A Beginner’s Guide to Growing Cannabis

Imagine a plant that can be trained to give us food, fuel, clothing, rope, building materials and medicine all while cleansing the soil and attracting beneficial pollinators and wildlife in just one season. Well that plant’s name happens to be Cannabis Sativa! The benefits of this plant are many and you could spend a whole lifetime exploring each one, but above all else this plant is a fantastic candidate for any garden this season. It grows rapidly when planted properly, it adds a beautiful dimension to the landscape, and at the end of the season you can make use of the harvest in so many different ways. Spring has already sprung here in Virginia but right now, in early May, is actually the perfect time to plant Cannabis seeds. In this post I will detail the basic process for planting and growing Cannabis and some common things to look out for when buying seeds and harvesting when the time comes.

Caption A beautiful purple female Cannabis plant in Kandahar, Afghanistan

So first, let’s get to know who this plant is a bit to understand what we want to grow this season. The Cannabis Sativa plant has been traced back to originating somewhere in central Asia, most likely somewhere between the Caucasus Mountains and Central China. It is a dioecious annual plant which simply means there are male and female plants required for pollination, and it does all of its growing and reproducing in one season.  It is actually one of the first plants that humans domesticated from the wild more than 10,000 years ago. Since then, it has found a home in nearly every bioregion on Earth from the equator to the arctic circle and everywhere in between.

Caption A map of Cannabis’ migration across the world.

Caption An example of male versus female.

Our ancestors clearly recognized the possibilities that a fast growing and adaptable annual plant like this had for human needs, so they began to select for which characteristics were needed at the time. Extremely large plants with big strong branches were used for building materials and for the strong fibers that come from the outer bark to make rope. The female plants that had large flowers were pollinated and used for producing the nutrient rich seeds that we still eat today in the form of hemp seeds. While female plants that had flowers that produced lots of resin were used for their medicinal activity. It can perform so many functions, and humans have largely preserved all of those possibilities to this day. So a good question to ask yourself is, what kind of Cannabis plant do I want to grow? 

There are no wrong answers! But if you want a certain result, you have to know how to get there. So let’s talk a bit about seeds and how to pick the right ones for you.

When going to buy seeds, there are a few key terms to understand to know whether you will get males or females. If you want to get both sexes to show up in your garden, the seeds are known as ‘Regular Photoperiod’ seeds. These are the truest expressions of Cannabis plants because they were created using direct pollination and will give the best combination of the two parent plants. For someone who just wants to grow some plants to add a dimension to their garden, these are the perfect seeds to start with because you will likely get many different looking plants that are fun to compare and contrast. These seeds also work best if you want to create seeds as well, because you will get a mixture of male and female plants which increases the chance for pollination.

If you are looking to harvest flowers for medicinal activity, it is advised to cull male plants from the garden before pollination occurs. But why is this? It turns out, when no males are present and the female flowers remain unpollinated, the female plants invest more of their energy into resin production, which increases medicinal activity. The term ‘sinsemilla’ in Spanish means “without seeds” and is often used to refer to medicinal cannabis flowers. In this modern age, Cannabis breeders now have a technique of producing “Feminized Photoperiod” seeds which usually result in between 90-100% female plants. Most people who are interested in flowers favor feminized seeds, but they usually cost a lot more so weighing the options is important!

Caption Cannabis seeds at different stages of ripeness.

Finally, breeders and seed banks will often offer many varieties that have different characteristics. Be mindful of which cannabinoids you are selecting for (CBD, THC, etc. ) and what the plants have been bred to do. Seed banks and breeders that give lots and lots of information are strongly preferred over seeds that only have a simple name. You can absolutely find plants that are bred for fiber use or for seed production, you just might have to look outside of a seed bank that primarily specializes in selling varieties that are for their flower qualities. I also like to buy seeds that have been bred locally because they tend to be much happier in our climate than ones that grew in, say, Colorado. But there are lots of fantastic places to find seeds, so just verify that it is a trusted source.

Now for the best part… You’ve got your seeds in hand and it is time to plant. With all the hubbub online about growing cannabis making most people’s heads spin, I am here to tell you that it grows just like any plant in your garden! You will learn very quickly from growing this plant even once, it likes to be self-sufficient and is very resilient. Mastering it takes time like anything. The real problems arise when you try to grow it indoors and simulate the conditions of Mother Earth, but that is a topic for another day.

To plant your seeds, I recommend a high quality, well draining potting soil or area of your garden that has a rich amount of compost and organic matter in it. I usually start plants in 3-inch pots just so I can monitor them more closely, but direct sowing is absolutely fine as well. Plant the seeds about half an inch to an inch into the soil, and bonus points if you can find the tip of the taproot and position it facing upwards. Cover and keep lightly moist until germination in 3-9 days. A general rule for Cannabis is that it doesn’t like to be over watered at any stage, they drink lots of water but never want to be sitting in it. After germination, wait until at least 7 sets of leaves have appeared before pruning. If you are transplanting, make sure to enrich the area you plant on with extra compost or manure, Cannabis is a heavy feeder and doesn’t shy away from extra fertile soil. If you direct sow, put compost around or underneath before you plant.

Caption The taproot inside the seed.

Caption A brand new Cannabis seedling.

Once your sprouts are off and running, they will begin rapidly expanding with vegetative growth. They can put on multiple inches a day in ideal conditions. They will continue this growth until we pass through the summer solstice, which marks the longest day of the year and the point where each day begins to get less daylight hours until the winter solstice. Remember that ‘photoperiod’ bit from before? This means that the plants sense this reduction in light and begin to realize that winter is approaching. The plants then know that it is time to either produce their flowers or pollen. After making one last burst of growth in mid July/August, the plants will finish their pollination cycle sometime in October or November depending on the variety. There is plenty of info elsewhere about harvesting techniques depending on what you want to harvest, but in Virginia the main thing to be aware of is the high levels of cold moisture we get in the late season. This leads to quite a bit of moldy conditions for many people’s crops so sometimes an earlier harvest before a big rainstorm in October is your best bet.

There are truly so many possibilities for this plant in your garden and once you have one successful season, you will see how much fascination it can provide for someone who loves to admire gorgeous plants. Growing different varieties in Virginia is also a great way to continue your relationship with cannabis because so many varieties thrive in this temperate climate. It also makes a fantastic companion plant for all sorts of vegetables, herbs and spices, and ornamental flowers that you may be planting. So if you really want to invite a stunning addition to your garden, consider one of our oldest friends from the plant kingdom!

By Zachary Wajsgras