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A lot of indoor cannabis growers struggle with yields. It’s fantastic to grow your own weed, but you must grow enough of it! Otherwise, growing may feel like a waste of time and effort.

Luckily, cannabis yields don’t have to be a mystery. There are specific factors that cause yields to be big or small, and nearly all of them are under your control. The following article contains a comprehensive list of what you can do (both before and after buds start forming) to increase yields.

There are a few ways to think about increasing cannabis yields indoors. Some growers want to maximize the yields for their grow space, and don’t care what it takes to increase yields overall. Other growers are looking at returns from more of an economic perspective, wanting to get the best yields for the electricity/cost, but maybe aren’t as concerned with how much space it takes. Lastly, there are many growers just looking to grow huge impressive buds and don’t care about maximizing anything else. This article is going to talk about all three. No matter what you’re looking for, we’ve got you covered.

Without further delay, it’s time to learn how to increase your yields!

Before Buds Start Forming

These are the actions you can take to prepare for a fruitful flowering stage.

1.) Choose High-Yielding Genetics

A lot of growers focus purely on their setup, nutrients, growing technique, and other aspects of their environment, yet don’t pay much attention to strain.

Your genetics actually have a tremendous effect on yields. If you grow two plants in the exact same conditions, chances are one will produce more bud than the other. Sometimes the yield differences between strains are enormous.

2.) Grow Correct Number of Plants

The number of plants can affect your total yield in two ways:

• More Plants – Growing a lot of small plants lets you fill a grow space faster, resulting in more harvests in a year if everything else is the same. If you increase the number of harvests, you’ll produce more buds in the same amount of time. This idea is the basis of the Sea of Green method.
• Fewer Plants – You can achieve the same yields with fewer plants by letting them get big enough to fill a space, but it takes longer in the vegetative stage for plants to get to the final size. Depending on how much extra time, this can push back harvest time and reduce the total number of harvests you can produce in your grow space. If you must limit the number of plants (many growers have legal plant limits), you can maximize yields with training techniques such as manifolding.

3.) Use The Right Pots

Choose the right container type and size for your setup.

• Air ports and fabric pots allow air to get to roots from the sides, resulting in significantly faster growth rates. The one downside is these pots need to be watered about twice as often because they dry out more quickly.
• Pots that are too big for your plant tends to slow growth, especially young plants that get overwatered. Learn how to water a small plant in a big pot so it grows as fast as possible.
• Too-small pots restrict plant roots and keep plants from growing as big as they could. Plants in big pots can get huge!
• If possible, it helps to start plants in a smaller container and transplant to bigger ones after they’ve started growing vigorously.

What’s the optimal size for your final plant container?

A general guide is to have around 2 gallons per 12″ of the final desired height. Big plants often need a bit more. The following chart isn’t perfect since plants often grow differently, and some plants are short and wide instead of tall, but this is a good rule of thumb. If your final (desired) plant size is…

• 12″ ~ 2-3 gallon container
• 24″ ~ 3-6 gallon container
• 36″ ~ 5-8 gallon container
• 48″ ~ 7-10 gallon container
• 60″ ~ 8-15+ gallon container

Go bigger if you plan to spend time away from your plants! Bigger root space gives you more of a buffer if plants need to be unattended for days at a time.

To be continued…

Speaking of signs of overwatering, topsoil issues is something that you can’t ignore. We’ll also share with you the common causes of overwatering. Let’s read on:

5.) Topsoil issues

When it comes to diagnosing your sick plant, examining the topsoil can help you narrow down the possible problems. If you notice the following issues with your topsoil alongside any of the plant symptoms above, you can feel pretty confident that overwatering is your villian.

• Fungus gnats
• Green algae
• Soil is constantly wet or waterlogged
• Topsoil has turned solid
• Indents or divots where water is getting poured heavily

Notice how the grow medium here looks completely soaked with green algae growing on top. Green algae only grows when topsoil is staying wet too long. That lets you know the problem is overwatering in this case without even looking at the symptoms on the plant itself.

Just like algae, fungus gnats can only live when the topsoil is staying wet for long periods of time. If you see fungus gnats (tiny black flies buzzing around the soil) it almost always means you’ve been overwatering the plants. If the plant has a bad infestation of fungus gnats, which may means it’s being overwatered. At this point, it’s hard to tell whether the fungus gnats or the overwatering is directly causing the symptoms, but the solution is the same: better watering habits.

It’s common for topsoil to look hard and almost solid if it’s staying too wet for too long. If you’re also seeing green algae and permanent deep divots/holes where the water is getting poured, you can feel pretty certain you’re overwatering.

Solution: How to Water Plants Perfectly

It’s common for these issues to be confused for something else. One of the things that can be difficult about diagnosing problems is that many symptoms can be caused by multiple different factors. For example, nutrient deficiencies can be caused by lack of nutrients, but also incorrect pH, bugs, overwatering, etc. Yet if you’re seeing droopiness alongside mysterious symptoms, especially with waterlogged topsoil, there’s a strong chance that watering habits may be the true culprit.

