, as increased root pressure, which can negatively influence plant physiology. Remember the golden rule, transpiration before irrigation!
Second is the fluctuating morning WC percentage over three days (grey line), varying between 60 and 68% before the morning cycles commence. This varying morning WC percentage creates plant stress that needs to be minimalized, and is determined by the irrigation start and stop times and overnight dry back. A late start and early stop time will generate a steep WC gradient, resulting in a big dry back (black square). In this scenario three night shots were given in Fig 1. to counteract the overnight dry back from becoming too severe, thus avoiding a too-low morning WC percentage. Night cycles are normally applied to compensate for incorrect start and stop times, thus limiting severe overnight WC decreases. It can also be necessary to give night cycles when the substrate volume is on the lean side, and the heating pipes are on, stimulating a generative growing climate and reducing the slab WC.
The morning cycle volume (4 to 6% of the substrate volume) is determined by the previous night’s dry back, and when the two days are compared it is evident that eight cycles were needed on May 31 vs the five cycles on June 1. If the eight cycles were reduced to five to six cycles while increasing the volume, drain would have been realized earlier and simultaneously increased the efficiency of EC control. The large morning cycles will re-saturate the WC in the slab and simultaneously refresh the EC. Also, the large morning cycles (between 4 to 6%) will ensure that drain is realized on time, thus reducing the EC (red line) before noon. It is advised that the irrigation cycles start two to three hours after sunrise and is big enough to realize drain at around 400 J/cm2 or around 600 W/m2, or four to five hours after sunrise. The small irrigation cycles observed in Fig 1. represent a nearly flat line, thus indicating very small dry backs between the cycles. To ensure that the oxygen levels in the slabs are replenished, the WC dry back percentage between the cycles must decrease between 1.5 to 2% before the next irrigation cycle is re-applied. Following this action will ensure that the rootzone stays active, during changing climatic conditions. Also, bear in mind that dissolved oxygen (DO) levels decrease with an increase in water temperature. The decreasing dissolved oxygen (DO) levels in the slabs have a profound negative effect on root formation. Newly formed roots are necessary to ensure the active uptake of water and nutrients – this emphasizes the importance of focusing on start and stop times as well as overnight dry back in conjunction with changing climatic conditions.
The first key point to focus on when interpreting Fig 2 is the steep WC decrease (between 1 to 2%) which occurs after dawn until the first irrigation cycle starts. Each day tends to have the same curved decrease in WC, and this clearly signifies that the plants were transpiring before irrigation started. It is a well-known fact that root hairs increase the root area and helps with water and nutrient absorption. Also, root hairs are actively initiated after sunrise until the first irrigation, and they are formed within hours. When there is little time from sunrise until first irrigation, root hair formation can be sacrificed. Therefore, it’s important to ensure that plants are actively transpiring before irrigation is activated. The starting WC percentage varies by only 2% over a seven-day period, which has a positive influence on rootzone management during the maximum production phase. This was accomplished despite the changing water temperature (green line) indicating a varying climate, and was achieved by focusing on the irrigation start and stop times and achieving a stable overnight dry back between 7 to 8%.
Although the number of morning irrigation cycles and water temperature (green line) differed between Thursday and Friday, the day dynamic WC percentage stayed stable between 64 to 65%, and it was achieved by changing the number and volume of irrigation cycles needed to reach the day dynamic WC percentage. Thus, the volume and number of irrigation cycles necessary to accomplish this was determined by the overnight WC decrease (dry back). An overnight dry back of between 8 to 10% is adequate to maintain an active rootzone. This is achieved by generating a 3% dry back over a three-hour period since the last irrigation ceased. It is clear to see that the irrigation morning volumes were large enough as the EC was reduced effectively before noon, and was stabilized during the rest of the irrigation cycles. This is paramount, as plant stress is severely reduced by having the lowest EC during the highest radiation. To achieve this, drain must start around 400 J/cm2 or at around 600 W/m2. Although, the irrigation cycles that followed the large morning cycles (blue line) were small, there was sufficient WC dry back between the cycles as the graph amplitudes varied around 1.5%, thus ensuring an oxygenated slab and maintaining an active rootzone during maximum production.
