Overview
Cannabis sativa L. ssp. sativa var. sativa, commonly known as marijuana or cannabis, is a herbaceous plant that is widely grown for its medicinal and psychoactive properties. It belongs to the Cannabaceae family and is native to central Asia and the Indian subcontinent. The plant is widely cultivated and consumed globally, with various forms and subspecies exhibiting different physical and biochemical properties.
Appearance
The plant varies substantially in appearance, with the leaves, stems, and flowers differing from subspecies to subspecies. The height of the plant usually ranges from 1.5 to 5 meters and has a distinctive pungent aroma. The leaves are palmate and are composed of serrated leaflets that range from jagged to fissured. The leaves are dark, glossy green, and contain glandular trichomes on their surface that produce the distinctive resinous substance or "hash."
Uses
The plant has long been valued for its medicinal and psychoactive properties. The pharmacologically active compounds produced by the plant, known as cannabinoids, have been found to have various physiological effects on the human body. These cannabinoids include THC (tetrahydrocannabinol), which is responsible for the psychoactive effects, and CBD (cannabidiol), which has anti-inflammatory and analgesic properties and is used in the treatment of various medical conditions. The plant is also used recreationally for its psychoactive effects. Cannabis has been traditionally used for thousands of years as medicine, and for recreation and spiritual purposes, and it continues to be widely used today in various forms and preparations.
Common names
Cannabis sativa L. ssp. sativa var. sativa has many common names including marijuana, weed, pot, bud, ganja, herb, Mary Jane, grass, and many others. Some names are region-specific, while others are commonly used throughout the world. The names are often used interchangeably to refer to the plant's various preparations and subspecies.
Light Requirements
Cannabis sativa L. ssp. sativa var. sativa requires a significant amount of light for optimal growth and yield. During the vegetative growth stage, the plant requires a minimum of 18 hours of light per day. However, once the plant enters the flowering stage, it requires a light cycle of 12 hours on and 12 hours off. The plant responds best to full-spectrum light with a Color Rendering Index (CRI) of 80 or higher.
Temperature Requirements
The ideal temperature range for Cannabis sativa L. ssp. sativa var. sativa is between 20°C and 30°C during the day and 15°C to 20°C at night. The plant is sensitive to both high and low temperatures and may experience stunted growth or even death if exposed to extreme temperatures. Temperatures above 35°C during the day and below 10°C at night can cause significant damage to the plant. Additionally, temperature fluctuations must be minimal, as they can cause stress and damage to the plant.
Soil Requirements
Accommodating soil conditions are critical for the growth and overall productivity of Cannabis sativa L. ssp. sativa var. sativa. The soil must have a neutral pH, between 6.0 and 7.5. It must also contain ample amounts of organic matter, nutrients, and oxygen to support proper growth. Furthermore, the soil must provide adequate drainage to prevent waterlogging, which can cause root rot. If the soil is deficient in any essential nutrient, such as nitrogen, phosphorus, or potassium, the plant may not grow evenly, and it may suffer from nutritional deficiencies.
Cultivation Methods
Cultivating Cannabis sativa L. ssp. sativa var. sativa requires a few critical steps. It is essential to select the right location, where the plant will receive plenty of warmth from the sun.
The soil should be well-draining with some organic matter mixed in. Planting seeds or seedlings should be done after the last expected frost or indoors for a few weeks before spring planting.
The ideal temperature range is between 60 and 80 degrees Fahrenheit.
Watering Needs
Cannabis plants like a moist environment. Therefore, it is crucial to ensure the soil is moist but not waterlogged. Overwatering can lead to root rot and ultimately kill the plants. The frequency of watering depends on the climate and soil condition.
Water the plants slowly to allow the water to seep into the soil. It is essential to water the plants early in the day to allow some time for the water to evaporate and leaves to dry before nightfall. Wet plants can attract pests or get moldy.
Fertilization
Proper fertilization is crucial for the healthy growth of the Cannabis plant. Applying the right amount of fertilizer is a bit tricky as too much can harm the plant, and too little will not allow it to reach its potential.
