Growing marijuana on terraces

How to grow marijuana for personal use on your balcony

Growing marijuana outdoors – and specifically on balconies – is one of the most popular systems because it takes less effort, means and care than growing cannabis indoors. Also, this way you can get a good yield with minimal investment.

The most important thing to take into account to get best results is the availability of a terrace with high solar exposure, i.e. a minimum of six hours of direct sunlight every day. In addition to this essential requirement, the other stuff you will need is:

  • Quality seeds, preferably indica or indica/sativa strains, as they are usually bushier and have more compact structure. Using feminized cannabis seeds or selected cuttings is also useful, for this allows us to optimize the available space and ensure that you take full advantage of the soil, pots and any other farming gear used.
  • 0.25 litre, 11 litre, 25 litre or 45 litre pots (the largest pot size is only suitable for growers who have large terraces, the rest will have to use the first three ones).
  • Quality soil, containing vermicompost, mulch, perlite and black peat or coco coir (coconut fibres). The type of soil should be similar to Biobizz Light Mix or Bioaigua Soft Mix.
  • Vermicompost (worm humus).
  • Bat guano, powder and liquid bat guano.
  • Nutrihemp (seaweed extract).
  • Neem oil, pyrethrum or any other organic insecticide such as Ain thc.
  • Propolis (a fungicide and a stimulator of plant defences).
  • Bacillus Thuringiensis.
  • Fertilizer for cannabis growth and flowering (preferably organic).
  • A small sprayer (2 litres).
  • A pH tester and pH down acid reducer.

Cultivation of cannabis on terraces step by step

This plant has just been transplanted into a bigger pot.

This plant has just been transplanted into a bigger pot.

Once you get hold of all the needed materials, you can start growing!!

The best time to start the crop on the balcony is between April and May. We prefer doing it during the first waning moon of May, since if we do it earlier, plants will probably grow too tall and exceed the capacity of the pots.

First, we need to germinate the seeds. Once we see the small roots coming out we transfer them to a 0.25 litre pot and water them. During the following days, we will water the plants as the soil dries out (use pH=6 water). Place the pots under direct sunlight and the small seedlings should spring within 5-10 days; otherwise, the plants will grow too tall and will be too weak and lanky.

After about three weeks, plants should reach 20 cm in height and three sets of true leaves should have appeared. At this time, remove the plants from their pots (when the soil is dry) and, if there is a good root structure, it will be the right time to transplant them to the 11 L pots.

Transplant to a 11 litre pot

Transplant to a 11 litre pot

In this case, make the following blend:

  • 80% of the recommended soil
  • 20% of vermicompost
  • 1/2 kg of bat guano powder
  • 250 grams of nutrihemp per 100 litres of soil

Mix it thoroughly to blend it evenly and proceed to transplant.

The first two weeks after the transplant, water the plants whenever the soil is dry with tap water, only adding the needed acid to reduce water pH to the right value.

By the third week after transplanting, you should start adding – once a week – the corresponding dose of growth fertilizer to the water.

25 L pot, two weeks after apical pruning

25 L pot, two weeks after apical pruning

Around the fourth week after transplanting, (eight weeks after the start of cultivation, i.e. early June) apical pruning is done to encourage horizontal growth rather than vertical. You should proceed as follows:

The plant should have produced its seventh or eighth pair of true leaves; trim the apex (the top sprout) just above the fifth true pair of leaves, which will enhance the growth of six to ten new main branches.

Right after pruning, do the final transplant to a 25 litre pot – for those who don’t have much space – or to a 45 litre pot, in the case you have more room for the plants to develop.

One week after apical pruning in a 45-50 L pot.

One week after apical pruning in a 45-50 L pot.

For the final transplant, the potting mix will be the following:

80 litres of used soil + 20% vermicompost + 1/2 kg bat guano +200 grams of Nutrihemp per 100 litres of soil.

After the transplant, flush the plants with tap water for the first two weeks, and after the third week add fertilizer for growth to the water once a week until the onset of the first buds. This will be around August and our plants will be between 100 and 125 cm tall (excluding the pot).

The plant is shaping up nicely.

The plant is shaping up nicely.

Horizontal growth with the help of ropes, LST technique.

Horizontal growth with the help of ropes, LST technique.

Apical pruning of cannabis plants without using ropes.

Apical pruning of cannabis plants without using ropes.

Cannabis plant side branches.

Cannabis plant side branches.

Marijuana crop in mid-July.

