Farmers Lab Seeds Growers Guide
Whether you prefer to grow indoors or outdoors, indica or sativa, there are few things in life that are as satisfying as your very own, homegrown marijuana.
While to the novice it may seem like gardening is an annual task, completed in the spring for a bountiful summer harvest, it is actually far easier and more lucrative to maintain growing around the year. This guide will introduce you to the basics of maintaining a plant, from seed to weed, including the differences in growing indoors and outdoors, the necessary supplies, how to make the most of every season, and what to expect as you nurture and maintain your plants.
Genetics and the plant
When embarking upon your growing journey, it is important to keep a few things in mind to make certain you grow healthy plants with strong genetics. When selecting seeds, opt for local or reputable sources, so you can get a hardy plant, tailored for your individual climate. Getting the right seeds will ensure things like resistance to disease and pests, desired potency and aroma, and optimal growth.
Cannabis can be classified into two major types: Indica and Sativa. Indica plants, which give a weighty, body high, flourish in indoor settings and can be identified by their broad, rounded leaves. Sativa plants, which boast an airy, cerebral high, require much more light, making them challenging to grow indoors. Sativa plants can be easily identified by their slender, finger-like leaves. Additionally, there are strains which are Indica-Sativa hybrid. As the name suggests, hybrid strains look and feel like a combination of both Indica and Sativa. Once you know what to look for, distinguishing between strains can be done simply by observing the leaves.
As a beginner, the best place to start your growing journey is with a hybrid plant. Hybrids will flourish both indoors and outdoors, as they do not require as much light as a Sativa plant and will typically mature faster, a quality gleaned from the Indica plant.
When selecting seeds for planting, only use ones that appear dark brown or grey. Fine, dark lines set into the seed are normal, but avoid using seeds that are very small and white. This indicates that the seed is immature, and will yield an unhealthy plant, if they germinate at all.
To germinate seeds for outdoor planting, use sterile soil, and for indoor planting use a hydroponic medium. Avoid using jiffy cubes as some research has show peat cubes can stunt the growth of plants.
Keep your germinating seeds moist at all times, and do not allow light to reach them, as this can inhibit growth. Pots should be covered completely with black paper or kept in a light-proofed area. Transplant as little as possible, as transplant shock can also slow the growing process of a new plant. You can avoid this altogether by planting in rockwool.
To germinate a seed in vermiculite solution, cut a hole in the bottom of a 16 oz. cup and fill with vermiculite, then plant your seed and place the cup in a weak nutrient solution. To germinate a seed in rockwool, simply place a seed in a small rockwool cube, watering to keep it moist, and move your cube into larger slabs of rockwool as the plant grows.
To germinate a seed for outdoor growth, fill a sterilised pot with sterile soil. You can cut holes in the bottom of the pot for drainage and fill the top ½” with vermiculite to help start your seed. You can use a 5-55-17 soil blend to stimulate the root growth of germinating seeds and seedlings. Hydrate with a 1:3 mixture of nutrient solution and distilled water.
Your plant enters its vegetative growth stage as soon as it sprouts. Vegetative growth means your plant will be constantly photosynthesising, and growing at a rapid rate, and you will expose it to light around the clock. During this time, it will develop grow tips at the top of the plant, and at internodes. Grow tips can be trimmed for cloning or propagating asexually. You may choose to “top” your plant to produce two or more grow tips on the top, however the trauma from pruning can stunt your plant.
You can keep your plants in their vegetative growth stage indefinitely, simply by keeping them exposed to constant light. You will need to “force” your plant to flower when ready, and can continue growing your plant at an accelerated vegetative rate until it is the size you want. Use a 20-20-20 solution with trace minerals for plants growing continuously, whether growing hydroponically or in soil.