Before you can fix the issue, you have to identify exactly where you’re tripping up. “Overwatering” is a broad term that describes a situation with lots of water at the roots but not much oxygen. There are a few different ways to get there.

Common Causes of Overwatering

• Watering too often
• Watering too much at a time
• Poor draining grow medium (dense, thick, muddy, etc.)
• No drainage holes to release runoff water out the bottom
• Letting plant sit in runoff water (always remove runoff after watering for the best results)
• Poor transpiration (plant can’t efficiently evaporate water through the leaves). This prevents plants from “sucking up” water from the roots like a straw, and results in slow water uptake

Environment: Overwatering is More Likely When…

• Weak grow lights – Plants just don’t drink as much under weaker lights. That means overwatering is more common with small grow lights.
• Small plant, big pot – When plants are small, young, or unhealthy, they just don’t drink as much. When they’re in a container that’s much bigger than the size of their roots, it’s easy for them to drown because they use up all the oxygen and then roots are sitting in stagnant water. The best way to help these plants is give less water at a time until they’re bigger and drinking more.
• Heat (above 85°F / 30°C) – In the heat, oxygen is less available at the roots. Keeping roots from getting too hot helps the plant better deal with heat. That’s part of why plants become more resistant to heat after they get bigger. The big plants help shade the roots from the grow light, and grow lights are typically further away because plants are taller. This combo prevents roots from heating up as much and plants just become more resistant overall.
• Cold (below 70F) – In the cold, plants are evaporating less water from their leaves, which means they drink less, making it more likely for roots to stay too wet, too long. Roots especially hate being cold. Yeah, roots are kind of picky. Plants can thrive in much cooler ambient temperatures as long as you keep the roots relatively warm. For example, don’t let the roots sit directly on a cold basement floor. Keeping plants slightly up off a cold floor will help them handle a wider range of temperatures without slowing down.
• Humid (above 65%) – Just like with cold, high humidity prevents water from evaporating properly from the leaves. That means plants are drinking less overall, which increases the chance of water hanging out too long at the roots.
• Lack of Air Circulation – A slight breeze is good for your plants. Not only does a little airflow prevent hot spots and strengthen stems, but plants are also better able to evaporate water off their leaves. Gentle air movement also helps keep topsoil from staying wet for too long and can even offer some protection against bugs like fungus gnats and spider mites.

A perfect environment helps plants deal with a variety of root moisture levels without issue. In fact, nearly all environmental problems except low humidity (too dry) increase the chance of plants suffering from overwatering. Extremely dry air can cause slow or unhealthy growth, but it does help plants drink more quickly and water evaporate faster. You can still overwater plants when the air is too dry, but it’s a little less common.

To be continued…

We have discussed the color effects on plant growth. Light spectra will affect plant growth in different ways depending on environmental conditions, plant species, etc. Typically, chlorophyll, the molecule in plants responsible for converting light energy into chemical energy, absorbs most light in the blue and red spectra—both of which are found in the peaks of the 400-700 nm PAR range—for photosynthesis.

Red Light

Phytochromes, which are the principal receptors for light in the red/far-red region of the spectrum (600–750 nm), play an essential role in regulating seed germination, the blooming cycle, root development, and shade avoidance. In green plants, light is a crucial factor in determining the establishment of an emergent seedling. Maximizing photosynthesis using supplementary lighting rich in the red/far-red spectral region during early development and/or under dense canopies can be critical for seedling survival.

Red light spectrum (600-700nm) is considered the most efficient at driving photosynthesis—especially in the flowering stage for biomass growth, which is particularly important to cannabis growers—as it’s highly absorbed by chlorophyll pigments. Red light wavelengths (particularly around deep red 660nm, since that’s where a plant senses bright sunlight exposure and its chlorophyll absorption peaks) encourage stem, leaf, and general vegetative growth—and especially the elongation of leaves and onset of flowers.

Far-red light spectrum (700-850 nm) can also affect plant growth; one way is by initiating a shade-avoidance response. From 730nm and beyond, there is a higher ratio of far-red to red light, and so if a plant detects “shade” from another plant or leaves higher up the canopy, then elongation of its own stems and leaves occurs.

Far-red can also promote flowering, and in certain plants, has been shown to increase fruit yield. In short-day plants like cannabis, which rely on longer periods of darkness, 730nm can be used at the end of a light cycle to promote flowering. Many growers are experimenting with interrupting the dark cycle with bursts of red light to boost growth and flowering.

Blue Light

Blue light spectrum (400-500 nm) is widely responsible for increasing plant quality, especially in leafy crops. It promotes the stomatal opening, which regulates a plant’s retention of water and allows more CO2 to enter the leaves. This can affect leaf movement, leading to flatter and expanded leaves, which results in a more efficient surface for light absorption.

