Table of Contents
This article is part of series where the Budsman gives his (not so) expert opinion on how to grow dank nugs using a coco coir setup. The first part of this series can be found here.
MORE NUTRIENTS =/= BETTER BUD
HEALTHY PLANT AND HEALTHY ROOTS = HEALTHY BUDS
Common Beginner Mistakes…
- Over-loving your plant (too many nutrients, too much water, etc.)
- Blindly following a feed guide…
- Growing a shitty seed (and not knowing if it was your fault, or the shitty hermie plant seed you just grew)
- Not reading your runoff EC/pH regularly – for hydroponic grows, you’ll need to be right on top of this until you know your environment and plant, as soil buffers better.
- Not being stealthy. No smell, no sell, no tell. Being smart in this regard can be simple, yet difficult. A carbon filter for flowering helps a lot, as does a negative pressure extraction room sealed to the outside. Some planning and an air conditioner or incense/glen20/lavender candles, and you’re good. Just make sure to have adequate airflow and ventilation.
- On that note, be extra kind to your neighbours.
- Tend to some legitimate plants if possible. That way, you can explain shit lying around
Problem Solving and Learning to Read Your Plant
There are both immobile and mobile nutrients. With coco, on the immobile side, you primarily worry about Ca and Fe with light supplementation. Root health is key, as well as not letting the medium dry out. This should take care of stuff okay, unless you have a needy strain.
Immobile nutrient deficiencies show up on the very newest growth and never fully recover – which means it will end up on the mid growth. Mobile nutrients (Mg and NPK, mostly) show up on older growth, as they can preferentially mobilise to the top of plant where needed. Again, always check pH/EC in and out before doing anything.
Interveinal Dechlorosis – Interveinal yellowing is usually a good sign of upward pH swing, generally meaning you’re overfeeding it with NPK and not allowing for enough runoff. A lack of Mg supplementation and poor root health are also common causes.
If your lower leaves are yellowing or browning, don’t worry. This can be normal, if they aren’t getting light. However, it could also be a sign of under feeding NPK. This is okay in vegetative states, but you want to be reducing environmental stress as the plant reaches flowering.
Topping, LST and Supercropping
I always recommend topping the plant back to its third node after one or two weeks in early vegetation phase. You want to let them recover in the 4L pot, then transplant them to the final 5-7L fabric pot.
Four to six weeks from seed should be more than enough to fill a 4x2ft space with two plants. Do plenty of training in this time; you should get some nice roots going.
LST (‘Low Stress Training’, or tying the plant down) can be achieved using some rubber plant ties, a couple of metal U rods to push branches down, and ‘supercropping’, or damaging the plant in a methodical manner. This will help everything set without constantly increasing tension, which will assist in having the plants spread out. The growth nodes that receive the most light (generally found centrally or at the top of the plant) become dominant relative to others on the same plant. They also have faster growth, leading to thicker stems and less node spacing.
You can stunt certain arms of the plant by tying them down further away from the light relative to others, or pulling off certain fan leaves which are growing too big.
You want to do the bulk of your lollipopping a week before flipping the lights, which can be hard to do well without knowing how the plant will stretch and respond to different kinds of stress
“Lollipopping” is about carefully clearing low budsights and leaves to increase airflow through the plant. This will allow the plant to concentrate its nutrients up the stems towards the buds receiving more light.
Once in post flip stretch you want to really focus on training the plants out evenly to create a nice, even canopy. Supercropping really helps here, as do SCROG nets. 1 ft of canopy with light getting to as much bud as possible is what you are going for. The flip can go for 10-22 days before early flowering well and truly starts (at least from my experience).
If you need to lollipop more than you first thought, the first 7-10 day post-flip is the best time (or so I’ve read). If you need to defoliate to get a little more airflow and light to bud sites, then day 21 and 45 are roughly good times to go for a decent size defoliation of fan leaves that are blocking bud sites or halting airflow.
Coco is fairly inert. You need to hit it a fair bit harder with root products and most things to have the same effect as soil. The speed of growth comes with some extra expense I guess, but you still get the buffer of coco being fairly insulative. It’s good for root growth, and has very good humidity properties, at least relative to full hydroponic setups.
Though there’s pretty much no point doing a coco or hydro grow without setting up some automation. I would recommend canna terra instead – the principals are similar, but only requires watering every few days.
The parts needed for 2 plants in three to seven gallon (10-25 L) pots are as follows:
- 1x submersible pump 750-1500L/hr, ~5-15W power use $15-40 (go to a good aquarium store)
- 1x programmable second timer to hook pump up for feeds $30-45
- 1x length of 13mm flexible irrigation tubing $2/metre
- 1x 13mm t piece connector (or a 19mm to 13mm t piece for the 1500L/hr pump) $1
- 1x packet of cable ties $2
- 2x feeder rings Watch out – the resistance in these and how many your running from one pump will determine what size pump you need $5-10 (you can get fancy sprinkler ones that need a lot more water pressure to come out evenly… but they do soak the coco a little more effectively)
All up, all this stuff should cost you about $AUD90. It takes about 5 minutes to physically setup, and another 5 to program the timer. You may need to do a fair bit of tinkering to dial feed times in, so keep that in mind.
Bird’s Eye View of Pump Setup
Sidenote: It helps to cable tie the pictured setup at the T-piece to keep everything tidy.
Pictured: pump in reservoir bucket, 13mm tubing (symbolised by dotted lines), connected to a T-piece feeding both plants at once. The Green circles are the feeder rings/plant pot itself.