When plants are young, bend their stems back and forth to build resistance, as spindly, weak stems cannot support weighty flowering periods. If space permits, set up an oscillating fan in your grow area to reduce the buildup of moisture on the stomata and help build stem strength. Air circulation is incredibly important in your grow space as it promotes healthier growth and cuts back on hazards such as heat, humidity and accumulation of chemicals in the air.
Water plants using a hydroponic vegetative solution of 1 tsp. Miracle Gro Patio and ½ tsp. Epsom salts per gallon of water, and optionally add 1 tsp. of an oxygenating plant food. This ensures your plant gets a broad spectrum of nutrients and roots are well oxygenated.
Your plant is large enough to mature and flower when it has reached a minimum of 1’ in height. It is then up to you when you want to force it into flowering and fruiting. To move your plants to this stage, you will begin a dark cycle of 11-13 hours of uninterrupted darkness per 24 hour period.
If you are growing outside and want to force plants into flowering for a summer harvest, you will need to cover your greenhouse with a blanket to achieve a long enough dark cycle; if you are growing indoors you will need to put your lights on a timer. If you choose to keep your plants on a 13 hour light, 11 hour dark schedule, your plants will produce larger flowers, while reversing these hours will speed growth.
DO NOT allow regular light in your grow space during the dark hours. Any amount of light during this time will delay flower development. If you must work in your grow space during your dark time, you can set up bulbs that emit only green light, as these will not trigger the release of hormones that regular light does.
During the flowering stage, water plants with a hydroponic flowering solution consisting of 1 tsp. high-phosphorus plant food, ½ tsp. plant food and 1 tsp. trace element plant food. This will provide plants with essential nutrients for a hearty crop. Feed plants with every watering for the first week of flowering, then move to every few waterings.
Prune minimally throughout the flowering stage, as the growth of plants has slowed and you may stunt or traumatise the plant. Spray flowering plants minimally as this can promote rot and contaminate your harvest. Minimise humidity in your grow space during this time as this can encourage mold and rot.
After a week or two of keeping your plants on a light/dark schedule, you will notice the early stages of flowering. This is when you will be able to differentiate between male and female plants. Females can be identified by the emergence of white “hairs” from bulbous areas around each internode. It is at this time that you will want to pull all the males from your grow area.
Three to six weeks into your plants’ light/dark cycle, your plants will have white pistils growing at every grow tip. These are mature flowers, and when you feel your plant has a sufficient number of them, you can adjust your light cycle and prepare for fruiting.
When you are ready for your plant to fruit, you can reduce the light time to 8-10 hours to ripen plants quickly, and have a harvest ready within three weeks. You may also choose to keep plants on a 12 hour cycle throughout the flowering and fruiting stages, which will slow ripening time but increase overall yield.
You will know it’s harvesting time when the white pistils on the plant change from white to shades of red, orange or brown (depending upon the strain). When more than 80% of the pistils have turned, and the false seed pods are swollen with resin, you can begin picking the buds. Remember not to touch the buds themselves, as the THC crystals will stick to your fingers and reduce potency of your yield. If you need to inspect buds, handle plants by the leaves
Year-round harvesting – Indoor & Outdoor
For a cost-effective, energy-smart method of farming, the best solution is to start seeds indoors, where they will remain throughout the germination and vegetative growth stages, and then move them outdoors for flowering. This will make use of the natural light/dark cycle outside, and cut down on your energy usage significantly.
Year-round production is made possible by the two growth cycles of the cannabis plant. At germination, the plant enters what is known as a vegetative state, which means that it makes use of continuous light and is constantly photosynthesising. Keeping your plants indoors during this phase will allow them to grow faster than they would outdoors, as the dark of night will interrupt their continuous growth cycle.
The growing process is best started in Winter, when you will want to utilise your indoor space for nurturing seedlings and/or cuttings. Beginning indoors in Winter will help you avoid stunting plant growth that the long nights and short days can cause.
