Follow this month-by-month guide to grow a crop of healthy and productive cannabis plants outdoors in the UK in 2022. Farm. Food. Life.
Growing Cannabis Outdoors In The UK: Month-By-Month Guide 
Don’t let the heavy rain and seasonal humidity put you off. It’s perfectly possible to raise a healthy and vibrant crop of cannabis plants outdoors in the UK. Follow our in-depth guide below to find out how.
Cannabinoids, terpenes, phytochemicals, organic cultivation
A complete month-by-month guide to growing cannabis outdoors in the UK.
- Growing cannabis outdoors in the uk in 2022
- Is weed legal in the uk?
- A guide on growing cannabis outdoors in the uk
Growing outdoors comes with a unique set of challenges per location. Everything needs to be considered, from local pest species to the best strain for the job. Simply follow the growing guide below to boost your chances of a successful outdoor harvest in the UK.
GROWING CANNABIS OUTDOORS IN THE UK IN 2022
Growing cannabis outdoors in the UK usually involves (at least) one consistent weather condition: rain! Your plants will rarely go thirsty or wilt from the heat. The UK experiences a temperate climate defined by cool, wet winters and warm, wet summers. The country rarely experiences extreme weather events, although flooding and droughts do occur from time to time. The UK sees an average of 133 days of rain and around 1,350 hours of sun per year. This fine balance of rain and sun gives plants plenty of the key resources to develop properly.
The UK features four climate segments:
• South-east: This region experiences cold, biting winters along with warm, dry, and pleasant summers. Continental winds keep things relatively dry in general. South-east UK encompasses London, Brighton, Cambridge, and Norwich.
• South-west: This area of the country sees mild and very rainy winters contrasted by warm and wet summers. Tropical winds from the south extend the growing season. Includes Cornwall, Devon, Bristol, and Cardiff.
• North-west: The north-west experiences mild winters and cool summers. Maritime winds bring a whole load of rain all year round. This region covers Northern Ireland, northern Wales, and western Scotland.
• North-east: Arctic winds from the north bring cold winters, cool summers, steady rain, and a shorter growing season. Includes Newcastle, York, Edinburgh, and Aberdeen.
IS WEED LEGAL IN THE UK?
Unfortunately, the United Kingdom is lagging behind more progressive European nations when it comes to cannabis legislation. The government categorises cannabis as a class B substance, meaning mere possession can lead to a maximum 5-year prison sentence, an unlimited fine, or both. Growing and supplying cannabis can lead to the more extreme punishments of up to 14 years in prison, an unlimited fine, or both.
Despite the draconian nature of UK cannabis laws, things are improving. CBD products are widely available over the counter in stores, so long as they possess no more than 0.2% THC. The government also allowed doctors to start prescribing cannabis products to patients in 2018. In 2019, the NHS received the all-clear to start prescribing cannabis-based products for Lennox–Gastaut syndrome and Dravet syndrome.
The UK has a long way to go to match the more relaxed approaches of certain American states and European nations.
A GUIDE ON GROWING CANNABIS OUTDOORS IN THE UK
Below, we’ll generalise and focus on the south-east, south-west, north-east, and north-west, while touching on specific locations along the way. It’ll help if you do a little more research on your specific area just to make sure you have all the bases covered.
• Day length March 1st: 10h 57m
• AVG temperature: 3–10°C
March marks the official start of spring. However, things are still pretty chilly in most of the country. But this doesn’t mean growers can’t get a head start indoors. Start germinating your seeds and placing emerging seedlings under LED lights or on a sunny windowsill.
Start weeding your beds and dressing them with high-quality compost. Layer them with straw or wood chip mulch to trap moisture and prevent weeds from returning. If you’re growing in containers, dress them with good compost, too. Start cleaning out and preparing your polytunnel or greenhouse, if you’re lucky enough to have one. Scrub down any algae from the glass panels, brush out debris, and get it ready to host your cannabis plants in the coming weeks.
Certain microclimates around the UK allow lucky growers to plant outside during March. Cultivators in the Scilly Isles, Anglesey and Dungeness usually see the last frost around late February.. Pay close attention to the forecast and decide whether the risk might pay off. Make sure to keep a backup crop growing indoors just in case.
• Day length April 1st: 12h 59m
• AVG temperature: 5–13°C
April brings a significant improvement in weather and sunlight. Bluebells, wild garlic, and other aromatic spring flowers lead the charge of emerging plant life. Although April brings a nice, warm heat, frost still poses a significant risk. Growers in most regions will need to keep their plants indoors under lights and on windowsills for a couple more weeks to be safe. However, cultivators with greenhouses or polytunnels will be able to safely move their plants to these structures during April.
Only water your seedlings when the top inch of soil dries out, being careful not to overwater. Head out into the garden and keep the “bad weeds” under control. You’ll be able to sow hardy companion plants during April, such as peppermint, yarrow, coriander, and marigold. These plants will start flowering in the coming months, helping to distract pest insects and attract beneficial ones. Take a stroll around your beds, look out for weeds, and remove them by hand if you stumble across any.
How to Grow Cannabis In Your Garden
With weed well on its way to being legal, it’s high time we talk about how to grow the stuff in your garden.
