Growing Guide


<8 October - Work in Progress>

 

Since it's now legal to grow cannabis in South Africa, we are making a guide for beginners who want to grow at home.  There are lots of techniques.  These are just the methods we use, to get you started. 

 

The table of contents:

1. Germinating

2. Transplant

3. Light

4. Training

5. Harvesting

6. Curing

 

 Pro tip: Dechlorinated water

Municipal tap water is chlorinated, to kill bacteria. But it's not great for humans, or plants. Ideally you should use rain water for your plants. But if you use tap water, either let it sit for 24 hours, or get a reverse osmosis filter.  Rain water and filtered water lack some minerals, though, such as calcium, so be aware of this.

 

1. Planting a seed

First step is to get yourself a seed, or a clone/cutting. Seeds are categorized as 'regular', 'feminised' and 'auto'. Regular seeds are 50/50 male and female.  Feminised seeds are female. Auto seeds start flowering automatically after a few weeks, rather than by detecting a shortening of daylight hours.  

Put the seed in some wet (but not waterlogged) tissue paper, room temperature, and keep it in the dark.  Check on it every day, until it sprouts.

Another option is to put the seed straight into a wet Jiffy pellet. Jiffy pellets will maintain a good air/water ratio for a few days, allowing a good germination rate.  

It's not necessary, but seedlings (or clones) prefer humid environments, so if you have a humidity dome, use it.

Outdoors, seasons will affect your results, if you're growing outside. Some times of the year, the plant will keep growing vegetatively for months, some times of the year, it will go directly to flower in a matter of weeks. Be aware that if you leave a plant in flower right through the Summe,r without harvesting, it will probably "reveg"

Important concept: Veg / Flower

When a seed germinates, it is in a vegetative state ("vegging").  That means it hasn't flowered yet.  A "short day" plant such as cannabis will flower when the days get shorter.  (This 'photoperiodism' doesn't apply to 'auto' plants.) 

Outside, this relates to the seasons.  Indoors, a vegetative state is maintained by keeping lights on the plant for 18 hours/day or more, and a flowering state is induced by dropping the length of the 'day' to 12 hours or less.  You should "switch to flower" when the plant is about half its desired final size.  Once "in flower", the plant will start focusing on producing buds. 

"Mother plants" are permanently kept in a vegetative state, so that cuttings ("clones") can be taken.

  

2. Transplanting into your growing medium 

Next, move the sprouted seed into a larger pot. Just a little pot for now. If you used the toilet paper method, just make a little hole 2cm deep in your growing medium, gently drop the seed in with root facing down, and cover it back up, half a centimeter.  If you used a Jiffy Pellet, you can wait until the roots are growing out of the pellet before transplanting.

A nice thing to do for the plant, when repotting, to give the plant a boost, is to add a beneficial fungus, mycorrhizae, into the hole where the pellet is placed.

Seedlings have enough chemical energy in their seeds to last them about a week, so just feed them plain water for the first week. Giving the seedling nutrients too soon can cause "damping". The stem shrivels up. Once, we were able to cut the stem above the damping, dip it in rooting powder, shove it in a jiffy pellet, and it survived, and regrew roots, but this is a lucky case.  Usually damping means game over.  

 

Important question: What growing medium to use?

You can either use soil, or a hydroponic medium. Or you can go "full hydro".  

Soil is simpler, because if there are enough nutrients and fertilisers in the soil, you just have to water the plant.

But some potting soils are sandy, and can become waterlogged, which is a quick way to kill a plant. The main thing to note, is that roots want both water and oxygen, so soil should be damp. Not soaking wet. If you have any hydroponic medium, like perlite, or leca, or coco coir, mix it in with the soil, because it will help with drainage, and protect against waterlogging.  

If you're just at your local garden store, choose a 'master mix' if in doubt.  If there's options, make yourself a mix. You can experiment. We've used 3/4 'potting soil' and 1/4 'compost', with a bag of worm castings mixed in, before.  Worked fine!