In Spring or Fall, when plants reach 12”-18” in height, they can be moved outside to take advantage of the lengthening days and uninterrupted darkness at night. Moving the plants from continuous light to a light/dark cycle will force the plant to flower, and will yield a harvest within 2-3 months.
For the outdoor stage of growing, you will need to construct a small greenhouse. This can be done quite simply using fibreglass or plastic sheeting, and will provide the plants with optimal growing conditions and allow you plant directly in the ground. It will also protect your crops from pests, harsh weather and prying eyes.
For indoor planting you will need to find a small space, such as a closet or spare bathroom, that can be closed off and independently ventilated. Ventilation can be as simple as leaving the door ajar, provided you are not using supplies which generate excessive heat, but it is best to have separate air intake/exhaust outtake.
The first step in preparing your grow space is establishing ventilation. You will want to set up air intake from an outside source, and an outtake vent that will push hot, stale air out and away from your grow room, preferably outside. This can be done quite simply using 4-6” PVC pipes, silicon caulking and fans from old computer towers.
The second step you’ll need to take is lining or painting the walls. In order to diffuse light and prevent hot spots, line the walls with either aluminum foil (with the matte side facing out), aluminised mylar, or paint the space bright white. Do not use mirrors as the glass will absorb heat, which is quite the opposite to the desired result. During this time you will also want to cover any cracks and windows.
Third, you’ll want to protect the flooring from spills and grime by laying down plastic sheeting. Ensure the electrical outlets you’ll be using can handle an adequate amount of voltage for the lamps you’ve chosen, and invest in a surge protector for the space. Make space for lamps and other electronics on a shelf to keep them off the ground and away from potential spills. While you are arranging your shelving area, consider leaving and additional space for things like plant food, spray bottles and other supplies, so that they’re always close at hand and not in the way.
Finally, you will need light. If you are starting plants indoors, to be transferred outdoors for flowering, a few shop lights will be adequate. You’ll want one cool white bulb and one warm white bulb to generate the most complete spectrum of light possible.
For an easy, inexpensive indoor operation, shelf growing with fluorescent lights is the way to go. This method consists of a shelving unit with a fluorescent bulb on each shelf, which can save you a ton of space if you’re working with a small area. You can have a complete growing operation using just two shelving units, one with 24 hour light and one with 12 hour light, for flowering. Additionally, shelf growing means that your plants are kept to about three feet in height at maturity, which in turn means you’ll be using less energy, as smaller plants do not require as much light to thrive.
The downside to shelf growing is that the operation requires more maintenance than other methods of growing, because shelf-height and light-height have to be adjusted constantly as your plants grow. Plants should be kept within 2” of the light source, however, during vegetative growth, plants can grow up to an inch a day, which makes it difficult to leave them unattended for more than a few days.
To set up your shelf growing space, you will first need to find an open shelving unit that is between a foot and a half and two feet wide. The shelf and the surrounding areas will need to be painted bright white or covered in aluminum foil, just like any other indoor growing space. This will reflect light and diffuse hot spots. You can fix sheets of aluminium foil, aluminised mylar or foil blankets to enclose the sides of the shelf, if covering the surrounding walls is not an option.
For lighting, you will need to suspend shop lamps above the area on the shelf where you intend to keep your plants. You want the lights to be around 1”, no more than 2” away from the tops of the plants at all times. If the light source is too far away from the plants they will “reach out” to the light, growing spindly and subsequently producing less bud at harvest time.
Shelf growing is also the easiest setup for the “sea of green” method of farming, which means producing a large quantity of small plants, matured quickly, to get a large harvest in the shortest time frame possible. In theory, you will use the same amount of space as you would with a few large, slow-growing plants, but by keeping plants small and maturing them faster, you will significantly cut down on the time between harvests.
Plants grown outdoors tend to be more robust and more evenly developed, as they are exposed to natural sunlight, and the light can reach more of the plant. While growing out in the open exposes your crops to pests and the elements, greenhouses are easy to construct and create the perfect growing environment.
