Fed up with bad weather and snow, you can't wait for the next outdoor season to start. The climate in Central and Northern Europe is cold, especially in the north. That's why the official outdoor season in these regions starts in mid/late May. We have to face this fact. Nevertheless, there are some important things you can do beforehand.
Below we walk you through the whole outdoor growing year and see what there is to do in each month. The average temperatures and daylight hours mentioned are for cities like London, Paris or Bern.
Some important points
Get seeds (from us) that are especially designed for outdoor cultivation in cooler regions. Indicas and indica dominant strains have a (much) shorter flowering time than sativas, so they finish faster in summer before the bad weather sets in.
It is not mandatory, but it is advisable to grow the cannabis plants indoors before putting them outside. You can increase yields and minimise the failure rate. Get a small grow tent, a propagator or build a small grow box yourself. In the small grow box you can prepare cuttings, germinate seeds and grow plants to a certain size.
Make sure that the distance between plants and the energy-saving lamp is not too great. If you use energy-saving lamps, you can and should bring the plants much closer to the light source than with sodium vapour lamps. A distance of 10-12 cm is usually sufficient. If the distance is too great, the plants become yellowish, spidery and have difficulty standing on their own.
With our complete propagation sets, cuttings and seedlings can be conveniently and reliably grown indoors.
The environment in the house where the seedlings and small plants are grown should be well ventilated and have a fan for circulating air so that the small plants get strong thick stems. Energy-saving lamps with 100-250w have proved successful as lighting (depending on the number of plants). They need little energy and generate hardly any heat, so the fan only has to run 2-3 times an hour for a few minutes. With the energy-saving lamp you can grow the plants to a stately size until it is warm enough to put them outside.
There are basically 2 ways:
1st way: Grow indoors and bring the plants outdoors for flowering.
2nd way: Grow plants indoors, continue growth outdoors until flowering.
1st way: Grow indoors and bring the plants outside for flowering (for container plants).
From the end of March, always bring small plants outdoors at the same time and for the same duration, when there is sufficient daylight and warmth, to a place protected from the wind and sun. If there is not enough light, or if there is too much wind or rain, the plants are placed under the energy-saving lamp in the grow box as a substitute. When it is assumed to be sunny for 9 hours a day in spring, the plants are taken outdoors and for the remaining 3 hours they are then placed under the energy-saving lamp (indoors), so that we arrive at a sufficient daily lighting time of 12 hours. The plants will then start to flower with a daily lighting time of 12 hours with energy-saving lamp and sunlight outdoors for hours at a time.
It must be prevented that the plants stay too long (too many hours per day) under sunlight and energy-saving lamps. They would then fall back into the vegetative phase. This would delay the entire development period and significantly delay the harvest. If the temperatures outside are high enough and the daily hours of sunlight are sufficient, the plants can be brought outside for 12 hours a day and illuminated with sunlight. After exactly 12 hours, the plants must be brought into the absolutely light-proof and well-ventilated grow box. In the morning and always at the same time, the plants are brought back to their sunny place outside.
The disadvantage of this method is that it is time-consuming and requires a lot of time. The plants always have to be brought outdoors and indoors at the same time. Plant containers have to be dragged.
The big advantage is that you don't have to wait for what feels like an eternity, even in Central and Northern Europe, until you can enjoy the first outdoor buds of the season.
This method can only be used with container plants.
2nd way: Grow plants indoors, continue growth outdoors until flowering.
This method of outdoor growing involves germinating seeds indoors and growing the seedlings indoors into robust plants. The cannabis plants can either be planted/put outside as soon as the number of daylight hours and temperatures are sufficient, or you can wait until the end of June to bring them outside. This is when there are the most hours of light per day. The cannabis plants will continue to grow outdoors for a few more weeks until they start to flower.
The two methods refer to photoperiod cannabis strains. With autoflowering/automatic strains, you don't need to worry about the daily lighting time or premature flowering. They will flower regardless and can be moved outdoors as soon as there is no more frost.
February:
- the average duration of the day is 9 hours and 21 minutes up to 10 hours and 50 minutes.
- the average temperature is 9° to 2° C.
Iceland:
- average daily duration 6 hours and 53 minutes.
- average temperature: 2° to -2° C
Around Paris and Bern it is still cold, sometimes icy or snowing. Once you have prepared your indoor grow box and ordered the seeds, you can start thinking about germinating seeds. You can find important tips here.
For growing indoors, you can use an energy-saving lamp with 100-250W. A stronger light, e.g. an NDL with 150-250W produces stronger plants and accelerates growth.
In most northern parts of Europe, soil preparation for the next outdoor grow can start at the end of February. If you live very north or in Iceland, you will have to wait a little longer. The soil is loosened, weeds and all other plants are removed. In addition, Bat Guano, worm manure and humus are mixed in. These additives need some time in the soil before they can be effective for plants. Now is the right time to put them into the soil.
