What is 'Guerilla Growing'?
Guerrilla growing is essentially cultivating cannabis secretly in an outdoor location; this is normally in the wild and stealthy, as you want to ensure nobody will discover your plants.
That means no busy public parks or well used pathways but somewhere like a clearing in a forest can make a perfect grow site.
Where to put your grow spot
To avoid anyone finding your plants and stealing or destroying your plants, make sure to not plant in a location close to where people will be; these are more easily discovered by passers-by, since the odour of the grow will be noticeable up to 10-15 metres away.
Forests, fields, and abandoned farmland make good potential locations. You can choose to grow directly in the ground or in fabric pots (so, if needed, you can move your plants around).
Bear in mind that the vegetation around the grow site will likely change with the seasons so try and envisage what the site will look like in mid-summer.
Also really important is that you must make sure there are no streetlights in the vicinity as these could otherwise mess up your plant’s natural dark cycle, negatively impacting flowering.
We advise growing a few plants in some different places; if one of your crops is discovered, the others will still be hidden – i.e., don’t put all your plants in one basket!
If your grow site is close to water that is a massive bonus as you can easily water your plants in case of a drought rather than lugging heavy buckets/ bottles of water around.
It may even be possible that you won’t need to water your cannabis plants at all as your plants may be able to absorb the water that’s already in the soil. A spot close to running water is also at less risk for frost – but may be more at risk of flooding.
Timing your Guerilla Grow
Timing is super important: plant too early, and your weed may fall victim to cold temperatures and frost. Plant too late on the other hand, and it may succumb to mould from the autumn rain.
If you’re growing photoperiod cannabis, timing is especially crucial. You want to make sure your plants have a decent veg time, as well as enough time to fully mature their buds before harvest.
Since photoperiod strains flower based on available light hours, you’ll need to make sure they’re ready to do so when the time comes.
The best time to head outside depends on your local climate.
Obviously, someone in a colder region, such as the UK or Germany, will be more limited in their window than someone in, say, Italy or Spain.
Start off seedlings inside
For a successful guerrilla grow you will want to choose the strains that are best for outdoor growing; these can either be a good, mould resistant photoperiod or more common these days are autoflowers (their short height and limited lifetime is a good way to minimise the risk of detection and of mould setting in).
Wind and weather, cold and hot temperatures, and pests make a cannabis plant’s life challenging enough. Unfortunately, seedlings are particularly vulnerable in uncontrolled environments outdoors.
You can make it much easier for your plants by germinating seeds at home and then allow them to develop into healthy little plants of up to 30cm before you set them outside. If at all possible, slowly acclimatise them to the outdoors by putting them outside for 2-3 hours at first.
Preparing your grow site
If you’ve found a secluded spot, but the quality of the soil isn’t great (very loamy, dark, and rich-looking) it’s not the end of the world – you can improve it by adding some potting soil and coco coir or even better, by adding professionally made super soil, as well as organic amendments.
This should have perlite/ vermiculite or lava rock for aeration and to hold onto moisture.
To achieve the best marijuana yields you will benefit from adding at least 20L of a good super soil such as the ones developed by Living Soils. You can choose which one depending on whether you’re growing auto-flower or photoperiod plants.
Out in the wild your plants will be susceptible to cannabis-loving animals such as deer, rabbits, ants, mites, or slugs.
In Northern climates in particular it’s a great idea to use a slug barrier and employ other preventative measures like predator urine or neem oil to keep pests away. It’s also good to set up protective cages for your plants with chicken wire & bamboo canes (if your site is in an exposed location).
Planting your seedlings
Once frost is no longer a threat, it is time to plant your seedlings in their new home. Take your pots to your grow site, remove the plastic before placing them in the ground. If you are inclined to keep it a little greener, use pulp pots—they are biodegradable and can just be thrown away.
Plant Maintenance
In a perfect world, you’d just plant your seeds, and after some weeks go back and harvest. If only it were that easy! Instead, you’ll want to check on your plants often as they grow along.
Aside from watering them, you’ll need to inspect for pest infestations and give them nutrients.
Dry amendments from Living Soils are the perfect choice for the guerrilla grower as they are:
Slow release – no need to amend the soil at your grow site often (just use the feeding schedule for a 20L pot in soil)
Light – you don’t have to carry big bags/ heavy bottles of liquid fertilisers around
Compostable – so you can just dig a hole around where the grow site is and know that the packaging will degrade over time.