When finding a location for your greenhouse, you will want to choose somewhere that gets at least 6 hours of full sun in the winter. Construct a an innocuous “shed” using plastic sheeting, PVC, filon or glass that has been opaqued using white-tinted epoxy resin or lime. You only need one wall and the roof to allow sunlight–the rest of the walls can be a completely opaque material. Within your greenhouse you can choose to set up a hydroponic system, or plant directly into the ground.
If you choose to plant directly into the ground, with or without a greenhouse, you will need to start by digging a hole large enough for the roots of a fully-grown plant. You can then either fill the hole with an optimal growing medium, or place large pots into the holes for easy transport of the plants.
Your nutrient solution should be a blend of soil and fertiliser, and sit at a pH of 6.2-6.7. Before planting, invest in a pH meter to test the soil, and monitor it throughout growth. Before planting, correct alkalinity with phosphoric acid and acidity with lime or potash. If your solution becomes too acidic over time, which tends to happen with the breakdown of fertiliser in the soil, you can leaf feed your plant to ensure it still gets the nutrients it needs (see Foliar Feeding).
Perhaps the most important step in setting up your indoor growing space is selecting the right lights, to ensure your plants will thrive. The absolute lowest output you’ll want to use is 2000 lumens per square foot. Any lower than this and you risk stunting plant growth, and increase the chances of growing plants that are all stem and little bud.
Optimal output for your lighting is 2500 lumens per square foot, 3000 if you are using soil enriched with CO2. The best way to achieve optimal lighting is using High Intensity Discharge lamps, of which there are three main varieties: High Pressure Sodium, Mercury Vapor and Metal Halide.
High Pressure Sodium (HPS) bulbs are by far the most efficient of the three varieties of HID lamp. A 400 watt HPS bulb has an output of roughly 45000 lumens, and can be used constantly throughout every stage of growing. As well, the spectrum produced by HPS lights is high in red light, so it produces above-average results during the flowering stages of growth.
Metal Halide (MH) bulbs have demonstrated faster crop maturity than HPS bulbs, but with smaller yields. A 400 watt MH bulb will output 36000 lumens, and again can be used throughout the growing process. The spectrum produced by a MH bulb is high in blue light, which accelerates growth during the plant's vegetative growth stage.
Mercury Vapor (MV) bulbs are inferior to MH and HPS bulbs in both efficiency and light output. MV bulbs are similar in output to fluorescent bulbs, however you are not able to position them as close to plants as with fluorescent bulbs, so there is an increased risk for stem-y plants and below-average harvests. A 400 watt bulb will generate 20000 lumens (compared to 30000 by a fluorescent bulb of the same wattage), and produces a blue-toned light.
When setting up your lighting rig, aim to position the lights horizontally above the plants, as opposed to lighting them from the sides. This will increase the amount of light that reaches the plants and ensure that plants are lit evenly. Consider the size of the space you are working with, and make sure to choose an appropriately sized lamp for your growing area. HID lamps generate an excessive amount of heat and using a lamp that is ill-suited to your growing area will make constant ventilation a necessity.
Plants grown using a hydroponic system have demonstrated accelerated growth, due in equal parts to the additional nutrients the plants are provided with and the increased oxygen levels present in the growing medium. The simplest methods of hydroponic growing are the wick method and the reservoir method.
The wick system is established by first setting up a water reservoir. You can use buckets, which your plant pots will sit atop, or use something larger, such as a kiddie pool, with bricks laid out to keep the plants above the surface of the water. Fill the reservoir with 1 ½”-3” of watering solution. Next, you will need to prepare your pots by cutting holes in the bottom and threading a wick (eg. strips of felt, rope) through each one. Pots are then filled with the hydroponic growing solution and positioned up and out of the water, while the wick sits in the reservoir.