March:
- the average duration of the day is 10 hours and 53 minutes up to 12 hours and 40 minutes.
- The average temperature is 4° to 12° C.
Iceland:
- average daily duration is 9 hours and 55 minutes up to 13 hours and 11 minutes.
- average temperature is -1° to 3° C.
The days are slowly getting longer and the temperatures are rising. This is exactly what cannabis plants need to grow big and strong. In some parts of Central and Northern Europe, it's not long before the outdoor growing season can begin. If you haven't bought seeds yet, now is the time to do so. Choose genetics that suit you and have a short flowering time.
If you want to prepare clones for your outdoor grow, the end of April is a good time to do it. In March, seeds for outdoor growing can be germinated indoors. Even though in many parts of Central and Northern Europe the sunlight is not yet sufficient and it is still cold, the cuttings and seedlings can be placed under artificial light indoors to replace the missing light and avoid early flowering.
April:
- the average length of the day is 12 hours and 45 minutes up to 14 hours and 25 minutes.
- the average temperature is between 5° and 16° C.
Iceland:
- average daily duration is 13 hours and 18 minutes up to 16 hours and 30 minutes.
- the average temperature is between 1° and 6° C.
Pre-grown cannabis plants can go outside as soon as the temperatures and light hours per day are sufficient.
It is spring and the hours of light per day are constantly increasing. By the middle of the month, the light hours per day are at least 14. As soon as the days are long enough, artificial light is no longer needed, unless you live in an area where it is still very cold and therefore prefer to keep the plants indoors for a while. Prepare all the equipment, the appropriate fertiliser, plant pots, soil additives, watering accessories and everything else you need for further outdoor growing.
At the end of the month, it is safe to bring the cannabis plants outside and cultivate them outdoors in almost all northern European countries. Only at night can it still get very cold or even frosty in some regions. Then you should bring the plants inside at night. In the sunlight, the small pre-cultivated plants now grow visibly and become taller.
If you live in Iceland, you will have to wait a few weeks before you can put the cannabis plants out. Or you have a greenhouse to protect the plants from the cold.
April is a good time to take some nice cuttings from a mother plant and root them for outdoor growing. April is also a good time to germinate seeds if you haven't done so yet. If temperatures allow, the small plants can grow outdoors until they are big enough to be placed in the next larger planter or planted directly in the ground.
If you put the plants directly into the ground in the wild or do a guerrilla grow, you should protect the small ones from wild animals with a fence or chicken wire. Deer, rabbits and mice love the taste of cannabis and can destroy a whole plant or several in a short time. Hare wire fencing is cheap, very unobtrusive and easy to shape. Plants planted directly into the ground should be given a large enough planting hole, filled with an organically enriched soil mix. Here is a recipe for an organic soil mix. If the soil is enriched with additional organic nutrients and additives months and weeks in advance, it is no longer necessary to fertilise the plants every time they are watered. Irrigation systems can be conveniently brought into use.
Important organic additives for a soil mixture can be:
- Powdered dolomite
- Algae powder from various dried algae
- Guano/Bat Guano
- Seabird Guano
- Palm ash
- Worm dung
- Humus etc.
Avoid waste products from factory farming such as: Blood meal or bone meal, it is not really what a grower should use and can also contain pathogens.
You can find out more about organic additives for soil enrichment here:
- Homemade compost for outdoor growing
- Organic cannabis cultivation: mix your own soil
- Organic fertilisers and additives in cannabis cultivation
May:
- the average length of the day is 14 hours and 28 minutes up to 15 hours and 48 minutes.
- the average temperature is 8° to 19° C
Iceland:
- average daily duration is 16 hours and 36 minutes up to 19 hours and 49 minutes.
- the average temperature is 4° to 9° C.
Spring is clearly showing itself. Outdoor growing can start. You can also start in Iceland if you take the night frost into account and bring the plants in better at night.
In very northern and cold regions like Iceland, you may want to consider growing autoflowering varieties outdoors. These will be ready before the first and early frost sets in. This way you can get good yields even in cold regions.
The young cannabis plants will become bushier, gain height and probably need to be placed in larger planters if you are growing in containers.
Check the plants, leaves (+ undersides of leaves) several times a week and take action if you notice any changes or abnormalities. Like You recognise pests and Fix problems you can find out here.
June:
- the average length of the day is 15 hours and 50 minutes up to 16 hours and 9 minutes.
- the average temperature is 11° to 22° C.
Iceland:
- the average duration of the day is 19 hours and 54 minutes up to 21 hours and 1 minute.
- the average temperature is 7° to 12° C.
Summer begins in Central and Northern Europe. The plants will develop excellently this month and show rapid growth. Both feminised photoperiod plants and automatics enjoy the large amount of light and the higher temperatures.