Takeaways
- Small and large substrate volumes influence the ability to control the WC and EC within the rootzone; small substrate volumes force vegetative irrigation strategies and vice versa
- The quantity and placement of drain holes per slab will influence the WC percentage steerability and EC refreshment within the slab
- Irrigation volume strategies are calculated per substrate volume which differs between growers, and large morning cycles between 4 to 6% of the substrate volume is used to re-saturate the WC and refresh the EC, while smaller 3% cycles are used in the afternoon to maintain the day WC and stabilize the EC
- Maximum production is enhanced by maintaining a stable day dynamic WC and the EC is controlled in a managed way through utilizing a structured irrigation strategy
Observer
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Ahh right, they are meant to set on top and grow in, I was stuck on "insertion" into the holes/slab lmao
-sleep deprived
That's even better I could just load up 4inch cubes or so.
Clean
Ty sir.
Rootsruler
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He popped some pencil thick roots through some 4"(?) cubes and is now plugging those roots into a larger rhizosphere. My spidey senses keeping saying fertigation........
Observer
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Yup those slabs are dope for high-freq-fert and crop steering.
Are you going to be messing with crop steering this round too?
Wanted to attempt it at some point, thought somewhat possible to manually place pot on scale and take a bunch of measurements between the dry-saturated range and record them to get an idea on water content % and manipulate from there, definitely need an E.C meter then.
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to an extent, yeah. i won't be going based off weights, though. between EC and the texture of the wool you can get a pretty solid gauge of the WC, albeit like a butt dyno after installing new parts on your car. i try to avoid fucking with the slabs once they're loaded up just because of how fragile the rockwool structure is when saturated. can't really call my method crop steering but it falls in line with the basic concepts and is high fertigation so we'll call it crop "steering"
some day i'll get some microcontrollers and sensors, maybe. not sure if i want to invest that heavily into this style of growing vs taking the plunge into RDWC.
Observer
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Gotchato an extent, yeah. i won't be going based off weights, though. between EC and the texture of the wool you can get a pretty solid gauge of the WC, albeit like a butt dyno after installing new parts on your car. i try to avoid fucking with the slabs once they're loaded up just because of how fragile the rockwool structure is when saturated. can't really call my method crop steering but it falls in line with the basic concepts and is high fertigation so we'll call it crop "steering"
some day i'll get some microcontrollers and sensors, maybe. not sure if i want to invest that heavily into this style of growing vs taking the plunge into RDWC.
Good to know
I'm missing my first dwc bucket I tried, I just didn't get to flower her out and I vegged her higher than the LED and to tent ceiling in a 2x4 lol.
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I've had pretty decent luck with my first RDWC. There are a lot of knowledgeable guys here in that aspect. So far I'm loving it and glad I went this route, but your grow here has really stimulated my curiosity.
Rootsruler
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How were you able to pop such healthy thick roots? Is it genetic to the cultivar or are you using some sort of root enhancer?
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awesome, glad you're digging it so far. as long i remember to set the pump timers back on auto and keep the lights from going full send, it should be a much smoother run than last time.
i truly think it's because i used the 3" delta blocks instead of the 4" blocks that are more common. finding the 3" blocks took some digging, but they're what @Dirtbag uses and i can really see why now. rooted the clones in rapid rooters, then just shoved the well rooted rooters into the deltas, let the blocks get more dry than usual until the roots were sucking the things dry within a day, and now we're on the slabs.
i'll repeat the same process by not water for a few days, checking moisture content in the slabs by feel, then will start hand watering for probably another week, then automate the fertigation cycles per usual.
Rootsruler
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So you keep the water content in the cubes low to spur root growth? Would you say that "dry" is very lightly damp if you split the cube or actually bone dry?
When I propogate in dirt I water them in thoroughly then let them dryback. I might water them lightly one more time but usually one watering is all I need before they're firmly rooted.
Dirtbag
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Can't speak for @tobh but I'll add my 2c, the idea for me is just to let the blocks get quite dry, but not quite bone dry. Bone dry is never good. But you want to let them dry up significantly which can take a few days after transplant. It will force the roots to explore a lot faster than if they had constant saturation.