Marijuana crop in mid-July.

Marijuana crop.

Marijuana crop limited in height.

A uniform cannabis crop.

A uniform cannabis crop.

When the first flowers appear forming buds, water them with water and flowering fertiliser once a week (the rest of irrigations should be done with tap water with adjusted pH). When you see that the buds are shaping up, add liquid bat guano to the nutrient mix, and then increase the frequency of fertilisation to twice a week, until you see the first signs of ripening in the buds (pistils get dry and turn brown-reddish).

Then, start watering with tap water until harvest to clean the plant and improve its taste and smell. If the plant turns yellow during the cleaning process, it’s fine, as we want the plant to use its own nutrient reserves. In this way, it will be sweeter and it won’t be too aggressive for your throat when you somke it.

Night view of a marijuana crop on a terrace.

Night view of a marijuana crop on a terrace.

Harvest is approaching.

Harvest is approaching.

When 80% of the pistils of the buds are dry it will be the right time to harvest. However, if you want to be sure, the best option is using a magnifying glass or a microscope to examine the state of ripeness of the trichomes.

For more information on this subject, visit our post: When to harvest marijuana plants .

Marijuana plants about to harvest.

Marijuana plants about to harvest.

The plants grown in 25 litre pots will reach a height around 100-150 cm, depending on the strain, and will give a yield between 200 and 300 grams (of dry buds), while cannabis grown in 45 litre pots can grow up to 125-175 cm in height and produce a yield between 300 and 500 grams, depending on strains and phenotypes.

Aspects to consider when growing cannabis on terraces:

  • If the sun shines directly on our potted plants, roots can reach 40°C, which is not advisable. To avoid this we can use white pots and protect them from the sun by using other plants or any other thing as shading protection which can help reducing the contact with direct sun and therefore lowering the temperature of the soil/roots.
  • It is advisable to grow other plants (flowering or leafy plants) on our terrace in addition to marijuana, as they will help creating a suitable microclimate and enhance biological richness in the environment, as well as helping us to camouflage our secret garden.
  • If our terrace is very sunny and gets very hot during the day, it is highly desirable to wet the terrace floor and walls in the mornings and evenings, as well as refreshing the leaves of our plants long before the flowering stage begins, especially in June and July, which is the peak of the red spider pest.
  • If the terrace is very exposed to the wind, we must use ropes, stakes and stones to tie the plants and prevent them from falling or breaking.

Phytosanitary treatments outdoors

Outdoor crops are exposed to numerous pests, so you should do periodic treatments that will prevent the use  of chemical insecticides later on. Chemical treatments are a lot more toxic and harmful for our health, and for our family and pets.

Start pest control treatments when you transplant the plants to the 11 litre pot, using neem oil or a pyrethrum-based insecticide mixed with propolis to avoid red spider mites, whiteflies or aphids, as well as the various types of fungi that affect cannabis.

The treatment should be applied every 15 days until the end of July, at which time we will begin the next treatment, spraying with Bacillus thuringiensis (to avoid the appearance of dangerous caterpillars) which should be alterned with another treatment based on propolis to prevent powdery mildew. Continue doing these treatments until two weeks before harvest.

It is important to carry out all treatments as well as watering and transplanting early or late in the day to avoid strong heat, as it could damage the plants. 

We wish you happy growing for the new season!

November 24, 2014 | Outdoor cannabis growing
5 Comments


5 comments on “Growing marijuana on terraces

  1. Guest

    Very nice article very detailed but you didn’t cover Autoflowring plants. As they do not like transplant so suggest a soil mix (not commercial) for the same. please suggest homemade potmix from seed to harvest for 20L pot for autoflower as well as photoperiod.

    1. Dani Alchimia

      Hi Guest,

      If you want further information about autoflowering plants, you can read this article.

      Thanks for your comment,

      All the best!

  2. Billy

    Great article, and lovely pictures. What about the smell? Doesn’t it reek when they are flowering, and with so many plants or top colas. I bet you can smell that cheese a mile away, no? Please share your thoughts.

    1. Dani Alchimia

      Hi Billy,

      That’s correct, the main disadvantage og growing in a balcony is the intense smell of the plants when they’re in bloom. Unless you have cannabis-friendly neighbours it is always better to grow indoors.

      All the best!

  3. GrowingMarijuanaTips.Com

    I’ve never thought that marijuana makes a nice night plant. I mean look at those buds! They seem like to glow in the dark. Beautiful!

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