Even if you are a natural green thumb, if you’ve never grown cannabis before, there is an enormous amount of information you need to learn before setting up your grow space. In order for your plants to thrive, you need to get the environment just right — in the “Goldilocks Zone,” if you will. While there is much more that goes into finding that perfect balance, in this article, we will focus on the basics of ensuring your cannabis plants get the right amount of light, water, and nutrients.
Light quality is arguably the single most important factor in your grow environment. Here is some high-level information about some of the most popular types of grow lights used for growing cannabis indoors.
HID Grow Lights
HID (high-intensity discharge) lights are perhaps the most popular choice in the industry because they are efficient and effective. While more expensive than incandescent or fluorescent lights, they produce more light, providing more value. In contrast, LED lights are more efficient, but more expensive than HID grow lights. For many growers, this makes HID grow lights a happy medium, but it depends on your priorities. Also, keep in mind that HID grow lights run very hot, so you’ll need air-cooled reflector hoods for mounting your lamps, as well as ducting and exhaust fans.
The two main categories of HID lights are:
- Metal halide (MH), which are usually used during vegetative growth
- High-pressure sodium (HPS), which are usually used during the flowering stage
Fluorescent Grow Lights
Fluorescent grow lights present their own advantages, particularly to hobbyists with small grow spaces. They tend to be less expensive since the reflector, ballast, and bulbs are all included in one package. They also do not generate as much heat as HID lights, so they don’t require a cooling system.
However, fluorescent lights are less efficient. Because of this, more fluorescent lights are required to generate the same output as other options. For example, you would need 19, 4-foot-long fluorescent bulbs to be equivalent to one 600-watt HPS bulb.
LED Grow Lights
Light-emitting diode (LED) technology has recently been adapted to create indoor growing lights that are highly efficient. The primary downside to LED grow lights is cost: you can pay up to 10 times more for LED lights than HID fixtures. However, depending on your priorities, LED offers many advantages that attract growers — they are long-lasting, more energy efficient, and create less heat.
That being said, quality is king — there are many lower quality LED lights that are marketed to growers, so be sure to do research before investing.
Induction Grow Lights
Induction lamps, also known as electrodeless fluorescent lamps, have also recently been adapted for the indoor grower. They are comparable to fluorescent lights, except that they last longer and are more efficient. The biggest drawback is that they aren’t widely available and can be quite expensive.
Watering your cannabis plant isn’t as simple as pouring some tap water into the soil every now and again. Overwatering and underwatering are both common causes of plant death, yet there isn’t an exact recipe for how often you water your cannabis. Remember, your plant is constantly growing, and this means their needs will change too. It’s important to keep a close eye on cannabis plants to meet their watering requirements. In general, how much and how often you water will depend on your plants’ size, stage of growth, and overall health.
Take the time to observe your plants when you’re thinking of watering them. What color are the leaves — are they green, or are they starting to yellow? Do they look strong or are they starting to wilt? Is the soil wet or dry?
Beginner growers often make the mistake of overwatering their plants, so remember that the roots need to cycle wet and dry in order to grow out. On an overwatered plant, leaves will be dark green and begin to curl. On an underwatered plant, the leaves will also droop but will appear yellow or brown.
A good rule of thumb is to check the soil by sticking a finger a couple of inches into it. If this seems dry, then it’s time to water. Keep a log of when you water your plants to ensure you follow a proper water cycle. Also keep in mind that as they grow taller, you will need to water them more frequently, so you will have to change your schedule over time.
Choosing nutrients and learning how to use them is one of the most intimidating aspects of growing cannabis for many first-time home growers. There are so many options out there that it can feel difficult to make the right choice. This brief overview may help you feel more informed about these important decisions.
Important Mineral Elements
Below is a list of mineral elements essential to cannabis plant growth. Plants also need carbon, hydrogen, and oxygen, all of which they derive from air or water.
- Nitrogen. Nitrogen is especially important during the vegetative stage. Plants need nitrogen to produce chlorophyll, meaning that without it, the plant cannot convert the light into energy and grow. Nitrogen is also part of the amino acids that act as building blocks for the proteins in the plant. Without these, your cannabis plants will be weak. Nitrogen also plays a role in ATP, the process through which the plant cells control energy use. Finally, nitrogen is essential to creating nucleic acid, which is necessary for DNA or RNA. Without it, your plant cannot grow or multiply.
- Phosphorus. Your plant needs phosphorus to produce healthy buds. Phosphorus helps to make other nutrients available to the plant. Without sufficient phosphorus, plants may not even flower. You can tell a plant is deficient in phosphorus when there is a purple hue in the veins of the leaves.
- Potassium. Potassium plays an essential role in many jobs related to regulating plant systems. Osmoregulation, the regulation of water and salt concentrations in the plant, requires potassium to control the opening and closing of the stomata, which is the passage through which the plant exchanges H20, oxygen, and CO2. Potassium also starts the production of ATP, which stores energy produced during photosynthesis by creating glucose. Without enough potassium, plants are weak and often appear burnt because they cannot regulate the exchange of CO2, H20, and oxygen.
- Calcium. Plants need calcium for the structure of the cell walls. New growth cannot develop without calcium. This means plants deficient in this mineral are stunted. The leaves will also begin to curl, and rusty spots are common on the plant.
- Magnesium. Magnesium is the central molecule in chlorophyll. Without it, plants cannot generate glucose through photosynthesis. This means without magnesium, plants can’t convert energy from sunlight. In addition to helping in the creation of glucose, magnesium also helps the plant metabolize glucose. Plants with magnesium deficiencies will have yellowing leaves.
How to Use Nutrients
Fertilizer, nutrient solutions, and other additives are all used to control the amount of nutrients a plant gets. These products are categorized based on how much of each of the three main elements (nitrogen, phosphorus, and potassium) they have. These are indicated by three numbers you can find on the label. For example, a product labeled “10-4-4” has 10% nitrogen, 4% phosphorus, and 4% potassium. These are labeled in this order every time.
The best option for ensuring your plants get the right nutrients is to use organic soil. This tends to be far more forgiving than hydroponic systems, for example. With the proper soil blend, you don’t need to use many (if any) additives to give your plants the proper nutrients. You can find premixed organic soil solutions, though these tend to be more expensive, or use organic ingredients such as bone meal, wood ash, and Epsom salts to provide the essential nutrients.
The key to organic growing is ensuring there are healthy and varied soil microbes and mycorrhizae in the soil. You can buy premixed organic soils designed for these conditions, invest in certain organic additives, or better yet, actively aerated compost tea (AACT), which relies on the soil life to do most of the work in terms of turning organic matter into nutrition for the plant.
As a cannabis cultivation service in Massachusetts, we have extensive knowledge of growing cannabis, and we’re dedicated to spreading the wealth. To learn more about homegrown cannabis, follow our blog, or feel free to reach out about our service.