Blue light also drives peak chlorophyll pigment absorption (peaking at 439 nm and 469 nm), required for photosynthesis. The 400-500 nm blue light spectrum is essential for seedlings and young plants during vegetative stages as they establish a healthy root and stem structure—and especially important for reducing stem stretching when necessary.

In addition, blue wavelengths affect phototropism (the orientation of the plant in response to light, either towards or away from the light source).

Broad Spectrum (White) Light

The ideal grow light spectrum for plants depends on several factors. In some crops, blue light can benefit nutritional levels and coloring, while a higher red to far-red ratio can help with leaf size and flowering. While red is generally the most responsive light spectrum for plants, it’s important to note that its efficacy really steps in when in combination with other PAR wavelengths. A balanced pairing with blue light is necessary to counteract any overstretching, like disfigured stem elongation. Certain plants (such as cannabis) use not only the 400-700 nm PAR-spectrum light for photosynthesis, but also the wavelengths outside of this range.

Individual light combinations should therefore be adjustable throughout the life of a plant to optimize desired traits. Broad spectrum white lighting—often referred to as full spectrum lighting—means the complete spectrum of light given by sunlight. This means that the wavelengths of broad spectrum lighting include not just the visible 380-740nm wavelength range (which we perceive as color), but also invisible wavelengths such as infrared (IR) and ultraviolet (UV). Effective broad spectrum light can help accelerate flowering, increase nutrition, and speed up the rate of growth.

By using full spectrum LEDs to select the exact quantities of red and blue light, chlorophyll pigments can absorb more of the light that they need. This means that when used strategically, bigger leaves and better flowering periods can occur without unnecessary stress.

Aokairuisi LED grow lights are available in various styles and sizes for a range of crop growing environments—whether indoor open-bed, indoor top light, vertical farming, or greenhouses. Here are some of the many benefits of Aokairuisi LED grow light solutions:

• Superior PAR output, photon efficacy, and light uniformity;
• Scientifically engineered spectrum for optimal PAR photon efficacy and plant growth;
• Fully assembled, CE and UL listed, and durable industrial grade construction;
• Enhanced crop yield and quality;
• Total energy usage reduced by more than 50%;
• More than 50000 hours lifetime, with no lamp changes;
• Superior light delivery over the life of the fixture;
• Dimmable for all phases of plant growth/production.

Growing Tomatoes Indoors

Growing vegetables all year long can be quite a challenge, especially if you live in an area that doesn’t have “Summer” all the time. For hobbyist tomato farmers and commercial tomato growers, lighting is one of the main components.

Tomatoes need at least 6 to 8 hours of sunlight a day. This sunlight can be natural or artificial. In most locales, artificial lighting will be necessary to meet the 8 hours of daylight for tomatoes to be grown year-round.

Not all artificial light is created equal

Fluorescent – less expensive, at least initially.
These types of grow lights are generally less costly than other types. However, fluorescent light fixtures don’t provide the sun-replicating full spectrum light needed for tomato plants. Not only will this choice of fixture yield fewer tomatoes, but it will also consume more energy and investment when the bulbs need replacing.
 
HID (high-intensity discharge) – better yield than fluorescent but energy-hungry heat machines.
There are two subcategories in the HID grow light (HPS – high-pressure sodium; MH – metal halide), and because they provide only one color in the spectrum, both kinds are required at different stages of a plant’s growth cycle.  Switching requires a redundant set of fixtures or changing the bulbs when the crop enters a new growth stage. These lights are powerful and require specific rigging and fixtures. HID bulbs need replacing more frequently, which adds to the overall cost. 
 
LED Grow Lights – worth the investment.
LED grow lights are more cost-efficient in the long run since they use the least amount of electricity. Because they don’t burn a gas to create heat, they are much cooler than fluorescent or HID. The light wavelengths are fuller and contain both red and blue lights, yielding more tomatoes per plant. These fixtures utilize light emitting diodes and require little to no maintenance over the course of a long service life.

LED Grow Lights – looking deeper

LED Grow lights with higher color temperatures (5000-6500K) provide the full light spectrum and promote all vegetative growth stages. Grow lights with lower color temperatures (2500-3000K) encourage flowering and are often used when the plant develops fruit. Tomatoes need both red and blue light to grow and produce fruit.
Blue Spectrum Light 
Blue light is vital for the vegetative phase of the tomato plants, during which they grow their leaves and stems. It also increases the mass and yield of tomato plants, but excess blue light causes the plant to be counterproductive. Tomato plants grown exclusively under blue light causes a reduction in photosynthesis.
 
Red Spectrum Light
Tomatoes need more red light than blue light. Red light is used more efficiently by tomato plants, and they need a large quantity of it during the flowering growth period. Tomatoes depend on the red light for the amount and quality of their flowers. Red light instills tomato plants to become more resistant to disease and environmental stress.
 
When growing tomatoes under full-spectrum lighting, make sure the red-light ratio is higher than the blue light. Remember that the “full-spectrum” of lighting mimics the sun’s natural lighting, and healthy tomatoes need the full artificial spectrum of light.