I grow inside so I never thought about it for weed but I’m a huge fan of companion growing for my outside veggies! A simple google search turned up this:
LIST OF COMPANION PLANTS FOR QUALITY MARIJUANA
Companion planting is an inexpensive, planet-friendly long term organic solution to providing natural insecticides and fungicides for your marijuana garden. Living mulch, shade, green manure and added boosts of nutrients, vitamins and minerals can all be achieved by planting growing things, that support other growing things.
The cannabis plant responds to companion planting with more vigorous growth, greater resistance to disease and pests and heavier yields with more essential oil production. A collection of plants grown together that support each other and cannabis are called guilds.
Guilds act as diverse micro-ecosystems, that improve overall soil quality, water penetration and retention and bio-availability of nutrients. Healthy guilds attract beneficial insects and small creatures, that prey on pests, that can damage cannabis. Companions often disguise the unique marijuana silhouette and the potpourri from a number of flowering species obfuscates the pungent aroma unavoidable during marijuana maturation.
Small rock cairns placed randomly among the companion guild will quickly become homes for lizards or large predatory spiders, that will also help keep insects under control. Lizards are very effective hunters of larger insect pests like moths and can vacuum ants at an amazing rate.
Herbs
COMPANION PLANTS FOR CANNABIS, THAT REPEL INSECTS
Basil: This herb is so well regarded, it is called the king of herbs. The sweet aroma of basil in the air acts as a deterrent to aphids, asparagus beetles, mosquitoes, tomato hornworms and whitefly.
Lemon balm: Commmonly known as melissa, lemon balm repels mosquitoes and gnats while attracting beneficial pollinators. Pluck regularly, as it can be invasive and spreads quickly.
Dill: Dill attracts allies like honeybees and hoverflies, ichneumonids and other beneficial wasps. Swallowtail butterfly caterpillars will forgo your cannabis, as they prefer feasting on dill. Spider mites, the curse of the cannabis farmer, despise dill and will stay away in droves. Dill is also an effective repellant for aphids, cabbage looper and squash bugs.
Yarrow: Long rooted yarrow is commonly used as a garden edge plant, so it doesn’t compete for root room with your cannabis. It repels a wide range of bugs and attracts many beneficial predatory insects like ladybugs, aphid lions and hoverflies and several species of desirable parasitic wasps.
Chamomile: The carpet of small bright white flowers will always be buzzing with delighted honeybees and hoverflies while repelling mosquitoes and flies.
Coriander: As a front-line deterrent, coriander repels aphids, potato beetles and the dreaded spider mite and helps attract tachninid flies, hoverflies and a variety of parasitoid wasps that prey on bad bugs or their larvae.
Lavender: The breathtaking flower spears of lavender attract several useful nectar and larvae feeding insects and your plants will always be haloed with stoked bees. Fleas, ticks and mice are repulsed by lavender.
Peppermint: Invasive, but versatile, peppermint will attract the good guys like bees and repels ants, fleas and aphids, flea beetles and mice.
Chervil: Grown in a guild with dill and coriander, a fortress wall of beneficial plants will surround your marijuana and keep it safe from aphids and whitefly, while attracting honeybees and parasitoid mini wasps, that feed on the larvae of hostile insect species.
Alfalfa: This metre high grass repels the dreaded lygus bug, while attracting friends to your patch, such as ladybugs, assassin beetles and several predatory wasps.
Marigold: A companion planting staple, the powerful and pretty marigold repels beetles and leaf hoppers, Mexican beetle and objectionable nematodes. Its buoyant bloom attracts beneficial nectar-eating species.
Sunflowers: The advantage of sunflowers lies in their woody and fibrous resilience. They will draw sap and cellulose hungry pests away from your babies with their bright allure.
lavender
COMPANION PLANTS FOR CANNABIS THAT IMPROVE SOIL QUALITY
Alfalfa: Called the “king of foods”, alfalfa fixes nitrogen and accumulates iron, magnesium, potassium and phosphorous. The deep roots help break up the soil, increasing water penetration and retention and slowing evaporation. It grows quickly; trim and use as mulch around your plants.
Cerastium: Acting as a living mulch, the rapidly growing cerastium shades the soil and increases water penetration and retention. Trim often and use as mulch or compost.
White & Red Clover: The low-growing clovers are very resilient and act as living mulch, encouraging soil friability. All the clovers fix nitrogen, which is released into the local neighbouring plants as it decomposes.
Chamomile: Very efficient at accumulating calcium, potassium and sulphur, chamomile will release these nutrients back into the soil after it died.
chamomile
COMPANION PLANTS & ELIXIRS, THAT BOOST CANNABIS GROWTH
Yarrow: Gardening folklore promises, that yarrow increases essential oil production in neighbouring plants.
Chamomile: As if by magic, chamomile increases the turgor of its neighbours, including cannabis and bolsters essential oil production.
Coriander: A tea brewed from the crushed seeds of coriander can be used as a topical spray to control spider mites far more effectively than commercial poisons.
Alfalfa: The dried stalks can be brewed into a vitamin and mineral-rich tea, that can be sprayed on your marijuana and the whole garden to stimulate growth.
Marigold: One of the oldest companion plants, marigold stimulates growth in their neighbours and releases a chemical into the soil, that repels insects. This effect can last for years after.
Coriander
BIODIVERSITY MEANS HAPPY CANNABIS
All these companion plants also act as camouflage in a number of ways. The variety of texture, colours and depths of perspective help disguise the growing cannabis plant. Smaller growing species like indicas and autoflowers will virtually disappear in a well populated garden. The many fragrant choices of companion plant also help confuse the distinctive cannabis bouquet in a potpourri of exotic smells.
As a diverse mini-jungle awash with colour, aroma and functionality or a select few multipurpose species, companion plants will benefit your marijuana in several ways. Companion plants support growth and vigour, increase oil production and resilience, while repelling bad bugs and attracting the good. Cost effective and pollution-free companion planting is a bonus to the wallet and the planet.