As autumn approaches, you’re advised to add some special flowering nutrients to maximise your yield and is the perfect time to sprinkle some Bloom2 (or Bloom AUTO for auto-flowers) around the base and water in – these dry amendments contain phosphorus and potassium, which your ladies will need to fatten their buds.
Which strains love the UK climate?
An outdoor cannabis grower on the English south coast will face a different set of challenges to a grower in Scotland. The UK has a variable and an unpredictable climate. Some growers will be able to fully bloom a photoperiod outdoor strain such as Frisian Dew, whereas guerrilla growers further north may be better advised to stick to autoflower strains which are faster to finish and perhaps more likely to deliver a harvest.
Conditions, temperatures and light hours vary from one UK location to the next. The following table gives an approximate guide to the environment facing many UK growers through the summer months. Note that these are just approximate averages, each UK growing season can show surprising levels of variation from year to year and also from region to region. This presents some genuine challenges to UK outdoor growers.
On top of the regional environmental variations are the normal climatic variations. Some years can produce great growing conditions with long, sunny autumns (fall).
Other years can see the UK summer replaced with a few months of cold, damp and overcast conditions. That’s why many UK outdoor cannabis growers opt for a mix of fast-finishing autoflower seeds as well as some dependable photoperiod outdoor strains. The autoflower seeds should provide a mid summer harvest even if the late-season autumn/fall weather is bad and compromises your photoperiod harvest.
One other consideration is the last frost date. Many UK growers germinate their cannabis seeds indoors and give them a few weeks of indoor light (with e.g. an 18/6 or 24/0 light schedule). The seedlings should only be planted out after the last frost date for your location. With the benefit of indoor protection during their most vulnerable first few weeks, these plants should go onto deliver good growth and harvests.
The UK Cannabis Seeds collection are all great options for UK outdoor growers. Just visit the link, and type 'UK' into the search bar. They will often grow from seed to harvest in UK conditions in around 100 days, possibly a little faster in warm and sunny conditions. With the benefit of some planning and perhaps the use of greenhouses, you may be able to get two successive outdoor auto-flower crops in one season if the weather is kind.
Many UK auto growers germinate their seeds in May and grow them indoors for a couple of weeks before planting out after the last frost. This allows mid summer harvests.
Even growers in the far north of the UK should be able to get an auto-flower harvest if they grow in their warmest and sunniest 3-month period.
Giving the seeds a week or two of indoor growth after germination is always a good way of giving your plants a head start. All the UK Cannabis Seeds auto-flower seeds would be good choices for an outdoor cannabis grower, but the following 5 strains are particularly recommended and produce great results for outdoor growers. Which strains love the UK climate?
Feminised outdoor cannabis seeds have the advantage of somewhat longer grow cycles and consequently heavier harvests (compared to auto-flower seeds) for UK growers. The growth cycle is typically around 5 months from seed to harvest with plants typically ready for harvest around late September or early October.
However, not all outdoor feminised strains will finish in time in all areas of the UK. If you get unlucky with a cold and wet UK September/October then you can lose your photoperiod harvest to mould and bud rot.
Our recommended top-5 photoperiod outdoor feminised cannabis seeds are the toughest in the Dutch Passion collection. They will finish early, and are particularly resistant to outdoor conditions. Growing cannabis outdoors in the UK
Growing cannabis outdoors in the UK isn’t that difficult. Plenty of growers harvest their entire annual cannabis requirements from just a handful of outdoor plants grown from a few auto-flower seeds or feminised outdoor seeds. One of the keys to outdoor success is to know your growing season well and plan your seed selection accordingly. The further north you are, the more likely that auto-flower seeds will be your main outdoor seed choice.
Understanding the typical dates of your last frost allows you to know when to put your plants outdoors. Knowing when the end of season weather turns for the worse is another key piece of information to allow you to plan ahead. One of the most common errors, especially by new UK guerrilla growers, is to germinate their precious outdoor cannabis seeds too early in the season.
If you need some specific help and advice on the growing season at your particular location within the UK then the following guide may help. It offers detailed cultivation advice for outdoor cannabis growers in the UK South East, South West, North East and North West. It also gives detailed advice of germinating your cannabis seeds and the best ways to start your plants indoors and gradually acclimatise them to outdoors