By comparison, the reservoir method is much simpler to set up, and uses less vertical space. All you will need a pan, such as a mid-sized Rubbermaid bin or kitty litter box, and an appropriate medium, such as rockwool. Fill the bin with a slab of rockwool, and plant directly into it. Water and feed plants by pouring your solution directly into the reservoir every few days.
Rockwool is a valuable resource in hydroponic growing as it eliminates the need for transplanting. It is a planting medium that replaces soil that can hold 10 times the amount of water soil can, while naturally preventing overwatering. To plant in rockwool, first pre-treat with a 1:1:1 mixture of fish emulsion, trace mineral solution and phosphoric acid for 24 hours. This will help neutralise the pH of the rockwool, which is naturally a 7.7 and far too alkaline for planting. If you choose not to pre-treat, you will need to add vinegar to your nutrient solution to keep the pH lowered. When the rockwool is prepared, place your starter cube into a larger rockwool cube, then place that cube into a larger brick of rockwool when your plant is large enough. Rockwool can be reused, creating a stable, controlled growing medium for crop after crop.
For a traditional hydroponic soil solution, use a 4:1 mixture of rinsed lava rocks or pearlite and vermiculite. Add 1 tbsp. dolomite lime per gallon of growing medium. First, fill pots with rocks, wet the vermiculite and combine. Make sure there is a higher concentration of vermiculite at the top of the pot, as you will need to water from the top occasionally to leach mineral deposits, and this will cause the vermiculite to shift towards the bottom of the pot.
*Always wear a mask while handling dry vermiculite, as it is highly toxic; vermiculite is not recommended for use indoors or in confined areas.
Administer plant food with most waterings, to carefully control the flow of nutrients to your plants through each stage of growth. You can take advantage of simple drip watering systems when possible, but your plants will be much stronger when taken care of properly.
Hydroponics require careful attention throughout the growing process, and must not be allowed to dry out. Allowing roots to get too dry can damage them, and if left for too long you will lose your crop. To avoid this you can fill your reservoir as full as possible, but it is much better let the water in the reservoir recede between fillings. Opt instead to water more frequently while using less solution. This allows the roots of the plants to pull in a greater amount of oxygen.
Cationic changes in the watering solution will cause it to become more acidic over time. If you notice a significant or rapid decline in the pH of your solution, you need to change it. Plants left in an acidic solution are deprived of vital nutrients and you could stunt or lose your crop.
If you are growing in a space with high humidity, you may notice the formation of algae in your medium. While it is an unsightly nuisance, it will not damage your crop in any way. You can eliminate the potential for algae growth by layering gravel on top of your soil medium, or if you are using rockwool, by covering your slabs with the plastic sheeting the rockwool came in.
Foliar feeding refers to spraying the leaves of your plants with a nutrient-rich tea, and is a simple way of aiding plant growth and increasing both the yield and quality of your harvest. It is best used when growing in a well-ventilated space, such as outdoors. Foliar feeding should be done throughout the vegetative growth stage, and into early flowering, but should be stopped two to three weeks before harvesting to avoid tainting your finished product.
Your foliar solution should be a combination of your plant food of preference and water, and have an optimal pH level between 6.2 and 7. If the pH is too high, add vinegar to increase acidity; if the the pH is too low, add baking soda to increase alkalinity. You may also choose to add soda water to your solution, which will introduce CO2.
Foliar feeding is best done in the early morning and evening, due to the cooler temperature and lack of direct sunlight. You want the temperature to be around 72 degrees, because the stomata of the plants will be open and able to absorb the solution. You must make sure to wash the leaves of the plants with water at least once a week to prevent these stomata from clogging. It is important to find a spray bottle that will produce a fine mist, as you do not want to drench the leaves of the plant. Ensure you never spray while the leaves of the plant are in the sun, as this can cause them to burn.
*If you choose to foliar feed, it is imperative that you wash the leaves of the plant thoroughly before they are harvested, to ensure you are not consuming plant food.