Hydroponic mediums are a big topic on their own. We'll get back to it later, as hydroponics is a huge topic.

 

 3. Let there be light

If you are growing outside, use the Sun. Weed is not a shade-loving plant, like a "delicious monster" plant. With the Sun, you can generally expect the plant to grow naturally, vegging, and flowering, depending on the seasons.  If you bring an indoor vegging plant outdoors, it will likely start flowering within a few weeks.  Growing outdoors requires ensuring that the plant is not receiving artificial light from a street light or security light, through the night.

Seedlings and clones will do better indoors, or at least in a greenhouse, where you can control the environment.  The wind can be strong, and the Sun is very bright.  The growing medium can dry out quickly under strong Sun light.  

When seedlings emerge, make sure they're already under light. Hit the ground running. If there's not enough light, the seedling will stretch. Starting your seedlings under a cooler CCT (colour temperature) will help with stretching.  If germinating under a warmer CCT light, it will probably stretch, no matter what, but as long as it gets enough light, it should make a come back. 

Be aware of the 'inverse power law'.  With a point-source light, every time you halve the distance to the light, you quadruple the power the plant is receiving. 

Indoor lights, especially with lenses, can have a very different level of brightness between 15cm and 30cm distance. Find out what a good canopy distance range is, for the light you're growing with.  This can be worked out with a PAR meter, or with a lux meter if only using white light. 

 

Single or Multiple growing areas

If you only grow 'auto' plants, you will only need one growing area, and can set your timer for 18 hours/day.  Almost any spectrum will work.

You can also use a single growing area with non-auto seeds, if you are planting all your seeds at once.  The issue here is that for normal "short day", i.e., non-auto seeds, it is the change from 18 hours to 12 hours/day, which signals to the plant that "Winter is coming", and tells it to start flowering.  In a single growing area, you can't have some plants on 18 hours/day and some on 12 hours/day.  When you switch to 12 hours, all your plants will start flowering in a week or two. 

If you "switch" a plant early, you usually end up with a single-cola lollipop.

So most growers end up with at least two growing areas.  One for the mother plants, vegging plants, and seedlings, and one for the flowering plants.  This also allows you to use two spectrums.  A cooler spectrum, running 18 hours in the veg area, and a warmer spectrum, running 12 hours in the flowering area.

 

 4. Train the plant

This is a fun part, and there are many techniques. We'll briefly cover some of the basic ideas: 

Topping - While vegging, cut the stem above a branching node. This redistributes growth, leading to more colas.  It turns the tree into more of a bush. Wait until there are at least 3 to 6 branching nodes. If you start too soon, it will slow down the plant's growth. Give plants at least a week or two more of veg, after topping, if you are switching it to flower. Many people maintain a mother plant, which ends up very bushy because of all the topping.  For mother plants, the purpose is to propagate clones. But it works on any plant, to help it fill out the canopy by redistributing plant hormones, to other growth tips.

(The cut-off top can usually become a clone.  We'll cover cloning later.) 

LST (Low Stress Training) - This is when you use a string to tie down branches. This trains branches sideways, and causes a wider, bushier canopy. Since lighting is mostly top-down, this helps the plant get more direct light. This allows a technique called "scrogging".  Tie it down at 90 degrees, if you can.  Don't worry, the leaves will be aiming up again, in a few hours. You can, and should end up spending a lot of time doing this, on all of your plants.  Keep the rope ties a bit loose. It's easy to snap your main stem down the middle, using this technique. That may or may not be a good thing.  When this happens, just duct tape it back together.

Supercropping (High Stress Training) - Like a "what doesn't kill you, makes you stronger" technique, supercropping is probably the most well-known of the higher stress training techniques. This involves snapping a branch, trying not to break the skin - more like a squeeze and bend, crunching it a bit, scrunching just enough to bend it. Then you duct-tape it back in place, letting it heal. 

