Growing specialty plants indoors in a growing room is a science and an art. Plants such as orchids, violets, and other specialty crops will thrive in a controlled environment.
Some people who started out as amateur home gardeners now have an indoor gardening business growing orchids and other high value plants.
These plants need proper environment, handling, and nutrients if they are to thrive. The following guide is presented as concisely as possible, but is no substitute for other types of research that growers should conduct.
Please note that the information presented is targeted towards indoor growing using soiless methods. This means that rockwool, volcanic rock, coco coir and other sterile media is used for the root zone- instead of soil.
Using sterile media gives you the ability to control every input that goes into your crop. But it also means you have to properly administer quality nutrients, because there’s no other way for plants to get what they need.
For converting measurements used in the following text, consult this handy website: www.sciencemadesimple.com/conversions.html
Climate Temperature Range:
During lights-on cycle, between 70 and 80 degrees Fahrenheit. During lights-off cycle, between 64 and 71 degrees Fahrenheit.
Ideal day cycle growing temperature without C02 augmentation: 73 degrees Fahrennheit/23 degrees Centigrade.
Ideal day cycle temperature with C02 augmentation: 76 degrees Fahrenheit/24.5 degrees Centigrade.
(Note: Centigrade is the same as Celsius).
Root Zone Temperature:
68 degrees Fahrenheit. Growers with plants in pots growing in basements or cement slabs should not put their pots directly on the floor, as this can cool the root zone too much. If a root zone is too cold, it can harm roots and slow growth rate.
Water/Nutrient Solution Temperature:
66 to 71 degrees Fahrenheit.
Grow Room Humidity:
40 to 65% during vegetative phase; 40 to 60% during flowering. Excess humidity creates conditions that allow mold and other harmful organisms to flourish.
Vegetative Growth: 18 hours on, 6 hours off. (Studies have shown that 24 hour light cycles cause no more growth than 18 hour light cycles.)
Floral triggering and flowering growth: 12 hours on, 12 hours off. (May vary due to type of plant being grown and other factors).
Types Of Lighting:
Early cuttings and clones: Fluorescent lighting.
Vegetative Growth Cycle: Metal halide and High Pressure Sodium, augmented by vertical fluorescents for side growth.
Preferred vegetative growth lighting ratio: 60% Halide, 40% HPS.
Lighting for Floral Growth: High Pressure Sodium Only, No Metal Halide.
For stationary lights: One 400 watt bulb provides adequate light for 10 square feet of space. One 1000 watt light provides adequate light for 20 square feet of space. The use of light movers can extend these coverage areas.
Light output is measured in “lumens,” using a lumens meter. This is a handheld device that responds to light in a fashion similar to how a cameras light meter responds to light. The top of the plant canopy should be receiving 3000 lumens.
Use the light meter and visual inspection to determine where inadequate light levels are occurring. Usually, these low light areas will be in corners, and at the bottom of plant canopies. Unequal lighting will result in unequal growth patterns, and loss of yield.
This bounces light back into the plant area, resulting in better growth.
The best reflective materials are Mylar or white glossy plastic. This should be placed on all walls and on the ceiling.
Aluminum foil, mirrors, and white paint do not have adequate degrees of reflectivity.
Distance Of Plant Tops To Lights:
If plants get too close to high intensity lights, it can severely damage them.
Metal Halide and High Pressure Sodium bulbs, if not separated from plants by glass or other material between bulb and plants, should be 2.5 feet from top of plant to bottom of light.
Fluorescent or glass-shielded MH/HPS should be one foot from plant tops, but it is important not to take for granted that this is an adequate protective distance. You still need to closely monitor temperature at leaf zone to prevent burning. The temperature at the point of the leaf zone closest to the lights should never exceed 84 degrees Fahrenheit.
Sterile Grow Media:
Rockwool, processed coconut husks, lava rocks, vermiculite, coco coir, perlite, perlite, clay pellets.
Plants need large amounts of oxygen, especially in the root zone. If you want the maximum amount of oxygen in the root zone, you should read the aeroponics article on this website and consider installing an aeroponics system. Aeroponics maximizes oxygen in the root zone, which results in faster growth.
Plants grow best when they have large amounts of carbon dioxide (C02), especially at underside of leaves.
Total room C02 should be 1500 parts per million, but natural levels of C02 are approximately 400 ppm, so C02 augmentation is recommended, especially in above average temperatures.
The C02 emitter should be timed in relation to exhaust fan so that C02 is not sucked out of room.
Air Circulation (Inside Grow Room):
Circulation by at least one medium size oscillating fan for any size grow space, no matter how small.
For larger grow spaces, at least one medium size oscillating fan for every three 1000 watt lights. Adequate aeration occurs when you can feel air movement in your grow space at plant level- so that all plants are in a moving ocean of air.
Install exhaust fan(s) sufficient to totally exchange all air in grow space every five minutes. Exhaust fans must be timed relevant to C02 augmentation to avoid removing augmented C02 from room.
For orchids and other plants, you can often trigger flowering by changing light cycle to 12 hours on 12 hours off.
After this change, plants should show changes within two weeks.
Important note: during the dark cycle, do not let any stray light enter the growing chamber, unless you use a low-wattage green-colored light bulb for short periods of time for necessary chamber illumination. Stray light can confuse plants and cause mutations in flowers or delay flower maturation.
Ideal Ph Of Grow Media And Nutrient Solution/Water:
Between 5.8 and 6.3. pH higher or lower than this range can interfere with plants ability to uptake nutrients.
Ideal Ph Of Root Zone Media:
Ideal Ppm (Parts Per Million) Of Hydroponic Nutrient Solution:
For rooted clones, established seedlings, or mature plants in vegetative and flowering phase, between 1000 ppm to 2000 ppm, depending on strain, grow media, and plants growth phase.
Building Template For Closed Environment Grow Space:
Hydroponic Growing Methods:
The reason that Advanced Nutrients products are better than fertilizers made by other companies has to do with our company’s understanding that plants need proper nutrition so they can build healthy roots, stalks, stems, leaves and flowers.
There are 24 elements essential to plant life. Carbon, hydrogen, and oxygen are absorbed from air and water. The remaining elements are absorbed primarily through roots and must be provided by hydroponics gardeners.
When Advanced Nutrients set out to create fertilizer products, our only goal was to make products that most efficiently delivered nutrients to plants.
Advanced Nutrients scientists discovered the precise ratios and types of macronutrients, micronutrients and trace elements that would make the healthiest plants, such as amino acid proteins, beneficial microbes, enzymes, hormones and other substances necessary in soiless applications.
Further, our scientists found that other company’s products contained inferior versions of key substances. This problem is often related to chelation, a chemical process that greatly affects how easily plants can uptake nutrients.
Further, our products complement each other. Advanced Nutrients products work synergistically, so that each individual product combined with others to produce a dynamic, value-added plus.
The only way to ensure proper nutrition is to use the Advanced Nutrients engineered growing program, which is the only fertilizer and supplement program tested, designed and guaranteed to produce healthier hydroponics plants.