Successful Outdoor Cannabis Grow Guide

Finally it looks like spring has sprung and with it comes thoughts of growing cannabis outdoors.

I’m lucky enough to be able to grow a few plants each year in my garden without this being a problem, so I thought I would share my successful outdoor cannabis garden grow guide with you.

I’ve been growing my own veg for several years now, and the principles with this um .. extra special crop are much the same. But I’m aware that not everyone has this background, so here’s a walk-through of what to do to make sure it all goes well. More and more people are able to join me in the joys of outdoor grows as they get medical marijuana licenses. Its the easiest and cheapest way to provide yourself with a quantity of marijuana.

Personally I think that outdoor weed may not be strong enough for serious meds. That’s not to say I dislike it; actually I often prefer it especially for low level daytime pain relief when you don’t want to be zonked out too much. If however you need a stronger hit for specific medical conditions and treatments, I definitely suggest you also think about setting up an indoor grow room as well.

Normally I like to plant my seedlings out side in March, but as we have had two late snow showers this year, I’m thankful that I held off. Here’s my guide to a successful outdoor grow.

 Germinating cannabis seeds.

  1. Always and always, start your cannabis seeds off inside. I like to germinate my seeds on damp tissue paper, covered with another layer of tissue (or a paper coffee filter), wrapped in clingfilm and  left in a warm dark place to sprout.

Why do I do this? Well because that way I see how many of my seeds have germinated, and they get moved from ideal germination environment to ideal seedling environment only when they’re ready. Don’t ask me why, but it seems to me that if I put an individual seed in its own little pot, and line up the pots watching and waiting for little leaves, not all of the little gals make it that far.

Problems germinating cannabis seeds?

The answer is likely to be either your environment is too dry (and don’t drown them either!) or too cold. You can read more about the ideal environment for marijuana seeds here. But like I said, I use “granny’s method) and it works just fine for me.

This way normally 95% of cannabis seeds germinate within 24-48 hours. Check them on the second day and if all have sprouted their first root, carefully lift off the tissue paper (use tweezers gently) and plant into a 3” pot.  Prep the pot first by filling with a mix of specialist marijuana compost and perlite to give good drainage. Flush the pot full with pH water 6.3 then allow to drain off completely. When the soil is damp, not wet, its time to plant those precious sprouted seeds. Using a finger (if you’re mucky like me) or a “dibber” (usually a pencil) make a 1″ depth hole in the middle of the pot. Using tweezers, gently lift the seed out from the paper, and place root first into the hole.  Brush soil over the hole and tamp down firmly but gently to get rid of any air pockets in the soil.

The pots need to go into “seedling environment“. This is best done by placing them in a propagator, but this is not absolutely essential. What is important though is they get the right environment. Young plants like it humid, warm and remember not to keep your light source too far away cos if you do they’ll stretch.

A big advantage to starting your outdoor plants indoors in this way is that you are less vulnerable to the vagueries of late bad weather. No matter that we had snow here in March. My babies were pushing their way through the compost layer in the humid warm environment of their seedling bay.

The other big plus point to starting your plants off indoors is that not only are young cannabis plants vulnerable to the weather, they are also vulnerable to pests and diseases. This will be the case throughout any outdoor grow, but the sight of young tender shoots in early spring when little else may be available is tempting to rabbits, ants etc and it only takes one evening’s munching for the whole crop to disappear at this stage.

  1. Whilst all this is going on and you are sat waiting for little shoots to emerge above soil level, its good to get your outside spot all ready to go. I’m assuming for the sake of this article that you have a nice secure spot in your garden earmarked for your plants. If you’re planning a guerilla grow then there are some tips on choosing your secret cannabis spot in our guide to guerilla growing autoflowers.

There are two attitudes to planting marijuana on your own land. One is to keep things quiet (plant amongst other plants  for cover, LST and prune cannabis to keep it short etc) .. The other is to say: heck! I’m growing my own medicine, I got a licence: here’s my plant and I’m proud.  (to which I say: well done chap / chappess, I hope you’ve got the dog to keep ’em safe)

It goes without saying that your spot needs to get sunshine for at least 5 hours a day. If summer temps hit above 35C on a regular basis, your plants will need some shade too.