With weed well on its way to being legal, it’s high time we talk about how to grow the stuff in your garden.
The federal government still considers it a crime to grow or possess cannabis, but 30 states have now legalized it to varying degrees. Washington, Oregon, California, Alaska, Nevada, Colorado, Maine, and Massachusetts have decriminalized weed for recreational use, and similar legislation is under consideration elsewhere. Pardon the pun, but it is high time we talk about how to grow the stuff.
The old-fashioned way – outdoors – is easiest. The trend towards indoor cultivation is more a product of, one, a desire to hide what you’re doing (no longer necessary in many locales); and two, to exert total control over growing conditions for the sake of producing enormous buds with maximum market value. But if your sole goal is just to have a bit of decent weed around to occasionally enjoy, you may as well plant it alongside your zucchini and basil.
Growing a successful cannabis crop is a bit more complicated than your average vegetable, but not much. Before you get carried away, familiarize yourself with your local laws – NORML provides a comprehensive list here . Horticulturally speaking, here’s what you need to know.
Plenty of mail-order firms have sprung up to fill the demand for legal plant material. There are thousands of varieties, with all the trippy descriptions you would expect. If you want a cerebral high and non-skunky citrus flavor, there is a breed for that; if you want something that is good for anxiety, low in THC, and grows less than 3 feet tall, you can find that too.
Most importantly, purchase seeds for varieties suited to outdoor conditions, rather than those bred for indoor grow operations. Any reputable supplier will specify that information in their varietal listings. Most will also note mold-resistant varieties, which are a wise choice in humid regions, as well as those with a “short flowering period,” an important consideration in northerly latitudes (this is akin to the “days to maturity” listed on packets of vegetable seed).
Understanding Male and Female Plants
Cannabis is one of many species in the plant kingdom that produce male and female flowers on separate plants. Females produce fat flower “buds” rich in psychoactive compounds, while male plants produce spindly little flowers that aren’t worth smoking (or however you choose to partake).
When you plant cannabis seeds, you typically end up with about half male plants and half female plants. It is imperative to get rid of the males before the plants begin to flower, as the male pollen will result in female buds that are full of seeds, which is no good. It’s not that hard to determine the sex of cannabis seedlings – you can find instructions here – and cull the males.
But it can be even easier! How? Look for varieties labeled “feminized.” These are seeds that have been bred to produce only female plants and are highly recommended for novice cannabis gardeners.
Another option is to purchase “clones,” which are rooted cuttings of female plants. This is essentially like buying vegetable seedlings, rather than seeds, which saves you the time and effort required for germination, along with the trouble of weeding out the males.
Weed seeds require no special treatment, though they’ll germinate faster if you soak them in water for a few days before planting. As with tomatoes and other heat-loving vegetables, you’re better off starting the seed indoors in a sunny window in early spring, and then transplanting the seedlings outdoors once all danger of frost has passed.
To do well, cannabis plants require a minimum of six hours of direct sun each day and excellent drainage. They’ll do fine in a typical raised bed like you’d use for vegetables, though five-gallon pots filled with potting soil also work well for pot (hard to resist the punny wordplay!). Good air circulation is critical for preventing fungal diseases, so space the plants at least six feet apart (closer is ok for dwarf varieties) to ensure that they don’t resemble a dense hedge by the end of summer.
Cannabis plants love their nutrients, so plan to enrich the beds with composted manure, ideally at least one month prior to planting, if not the previous fall. Spread a minimum of 2 inches of compost over the planting area and work it into the soil. If planting in pots, you can rely on fertilizer, rather than compost.
Feeding and Watering
This crop is also a thirsty one, so be sure to irrigate whenever the surface of the soil becomes dry. Adding a layer of mulch once the plants are knee-high will cut back on the loss of soil moisture through evaporation and help to prevent other “weeds” from getting established in your weed planting.
If your beds are sufficiently rich, fertilizer is not required, though it will lead to better results (it’s a must for potted plants). Apply a high-nitrogen fertilizer every three weeks until mid-summer, as this will stimulate abundant vegetative growth. Then switch to one higher in phosphorus to stimulate dense and abundant flowers (buds).
Depending on the variety, outdoor plants can grow 12 feet or more in height. Most growers prune them, which makes the plants easier to manage and results in far more buds. Professional growers have perfected pruning to a fine art for the sake of maximizing yield, but for the casual grower is sufficient to cut back the most vigorous shoots from time to time. Simply clip off the outer 30 percent of each major shoot every few weeks.
Pruning encourages a bushier form (rather than a tall, spindly plant) by stimulating the growth of numerous small side shoots, each of which will produce additional buds. Just be sure to stop pruning by mid-summer, so as not to interfere with flower production.
Buds will begin to form in late summer and should be ready for harvest during the month of October. You’ll know they are ready when the flower pistils – those wispy hairs that emanate from the buds – turn from white to reddish-brown.
Cut the buds from the plants, leaving 6 or 8 inches of stem below each one, and trim off all the leaves. Hang them from their stems to dry in a warm, shaded place for about a week. The weed is now ready to use. Trim the buds from the stem and store in a glass jar.