21 June is the longest day of the year!
If you bring your plants outside at this time and continue growing outdoors, you can also achieve very good yields and avoid problems with premature flowering or a relapse into the vegetative phase. The plants continue to grow for some time, get the best light of the year until they notice that the days are getting shorter and finally flowering starts. However, this only happens later in the summer or autumn.
Keep checking the plants for pests, diseases and changes and take action if you notice anything. It is better to use natural and organic pesticides such as neem and cinnamon extract and avoid chemical pesticides if possible.
July:
- the average duration of the day is 16 hours and 08 minutes up to 15 hours and 15 minutes.
- the average temperature is between 13° and 25° C.
Iceland:
- average daily duration is 20 hours and 57 minutes up to 15 hours and 15 minutes.
- the average temperature is 8° to 13° C.
This month and the next are the hottest of the year. You can also see this in the plants. If you planted automatics in spring, they may well be ready now and have nice buds. The first feminised plants will grow hairs. If you have grown regular seeds, it is time to pay attention to when the first male plants appear. About 2 months after germination, the plants will show their gender.
August:
- the average length of the day is 15 hours and 12 minutes up to 13 hours and 31 minutes.
- the average temperature is between 13° and 25° C.
Iceland:
- the average length of the day is 18 hours and 12 minutes up to 14 hours and 55 minutes.
- the average temperature is 8° to 13° C.
If you have germinated autoflowering seeds in May, now is the time to harvest the automatic plants. First remove the big leaves and then the smaller ones. The branches or the whole plant with the flowers are taken to a dry and dark place and slowly dried over 10-14 days. Afterwards, the dried buds can be stored in glass or stainless steel containers and consumed.
At the end of this month, most European countries will have less than 14 hours of daylight. At this time, the photoperiodic plants (from regular seeds) will enter their final phase, namely the flowering phase.
September:
- the average duration of the day is 13 hours and 34 minutes up to 11 hours and 52 minutes.
- the average temperature is 11° to 22° C.
Iceland:
- the average duration of the day is 14 hours and 49 minutes up to 11 hours and 41 minutes.
- the average temperature is 5° to 10° C.
The feminised cannabis plants will increasingly produce buds, hairs and trichomes during this month. The plants should be kept dry during this time and protected from too much wetness, e.g. with a tarpaulin or a plastic roof. If necessary, heavy branches with large flowers are supported with the help of planting sticks. This is to prevent wind or rain from breaking branches and flowers.
Autumn begins this year on the 23rd. The transition is slower in Nordic countries like Iceland.
October:
- Average daily duration: From 11 hours 48 minutes to 10 hours 04 minutes.
- Average temperature: 9ºC to 18ºC.
Iceland:
- Average daily duration: 11 hours 36 minutes to 8 hours 21 minutes
- Average temperature: 2ºC to 6ºC
Autumn has begun and many outdoor plants have blossoms. In France, Great Britain or even Norway there is plenty of rain. Special attention must be paid to mould in the flowers (Botrytis). If a fungal disease appears on a plant, quick harvesting must be considered because fungi can spread quickly and easily and render the entire crop useless. In mid-October, many Indicas and Indica dominant varieties can be harvested.
November:
- Average daily duration: 10 hours 01 minutes to 8 hours 40 minutes
- Average temperature: 5° C to 11° C
Iceland:
- Average daily duration: 8 hours 15 minutes to 5 hours 18 minutes
- Average temperature: 0° C to 3° C.
Only the bravest are still growing outdoors this month. If you have planted a sativa strain, you may be lucky enough to harvest it this month. In a greenhouse, the chances of you getting a good harvest from a sativa increase significantly.
In November, the harvested cannabis plants are dried and manicured and stored for later use. The quality of the cannabis depends crucially on the correct drying process. In "Drying cannabis properly" you can find out more.
December
- Average daily duration: From 8 hours 39 minutes to 8 hours 17 minutes
- Average temperature: 3ºC to 8ºC.
Iceland:
- Average daily duration: 5 hours 13 minutes to 4 hours 16 minutes
- Average temperature: -2° C to 2° C.
December is the time to enjoy the results of the Last Harvest and try out creative smoking utensils.
It is very cold and in countries like Iceland there are hardly more than 4 hours of light. The perfect time to enjoy your own grass, watch films together and have conversations. You realise you did your job well at the last outdoor grow and can relax.
January:
- Average daily duration: 8 hours 18 minutes to 9 hours 20 minutes.
- Average temperature: 22ºC to 8ºC.
Iceland:
- Average daily duration: 4 hours 20 minutes to 6 hours 47 minutes.
- Average temperature: -2° C to 2 ° C.
This month is very cold and icy. The best thing outdoor growers can do now is relax and plan their next grow. It's time to browse our grow encyclopaedia for details, look at different strains and think about a possible suitable grow site for next season. There is always something new to learn.
You might be interested in: Protecting cannabis plants from the weather.