As with all plants, the quality of any cannabis crop is hugely influenced by factors such as soil composition, predation by pests and disease outbreaks. While many gardeners attempt to tackle these issues using chemical fertilisers and pesticides, this often produces an unbalanced ecosystem that can result in long-term soil degradation and weaker plants. Companion planting, on the other hand, is an eco-friendly and sustainable method of enhancing the quality of your cannabis, and when done well can produce far better results than any chemicals.
What is companion planting?
Modern agriculture typically relies on monocultures, whereby an entire field is dedicated to a single type of plant and all other species are eliminated. However, you’ve probably noticed that such monocultures never occur naturally, and that forests, fields and meadows always contains a huge variety of plants growing side by side. That’s because biodiversity is necessary for the health of every plant in a given ecosystem, and each species benefits from having heterogeneous neighbours in a number of ways.
For instance, plants that require lots of nitrogen, potassium or calcium tend to grow best next to other plants that fix these nutrients into the soil. Others, meanwhile, thrive when in close proximity to plants that repel certain pests.
Biodiversity also provides protection from many kinds of disease. If you think about it, a monoculture is a bit like a crowded Tube carriage, where if one passenger carries an infectious disease then everyone else on the carriage is likely to catch it. Introducing other plants can prevent this by creating buffers between individuals of the same species, thereby ensuring the infection can’t spread.
Companion planting therefore involves harnessing the benefits of biodiversity by growing certain helpful species next to your cannabis plants. There are many plants to choose from, each of which brings its own benefits, so you might want to experiment by growing some of the following companion plants close to your marijuana.
Plants that provide soil nutrients
Several types of clover – such as red clover and white clover – can be used to fix nitrogen into the soil. This is because their roots harbour certain bacteria that capture nitrogen from the atmosphere and release it into the soil as these roots decompose. Clover is used as a companion plant for many types of crop as it also provides an excellent ground cover that stops water from evaporating from the soil.
Beans are also great nitrogen fixers, while alfalfa does a similar job to clover but can sometimes grow a little too vigorously, which means it may need thinning out every now and then to prevent it from blocking out other plants.
Chamomile and borage, meanwhile, release lots of calcium and potassium into the soil, especially as they decompose. Cannabis requires both of these minerals in order to grow and produce cannabinoids, so it loves to have these plants as neighbours.
Similarly, comfrey uses its deep roots to bring up nutrients from deep in the soil, making it another great companion plant for cannabis. It can quickly become very bushy, however, so it may be necessary to cut it back regularly. The cut leaves make a fantastic mulch, which can be left to rot around the roots of your marijuana plants, supplying them with loads of vital minerals.
Plants that provide protection from pests
Bugs like cabbage flies find the aroma of marigold absolutely repulsive, so planting it near your cannabis is a sure-fire way to repel these pests. On the other hand, marigold’s yellow flowers attract aphids. This may sound like a bad thing as you generally want to keep these leaf-eating critters away from your garden, although it can actually be beneficial as it means that many of the aphids that would otherwise munch on your cannabis plants will instead be drawn to the nearby marigold.
Opinions are generally split on whether marigold is a help or a hindrance, so it might be worth experimenting with this in order to find out.
Dill, on the other hand, is widely accepted as one of the best pest-repellents that nature has to offer. Aphids, mites and all kinds of other bugs will stay well away from your garden if you plant this easy-to-grow (and delicious) companion plant.
Plants that enhance the quality of cannabis
One plant that really needs a mention is nettle. Yes, regular stinging nettle. Aside from the fact that it’s one of the most nutritious plants you could ever eat, it is also an absolute diamond of a companion plant, for many reasons.
For one thing, it provides great camouflage for marijuana, which is important if you’re trying to go under the radar. Aside from that, it produces huge amounts of nectar, which attracts ladybirds and many other predatory insects that love to prey on aphids and mites.
Yet what makes nettle really stand out from other companion plants is the fact that its pollen actually stimulates the production of terpenes in cannabis trichomes, resulting in more flavoursome bud.
Similarly, both basil and yarrow are often said to boost terpene synthesis and enhance the flavour of cannabis, though the latter should always be grown around the edges of a garden so that its roots don’t outcompete those of other plants.