You need to pamper the flowers, mostly. But, it’s also worth pushing them a bit with a nutrient uptake. Many flowers like 50% humidity or lower past the early flowering stage. This is thought to stimulate trichome production (but honestly, who knows).
With that said, they can take lower temperatures and humidity just fine, particularly in late flowering stage, comparatively speaking. Whether this is really beneficial outside of VPD is another unknown. It does seem to help with the fading/purpling, though.
A nice medium is 20-25C with good airflow turnover and air movement over the plants. Na (Salt) and Ca (Calcium) needs to be tapered down from early to mid flowering. Electrical Conductivity and the Potassium and Phosphorous levels will both need a spike during mid flower for 1-2 weeks, when the most rapid bud growth will occur.
As for Magnesium, it seems super variable with plants, at least for me. For some, calmag and A+B is plenty. Some I hand water with some Mg mixed in here and there.
~24 weeks per grow from seed with a 6 week vegetation, until you will have dried and cured your product (around the 2 week mark I usually find)
Germinating: 1-7 days
Vegetative: 4-8 weeks
Flowering: 9-12 weeks
Drying: 1-2 weeks
Curing: 2-4 weeks
Starting From Scratch
Expect ¼ – ½ of the yields you calculated above… and add a couple weeks of vegetation time. You’ve got no chance of hitting prize cuts by germinating random seeds and guessing their growth pattern for pre-flip training. Combine that with likely mistakes… and auto-flowers become a great option for people with limited space and time.
I recommend spending the time growing out a photoperiod and getting it through each stage nicely so you can learn to read your plant and adjust when necessary. Even at a ¼ of the optimum master grower type yields, you should still be saving money from the streets big time.
Water Quality and Measurement
Depending on your water’s EC/pH, investing in a Reverse Osmosis machine, or purchased water for seedling/vege stage, might be an idea. I got an RO and threw my pH out of the setup. I pretty much never need it now, and am glad for the relative lack of time spent on mixing.
pH takes around 30-60min to truly stabilise. It needs to be diluted before being added to the final mix, and it can take awhile to dial in for each stage of feeding.
Coco Coir is a pretty forgiving medium, if you treat it right. It needs an extra hit of Ca/Mg and less K (Potassium) than a truly inert medium. Mixed correctly and watered low/slowly, however, and the coco works a wonder. It can hold a lot of salts and remain saturated whilst still allowing for maximal root growth/aeration, which is why it’s considered semi-hydroponic. It can also take fairly decent hits on a single A+B nutrient, right from start to finish. It can even be treated like soil… but you are better off amending or going canna terra with this route, imo.
Expect to be misting the plants lightly twice daily. You’ll need to do this even more frequently in summer. Also expect to feed every couple of days days from seed to avoid lockouts early on in a 4L pot. I prefer to use a 2L mist spray bottle.
Low and slow is the goal: this will maximise unused runoff salt and will help the coco from becoming compact. A bit of perlite on top can help with fungus knats and prevent any watering from exposing surface roots lying in the coco. You’ll want to push it right up into late vegetation stage, leading up to 2-4 daily feeds in the final pot, once roots are established.
Once flipped to flower, watering can be done 2-12 times daily, depending on your preference. You’re aiming for 5-20% runoff with each feed. You don’t want EC out to ever be higher than EC in. You want pH stable at around 6 for feed in and out. Strips are fine… if you aren’t colour blind. Generally, you’re dealing with alkaline swings, and their causes can range from watering too fast and not running salts off, not letting tap water solutions settle before feeding, and overfeeding with nutrients.
A daily checking of your pH/EC of the feed solution and the pH/EC of your runoff is a big help, as it lets you know a lot about what’s happening in your medium, allowing you to react quick.
Rough EC Guide
- 0-1 EC in seedling/early vegetative
- 5-1.5 EC in vegetative
- 5-2.5 EC in stretch
- 5-3 EC in early to mid flower
- 1-2 EC late flower
- 0-1 EC for flush
At flush week, it’s most important that the EC of feed out is lower than what’s been going for 3-5 days. Flush it or go back to seedling feeds, but you don’t want to starve immobile nutrients right up until its properly finishing. Newbies will often flush and chop too early.
Tap water often takes care of immobile nutrients, if the pH is right. At the same time, starving the plant for the last two weeks of its cut time seems to cause little harm to yield and quality, at least as far as cost saving is concerned. But… until you’re growing things out proper, it’s best to just feed em right through. Especially the immobiles and microbes.
If you are not burning the plants at the end, flushing does little for the taste. The same processes are occurring in the plant (short of toxicity), except you’re stunting them if you try to overdo it.
Plenty of products (organic and/or chemical) are meant to be flushed for 2 weeks. The highest N and Ca needs are in late vegetative and stretch, then start going down after early to mid flower. P needs increase a bit in early flower. PK needs significantly spike mid flower for 1-2 weeks, as does overall EC. K needs seems to increase relatively slightly in late flower, and N and EC needs to decrease a fair bit at that time.
Having a clone to grow out with someone who has grown it before will make things 100 times easier for you. Plants are on a spectrum: they can either take A+B easy, or they may need all kinds of special care and supplements at different stages.
Remember: Roots = Buds
EC =/= buds – you just want the thing to be healthy, have a nice stable environment, to allow it to hit its genetic potential. Smashing in flower booster and burning your plant when it was perfectly happy can have anywhere from zero, to great, to detrimental, to bloody well hermie results. Likewise, if it didn’t have a happy life or form a nice healthy root base, don’t expect good things in flower.