The plant's attempts to repair the snapped branch often results in a sturdier stem. Beware that sometimes you can mess this up, and destroy the branch, by accident. But on the positive side, when you accidentally break a branch, you might be able to tape it up, and pass it off as "supercropping".

 

Scrog (Screen of green) can be done using topping and LST. The idea is to veg your plants until you can fill out a canopy.  

A well scrogged plant is equivalent to having multiple smaller plants.  In the US states with medical marijuana laws, there are sometimes "plant counts".  In Spain, you can have a certain number of plants.  This makes a blanket of colas, making use of all "growth tips", allowing secondary branches to get as much light as the top/main colas.

Lollipopping involves removing removing the lower leaves and growth tips.  This can be done around the time you're switching to flower, and the plant won't spend as much energy growing lower branches, and instead focuses on flowering the top layer, which have the best chances.

 

5. Harvest

When the buds are looking ready, pistils turning red, the fan leaves are turning yellow, it might be getting time to harvest.  

The only way to be sure is to check the trichomes, with at least a 30X loupe or a microscope of some sort. The trichomes are the small globules giving the buds and leaves a frosty or crystally look. The THC forms in them, making them cloudy. Once you cut the branches, there's still a week or two, of THC forming, during drying and curing.

If you want a lighter weed, you can harvest when the ratio between clear and cloudy trichomes is still low.  We've done this on some high THC strains, to limit their potency.  (Be aware that 25% THC strains are very stong, even for experienced smokers.)  When it's time to harvest, the longer you wait, the more cloudy, and eventually, the more amber, the average trichomes will become. If you are growing a CBD strain, you need to wait for amber trichomes to form, in order to fully express the CBD content.  The cloudier the trichomes, the more "couch-locking" the experience. Couch lock is like when you end up watching the whole Lord of the Rings trilogy, accidentally.

Many people flush the growing medium with water, and put the plants in darkness for two days, to decrease excess nutrient buildup. You generally want it dark during the drying process.  You want photosynthesis to stop.

Drying can last anywhere between a few days and a few months. Usually it takes about a week, of hanging upside down.  

You want to dry the buds in a well controlled environment.  Temperature and humidity needs to be moderated.  Something like a cupboard, slightly ajar, will usually do ok.  18 degrees Celcius, and 50% humidity.  Allow some fresh air exchange, but not a direct fan, as that will speed up the drying.

Manicuring buds is done with scissors, after removing a branch. Any large leaves are removed, and other leaves are cut back, close to the buds. You can remove fan leaves before drying, and you can cut back other leaves as to your preference. 

 

6. Curing

Put the manicured buds in an airtight container. Burp it daily, like a baby. Rather use glass, than plastic containers, if you can.  Try wait at least two weeks.  Four weeks or more, if you are a connoisseur. It's easy to get excited and smoke a joint after a few days of curing, and if you let it get bone dry, you can probably smoke it - it won't get much better.  But the indescribable dankness of some strains - the strain's distinctive smell and flavours are developed during curing. Seed sites like Cannapedia, describe strains with the same level of florid detail as wine makers use, in their craft. eg. "hints of apple and smoked mahogany".

"Burping", or "breathing" releases excess moisture.  The daily fresh air is very important, as a closed jar is like a little ecosystem of bacteria and fungus, who will grow, if you give them the chance. Keeping it in a glass jar, opening it daily for a few minutes, is a common method of curing. During curing, the chloroplasts die, along with it, the grassy herbaceous smell.  Cannabinoid profiles change, terpenes develop, and though the plant life processes come to an end, the process is drawn out, lowering the moisture level gradually.  It keeps the bud from drying out completely, and getting brittle.

If after a day in the jar, the smell is mouldy at all, take them back out.  They're not dry yet.

This part is one of the most important, and it is really easy to mess up.  Curing gets easier with practice, but for first time growers, this requires intuition and attention to detail, because if gets too temperate and humid in the jar, you will probably lose that whole jar to mould. If there's any doubt, be sure to rotate the buds and make sure there's no mould. Use many jars, if you can, so you don't put all your eggs in the one basket.