Soil Preparation

Either way you still have to prep the soil before you plant. I know I know its boring to read about, and hard work to do, but I can’t emphasize enough how important soil preparation is. Vegetable growers the world over know the importance of double digging and the same applies to marijuana growers. Your root ball needs to be a third of the mass of your fully grown plant so you need to break and improve at least this amount of soil. Its best to do this the autumn before you plant, as then winter frosts will help break the earth more fully, but no worries if you’ve left it til the spring, just make up for your last year’s laziness with extra muscle behind your spade.

I’ve read examples of 2 foot by 2 foot, but I think if you can, double this figure. View the extracted soil as a cake mix and add plenty of well rotted manure (this improves the soil texture as well as gives some base nutrients). I always add some specialist cannabis compost as well as this is at the right acidity for marijuana. In its natural environment, assuming the roots can seek out some source of water, weed is .. Well it’s a weed and will survive with meager soils and infrequent water. But you don’t want the hit and miss poor yields this can result in, so its worth spending the time and effort now. In order to reach its full potential cannabis is a hungry plant and will devour nutrients during its lifetime. By providing them within the soil you will reduce the need to add nutes later on (although imho you still should)

Many growers advise adding slow release water capsules (polymer) but my experiences with this have been hit and miss. Even in hot temperatures, I personally believe its better to let the plant experience its wet/dry cycle properly and in a garden outdoor grow, you can be in charge of watering. Know your likely summer rainfall and take this into account when deciding whether to use these. What I would say is to add a mulch to the surface of the soil after planting as this will help water loss through evaporation at surface level. A 2″ layer of gravel will do the trick.

Planting your cannabis seedlings outdoors

All my little seedlings are ready to go in their 3″pots and I’m just waiting for the last winter frost to have gone to be sure that the soil temperature is warm enough for their tender little roots. Now you can borrow a tip from the vegetable garden here and warm the soil up by placing a cloche over the cannabis site. Simply weight down some heavy plastic  and let the weak winter/early spring sun warm through to the soil. It only takes a week or so to raise the soil temps a few extra degrees.

(Actually, if you use black plastic and lay over winter, it will help reduce weeds as well)

Weed out anything that is likely to compete with your seedling for the nutrients, water and light available. Whilst you probably want cover plants nearby to disguise your outdoor marijuana, you don’t want other virulent weeds squishing its first weeks outside.

Whilst I’m waiting for the soil temps to rise, and making sure that the spring really has set in, I also acclimatise my seedlings to life in the great outdoors. “Hardening off” is simply a process of exposing the young plants to more and more of their outdoor life whilst not shocking them too much. So at first I remove the propagator lid for a few hours at a time, then after several days they are hardened enough to risk a few hours of morning sunshine on my balcony .. And so on until I’m pretty confident they are ready to take whatever mother nature can throw at them.

Planting is easy. The soil has been nicely prepped and so I simply make a hole twice the size of the pot. Add a handful of cannabis compost to the bottom of the hole, then spread your fingers around the seedling’s stem, tip the pot slowly upside down (letting your fingers support the seedling at its base), tap the bottom of the pot and all should slowly ease out. Plant, fill any gaps around with more compost, firm in gently with the palm of your hand and then water in. Use a good 2 cup fulls of water this first time, it will make sure there are no air pockets trapped in the soil.

Gardens in many parts of the world will benefit from a small temporary greenhouse placed over the plant during spring and into summer. Even a cut off water bottle placed over a young plant, or plastic wrapped frame will help amplify the sun’s rays in springtime. On the other hand summer can bring high heat and too much sunshine, and you may need to think of putting up temporary shading

You have to keep an eye on your young plants for pest infestations and predators. Take time when watering/feeding to inspect leaves for any signs of damage. We’ll cover this later on in the year in more detail.

Is it too late to get an outdoor grow going?

No its not. Remember you can sow an autoflower crop outdoors right up until the beginning of September! But you can also start a standard photoperiod cannabis seed off in April/May: just remember that the longer you leave sowing your seeds, the shorter growth period the plant will have. Once the summer solstice has passed and the days begin to shorten, the plant will start to flower.

Finally good luck with your outdoor grow. Take the opportunity to grow cannabis outdoors organically if you can (although I have to say that the first sign of pests and I’ll throw any old nasty chemical I can at them). There’s certainly something special about well grown outside weed, it’s a gentler and more subtle smoke (more natural if you like) that has a special part in my smoking routine

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