The same thing applies to a more dramatic extent if you plant clones directly into Hugo 6x6's. If the block is kept saturated or you plant in them while too wet, they take forever to root. Let them get good and dry before putting a cut in them and you get roots hella faster.
Rootsruler
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Just so I have a good parallel. If I took a 4" grodan block and spun it around like I was roping cattle to remove moisture. Or like a well rung out sponge? Would you consider that the limit of dry you want to get to before rehydrating? If I do have to rehydrate would a light watering be advisable to keep the media on the dryer side?
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So, I go based off weight by feel. I waited until they felt almost the same as a completely new, unsaturated block. You can also visually tell because they go from a darker algae type green to a sandy whitish green.
Basically the same exact thing you do in soil, it just happens way faster in wool
Dirtbag
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Probably a little drier than that. After transplant I wait for the block to feel alarmingly lightweight, but should still feel slightly damp on the bottom. And no, if you have to rehydrate a block I prefer to dunk them to full saturation to reduce or eliminate hotspots of dry salts in the wool. The only exception I would make to that is when using the Hugo because they can be a massive pain in the ass when they're fully saturated.
A 3 or 4" block I dunk in a bucket of nutrient solution to feed. It's hard to fuck up the 3" cubes though, they just root so much faster than anything else I find.
I just check on them once a day and if they feel suddenly weightless, give them a dunk. Repeat until they're rooted enough for the slab
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This guy has all the wisdom, gents. I just pretend to know WTF I'm doing, it's really all dirtbag telling me how not to fuck up in the background
Dirtbag
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Exactly right, it should feel like you're picking up a brand new unsaturated block. When it feels light as a feather, it's time to water again.
Last edited:
Dirtbag
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This guy has all the wisdom, gents. I just pretend to know WTF I'm doing, it's really all dirtbag telling me how not to fuck up in the background
Nah, don't sell yourself short, most of the shit I say was told to me by other people too.
I'm happy to see the techniques getting passed along.
Observer
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I may just move to rockwool
Sold on cleanliness and not fucking with coco particles/dirt/gnats.
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it has its own caveats, like the fact that it's not biodegradable and recycling facilities that will accept it are exceedingly rare. i've had some "greener" types outright call me evil for promoting it. it's also much less forgiving to fuck ups. you have to be on top of your game, especially with heavily rooted plants that are drinking a ton.
recovering from pH and EC issues is relatively easy but if you let it dry out too much, it almost seems to suck the moisture out of the plants (can't confirm that's the case).
you also have to be very mindful of the space you have to grow in. these plants move way faster than coco plants, and make soil plants look like sloths.
however, you can push the plants harder and be more aggressive with pruning than in other mediums due to the speed. basically every bit of research that's been done on crop steering is specific to rockwool -- some claim to do it in coco, but rockwool is the preferred medium for crop steering. the cleanliness is better than just about any other system I've ran including F&D and NFT. cleanup and resetting is a much simpler ordeal when you're not having to contend with potentially tens of gallons of nutrient solution. there is a lot of aftermarket support in the form of irrigation systems and whatnot. and, unlike most soil-like mediums, you can run subsequent crops in the same media without having to pull out all the roots as long as you run sterile.
Observer
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That's what I was reading too, sucks it's not too recyclable or green though.
When I first bought a cube a year or so ago I looked at the thing like wtf do I do with this?
Much more confident now, definitely seems something youd want to have automated though.
And now that I've taught my self coco and DWC I feel ready for the wool
Definitely gotta get the appropriate tools and gear though it seems to make it go smoother.
EC/pH/probes/automation stuff
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yeah, until you feel comfortable with your nutrients. i don't even check the EC of my solutions anymore but I've used the same nutrients for like four years now. Definitely need the EC meter to check the media, though. everything about wool is concerned about the root zone.
otherwise, a couple pumps, some plumbing, some extra timers, and you're ready to do it to it. you can even treat the shit damn near exactly the same as high fertigation coco if you want.
Observer
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Sweet, thanks tobh.
Gotta get this place in order, and get on it down the line.
Hard to work around the active little one lol.
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i hear ya. finally have an empty house so I'm finally knocking out the last bits of "heavy" work i've needed to get done and couldn't without constant distraction or risk of injury. one thing at a time, ya know.