Sea of Green (SOG) is a cultivation method that takes advantage of the entire cultivation area by filling it with a large number of plants.
The idea, in short, is to fill the area with as many plants as possible, creating a “green sea”. The pots are often so close that they touch each other.
It is a productive technique as it has the advantage that with many small plants you can get a massive yield in a short time. The number of plants alone outweighs the smaller size of the plants.
The smaller size is productive, skipping several weeks of the vegetative phase and starting flowering much earlier than normal. This maximises the overall volume of crops in relation to the time and makes full use of the cultivated area.
Start-up of SOG
By far the most efficient way to cultivate SOG is by using cuttings/clones (as opposed to plants sown from seed). Cuttings are genetically identical from the parent plant, and therefore will develop more uniformly, as well as mature for harvest simultaneously. This is a huge advantage in SOG.
It is of course possible to mix different cannabis strains or seedlings of the same strain, but this easily becomes counterproductive chaos. It will almost certainly create a lot of unnecessary challenges in terms of. different plant structures, heights, flowering times, fertilisation needs and many other factors. All this is time-consuming, mega-tedious and will inevitably reduce the overall yield of the cultivated area.
Mother plant and number of plants
First you have to find a mother plant. It is selected on the basis of desired characteristics, which are typically low height, compact structure, short flowering time and, last but not least, high production of top shoots. These are all attractive features of SOG.
The number of plants perm2 depends on several factors, as well as your needs. 16-25 plants perm2 is usually a good number. So 4 rows of 4 plants = 16 or 5 rows of 5 plants = 25, so they fit square to 1x1m.
It is a good idea to take more cuttings than you need. For 16 plants, for example, you should make 30 cuttings. That way you have a solid selection to go on. Of the 30 cuttings, take the strongest and healthiest, as well as those that have grown most homogeneously. The surplus plants are discarded.
Irrigation of SOG
The smartest solution for SOG cultivation is clearly automatic irrigation. This means that plants are watered automatically with a pump from a water reservoir (plastic tub or barrel) with a fertilizer solution. Irrigation can be continuous or at fixed intervals if connected to a timer.
The most popular choice is drip irrigation, which is both cost-effective and easy to set up. In this way, all plants receive exactly the same amount of water and fertiliser – provided it is set up correctly, of course – which increases overall production and ensures homogeneous growth.
Another popular choice is the ebb and flow system.
Pot sizes for SOG
Each plant must have its own pot.
Prior to flowering, it should be repotted 1-2 times (from smaller to larger pots).
The final pot size depends on the soil and how big you want the final plant. Transplanting saves space in the vegetative phase, as well as helping to keep plants smaller and develop a more compact structure (and ultimately providing a better yield).
For coco coir, a pot size of 3-4 litres is good. For soil/sphagnum, you need larger pots, so 5-7 litres is suitable.
With textile pots/airpots, you should go up a little in pot size – especially if you hand-wash – as they dry out significantly faster. Here, 8-11 litres is an appropriate pot size.
Pruning / plant structure in SOG
Plants in SOG should preferably have only one central top shoot with 2-3 set side branches. This is advantageous as the plant will not take up so much space and can then direct all its energy to these few top shoots, which will grow extra large and fat.
It is a good idea – and almost obligatory – to remove the lower side branches. As mentioned before, it makes the plant spend its energy on the central top shoot and the top shoots of the main side branches. This results in larger crops and thus increases the final yield at harvest time.
Pruning the lower parts of the plant also makes daily work much less difficult.
Watering, or checking all drip tubes (i.e. that they are working and not blocked for some plants), and removing dead plant material are important tasks that should be part of the daily routine.
As the plants in SOG are extremely dense and also have a compact structure, it can be frustrating and difficult to grow properly if you don’t prune. So, if you are in favour of making life as easy as possible, you should definitely do this.
Flowering and plant selection for SOG
The plants should be about 35-50 cm high at the end of flowering. Whether you choose Indica or Sativa is therefore an essential point. Since the light does not penetrate far into the plant with the SOG method, but only mainly hits the upper parts, it is important that the cannabis plant does not waste energy growing too high.
Indica strains generally grow smaller in height and more compact than Sativa strains. They are therefore generally preferable in the SOG.
Sativas also have a longer flowering time, which means they need to flower before Indica to avoid getting too big for SOG.
Good varieties for SOG cultivation
Summary: Advantages and disadvantages of SOG cultivation
+ Great returns
+ More harvests per. year
+ Lower electricity bill due to shorter growing period
– You can only run 1 cannabis strain per lamp
– More difficult to move plants around as they are very close
– Multiple plants can potentially be too confusing for the inexperienced grower
– (Requires automatic irrigation system)