There’s a wide array of hydroponic nutrient products on the market these days, and manufactures have even come up with complete feeding schedules for entire lines of the nutrients they sell. As growers we naturally want to give our plants the best of everything, but this can sometimes do more harm than good. Most of the time the dosing rates that manufactures give, are recommendations for the stand-alone application of their products. They simply can’t account for anything, and/or everything else you might use (additives, biological inoculates, etc.). It’s important to pay attention to the overall feeding strengths, it all contributes to the overall feeding strength of the nutrient solution, and how the plants react to it. Also the growing environment itself will affect how suitable the feeding strength for your plants will be, and subsequently how the plants will react to it.
Growers often refer to their nutrient strength in PPM (parts per million), although EC (electrical conductivity) may be a better way to measure it. EC is the base measurement that PPM is converted from, and PPM is not universal. Different manufactures in different regions use different conversion rates, that will affect what the actual PPM should be, while EC will remain the same from one region to another. In most cases it’s rare for the EC of the nutrient solution to need to be higher than 2.0.
The best bet is to just fallow the feeding schedule of one reputable manufacturer at a time. Piecing together a custom feeding schedule using different manufactures products can be quite a hit and miss endeavor. Over-fertilized plants tend to produce poorly, and are much more likely to be affected by diseases and insects. They also don’t usually smell and taste nearly as good either. Along with keeping an eye on the overall strength of the nutrient solution, flushing the growing medium with plain water a couple of times a month will help keep nutrients from building up in it and causing problems.
Grow Room Temperature
When growing indoors it’s usually necessary to use at least some artificial hydroponic lighting, and with the technology today there are a wide variety of lighting options (bulbs, fixtures and systems, etc.) available. Most widely used are High Intensity Discharge (HID) lights, also known as Metal Halide (MH), and High Pressure Sodium (HPS). The larger wattage the bulb the more light, and generally speaking, the better plant growth will be. However these lights (as well as all the components of the lighting system) create heat.
MH and HPS lighting systems produce a lots of heat, this heat needs to be properly managed in a way to continuously maintain the optimal temperatures for your plants. Environments that are to hot and/or dry will stress the plants, and stressed plants just won’t produce well. For most indoor growing situations the plants will produce better, and have better quality when the temperatures don’t reach above 85°F at the tops of the plant (nearest to the light, and heat source). Some of this heat can be vented from the lights using ducting with inline hydroponic exhaust fans, and/or using fans directly on the plants, or even by adjusting the height of the lights.
For most plants (plants that don’t like high temperatures), temperatures above 90°F tend to result in poor crop quality in indoor (and outdoor) gardens. Higher temperatures cause the plants to work at higher metabolic rates. This causes all the plants biological processes to be accelerated. Just like a person that’s running, his/her body is more stressed, and will have accelerated metabolic rates than they would be if they were just walking. Plants are the same way, and wont function as well under stress. Then if one factor is lacking, like say oxygen levels to the roots, that compounds the stress level for the plants. Then if even just one important component is lacking, this could cause irreversible damage to be done. Even if it means using less light for your plants, keeping the temperatures at the optimum will reduce the plants stress level, and be beneficial to them.
Root Zone Temperature
Along with the plant canopy, pay attention to the temperature of the nutrient solution and root zone. The temperature of the root zone can be a unnoticed area that will greatly affect your plants. High and low temperatures in the root zone will also will stress out your plants. The optimum temperature of the nutrient solution is between 68°F and 75°F, and if the nutrient solution is in the optimal range, then your root zone will likely be in that range as well. Low temperatures in the root zone inhibit the plants from being able to get the nutrients they need to grow and be healthy. High temperatures in the root zone cause heat stress. Think of it like hiking in the desert on a hot day and being allowed to drink all the water you want, except that all you get to drink is hot water. Just imagine how refreshing that would be.
Distribute the Light Evenly
If your growing with MH and HPS lighting, use a high quality hydroponic reflector in order to maximize your lights efficacy. High quality reflectors will spread the light more evenly, and give you better light distribution. Even light distribution is important when growing inside, you don’t want one plant directly under the bulb to hog all the light, and the other plants to suffer from pour lighting. Look for reflectors that have charts that illustrate how the light is distributed, and choose a reflector that’s designed for the wattage bulbs your using. In some cases where there is a large area to cover, it may be better to use more smaller wattage bulbs that are spaced evenly around the plant canopy. If you have any concerns about weather your plants are getting the light they need, it may be worthwhile to invest in a light meter. A light meter can tell you exactly how much light the plants are getting at various points around the plant.
Get to Know your Plants
Pay attention to your plants, if your plants are not ready for increased feeding strengths or the next growing phase, you should wait until they are. Fallowing recommendations is a good start, but plants don’t know there supposed to grow according to a chart. Just because a chart says at 3 weeks you should change the nutrients from vegetative to bloom, doesn’t mean there ready for that. Environmental conditions are a big factor on how fast they actually grow, so that’s a big factor on when there ready for changes.
Determining when the plants are ready for the next phase of growth, as well as increased feeding strengths can take a couple of trial and errors to get right. Especially if it’s a plant variety that your not familiar with. Some plants grow much more once flowering has started, and others slow down or even stop growing after it starts to flower. So knowing when to induce flowering will be a factor on how productive they will be. If your unfamiliar with a particular plant, do some research on them and ask people who have grown them before about the in’s and out’s of growing them. Even if they are only used to growing them in soil there incite will be helpful. Typically hydroponically grown plants will develop at a faster rate than soil grown plants, but still grow the same way. Getting to know your plants is important.
Experimenting with your Plants
Sometimes when trying to be a better grower, or figure out a problem, we try to do to much at once. It’s fine to experiment with crops, but it’s not much good unless you can accurately evaluate the results. When experimenting with your plants be careful not to try more than one variable at a time, and allow sufficient time to see a change before coming to a conclusion about it. If you change a 400 watt bulb to a 600 watt bulb, and introduce a additive to the nutrient solution about the same time, you wont know how much if any change was due to each variable. If you are experimenting to find the optimal temperature for your plants and, change bulb wattage and/or lighting cycles, feeding schedules etc., again you wont know what change did what. Start with a tried and true method, and experiment one variable at a time to dial it in accurately.
Plants need Love and Attention Too
Have you ever heard the term “made with love?” Well your plants need love and attention too, probably even more so. They cant speak, so they cant tell you when there suffering from disease, or stressed out from the environment. They cant even tell you if there being attacked by insects. They silently sit there suffering, and just try to do the best they can. However spend enough time with them and you will be able to notice the suttle signs they give when there unhappy, you will also be able to tell when there as happy as a songbird on a nice day with no cats in sight.
Most people garden because they love to do it, and/or have a passion for the particular crops they grow. We all have our good and bad days but if tending to your gardens becomes a chore, and your just in a hurry to get done tending to them, your plants will know it. If you just need more time to get other things done, you can enlist a trusted friend to tend to your plants part of the time. That would allow you to slip away for a while for other things, and the plants wont be neglected. Beer and pizza usually works on my friends.
Consider using beneficial’s
Weather you garden hydroponically or in soil consider adding beneficial microbes. These beneficial microbes add a layer of protection against pathogens and disease. They also use the growing medium as a breeding ground to reproduce and increase their numbers, much like a like a Bio-filter further protecting the roots. There are some beneficial’s specifically designed to inoculate hydroponic systems (works in soil as well), like bacillus, Pseudomonas, Trichoderma Fungi, and Mycorrhizae fungi. These are available in both liquid and dry form, and specifically formulated for hydroponics they wont clog up your hydroponics systems.