How to grow cannabis seeds and where you can do it?


Modified on: 10/02/2021

We explain to you how and where cannabis seeds can be grown.

Cannabis seeds, or marijuana seeds, are trendy products as they can be purchased legally online. If you’re wondering how to grow hemp seeds, you’ll find the answer to this question in the article, but first, we want to make a few clarifications.

In the UK, you can buy weed seeds online, but you cannot germinate them (unless they are light cannabis seeds that you can only grow for specific purposes). In other states, however, you can grow any type of cannabis: both high and low THC; here is where you can do it:

  • Spain
  • Austria (for therapeutic use)
  • Czech Republic
  • Chile
  • Jamaica
  • Canada
  • Lesotho (therapeutic purpose)
  • Sri Lanka (therapeutic target)
  • Several US states such as Colorado, Washington and California
  • South Africa
  • Uruguay

In most of these countries, it is forbidden to sell and possible to grow limited quantities of cannabis for personal and/or medical purposes.

However, unfortunately for us, in the UK we still have to wait. That said if you live in one of the states as mentioned above, you can proceed with our instructions on growing cannabis seeds… But if you live in the UK, take the following information only for information purposes, without putting them into practice!

How to grow cannabis seeds? Let’s start by planting them.

grow cannabis seeds outdoors or indoors

You can grow cannabis Outdoor, Indoor or Greenhouse!

There is an essential difference between planting auto flower seeds and feminized seeds: auto flower seeds are perfect for all 3 growing methods. In contrast, feminised seeds need a vast space as the plants can grow up to 4 meters tall. Therefore, feminised marijuana seeds may not be suitable for indoor growing.

That said, you should know that you can start sowing hemp in seedbeds protected from the cold as early as the end of February, while you can proceed with direct sowing in early spring. The temperatures in the seedbed must be between a minimum of 20ºC and a maximum of 25ºC. At night, temperatures should not drop below 15ºC.

Seedlings born from auto flower seeds do not like being transferred in new pots: the weed seeds must germinate in the same soil where the plants will grow. Automatic plants grow at great speed (think that they flower about 4 weeks after germination!), so a reporting would traumatise them without any chance of recovery.

We advise you to choose large pots so that the roots have enough oxygen and space: the ideal container has a capacity of 11 to 18 litres.

Read more: How to grow auto flower seeds? Our advice for an impeccable yield

Tips & Tricks on irrigation, light and climate ideal for growing hemp

Hemp is a plant that requires adequate humidity and temperatures, which must vary according to the different growth phases of the plant:

  • Marijuana seeds germination: 90% relative humidity and the ambient temperature of 20 or 25ºC
  • Plantula: 70 to 90% relative humidity and temperatures between 22 and 25%.
  • Vegetative phase: 50% relative humidity and an ambient temperature of 20ºC.
  • Flowering stage: 40 to 50% relative humidity and temperatures between 18 and 26ºC.

Read also: Seeds collection: the new trend in Europe

It is essential to maintain a constant moisture level, especially during bud birth, and the best way to water seedlings is “drop by drop irrigation”.

As far as light hours are concerned, feminised (but not auto-flowering) cannabis plants need 12 hours of light and 12 hours of darkness to flower, while auto-flowering plants have a better yield with 18/6, 20/4 or 24/24 light cycles.

An auto-flowering plant flowers regardless of the photoperiod, but an excellent yield is achieved with high amounts of light.

And speaking of light…

Growing hemp with artificial light or not?

Growing marijuana seeds with artificial light

The right amount of light is essential for hemp to flower and give you a good yield, so if you choose Indoor or Greenhouse cultivation, you should consider that you will probably need a suitable lighting system.

As you probably know, without light, there is no photosynthesis, and the plants will die. Nowadays, the most commonly used lights are HID lights (high-intensity discharge lamps), which you may also find used.

Bulbs should range from 200 watts to 1000w depending on the size of the crop.

Important: LED lights are usually the best, but prices may be too high. Consider whether or not to invest the money in this.

If you grow outdoors in a temperate climate during spring and summer, you shouldn’t have any problems with artificial lighting.

Now you have all the knowledge you need to be able to grow cannabis in a country that allows you to do so, or to have more culture about it if you live in Italy. Buy the best auto flower seeds, feminized seeds or fast growing weed seeds now at Sensory Seeds!