The best way to fertilize Cannabis sativa L. ssp. sativa var. sativa is by using organic materials such as compost, worm castings, bone meal, and blood meal. It is advisable to feed the plant gradually over several weeks to avoid over-fertilization.
Pruning
Pruning is essential to increase yield and promote a healthier plant. Removing the larger and older leaves can help to increase the amount of light reaching the flowering sites. It will also promote the growth of smaller leaves that are crucial for photosynthesis.
Trimming can be done three to four weeks before the plant's natural flowering period to help it focus energy and resources on producing larger buds, increasing their potency and size. Be careful not to over-trim the plant - it still needs enough foliage to support its structure.
Propagation of Cannabis sativa L. ssp. sativa var. sativa
Cannabis sativa L. ssp. sativa var. sativa is propagated via both sexual and asexual reproduction methods.
Sexual propagation
Sexual propagation involves the use of seeds. Cannabis sativa L. ssp. sativa var. sativa plants grow male and female flowers on separate plants. The male plant produces pollen that fertilizes the female plant's flowers. The fertilized female plant produces seeds that can be harvested and later planted to grow new cannabis plants.
Asexual propagation
Asexual propagation involves the use of vegetative plant parts, such as cuttings or clones. This method produces identical genetic copies of the parent plant, eliminating genetic variation. Cannabis sativa L. ssp. sativa var. sativa plants are commonly propagated asexually due to the inheritable characteristics that are desirable in the plant, such as terpene profiles and THC/CBD content.
To propagate via cuttings, a small piece of the parent plant (stem, branch, or leaf) is cut and placed in water or soil. The cutting will grow roots and develop into a new plant. Cloning involves taking a cutting from the parent plant and placing it in rooting hormone and a rooting medium. Once roots have developed, the clone can be transferred to soil or hydroponic media to mature into a new plant.
Disease Management for Cannabis sativa L. ssp. sativa var. sativa
Cannabis sativa L. ssp. sativa var. sativa is susceptible to several diseases that can cause significant damage to the crop. Here are some common diseases that affect the plant and ways to manage them:
- Bacterial Blight: This disease is caused by the bacterium Pseudomonas syringae pv. Cannabis. It affects the leaves, stems, and flowers of the plant and causes water-soaked lesions that turn brown and necrotic over time. The best way to manage this disease is by preventing it from entering the field. Ensure to maintain proper sanitation practices and avoid overhead irrigation.
- Gray Mold: This disease is caused by Botrytis cinerea fungus and affects all above-ground parts of the plant, including flowers and leaves. Gray mold appears as a gray-brown fuzz on affected plant parts. The best way to manage this disease is to provide adequate ventilation and reduce humidity levels in the growing area. It could also be managed by applying fungicides early in the growing season.
- Root Rot: This disease is caused by several fungal species such as Pythium spp., Rhizoctonia spp., and Fusarium spp. It causes the roots to rot and die, making it challenging for the plant to absorb the nutrients it needs to grow. The best way to manage this disease is to avoid over-watering, maintain proper drainage, and plant in well-draining soils.
Pest Management for Cannabis sativa L. ssp. sativa var. sativa
Aside from diseases, pests present a significant threat to the growth and yield of Cannabis sativa L. ssp. sativa var. sativa. Here are some common pests that affect the plant and ways to manage them:
- Spider Mites: Spider mites are tiny arachnids that feed on the plant's sap, causing yellowing and stunting of leaves. The best way to manage spider mites is to introduce predatory mites and keep the growing area clean and free of debris.
- Aphids: Aphids are small insects that suck the sap from the plants, reducing vigor and yield. The best way to manage aphids is to introduce beneficial insects like ladybugs, lacewings, and parasitic wasps. Alternatively, one could spray insecticides that contain soap or oil, often referred to as neem oil.
- Thrips: Thrips are tiny insects that feed on the plant's tissues, causing leaves to turn bronze and distort. The best way to manage thrips is to use yellow sticky traps and remove any debris that might serve as a hiding place for them. Also, beneficial insects like mites and parasitic wasps can help keep the thrips in check.
By taking the necessary precautions and implementing management practices, growers can significantly reduce the incidence of diseases and pest attacks in Cannabis sativa L. ssp. sativa var. sativa and improve yield and plant health.
