Nutrients I -- Nutrient Basics
Your plants are what they eat
By Scott Misener
There are three basic stages of growth - rooting, vegetative, and fruiting/flowering. When rooting cuttings or germinating seeds, very little nutrient is needed. In fact, too much nutrient will actually hinder the rooting process. Those first roots that pop are lined with delicate root hairs that you can't even see with the naked eye. An overabundance of nutrient will burn all those little hairs right off your plant and you will find yourself back at square one. A very light solution of seaweed and filtered water is all you need to provide your plants with enough nutrients to develop a root system to sustain the seedling's growth. Only when those little plants begin to take off and grow is it time to move the little plant to a soil container or hydro system.
If you are using new soil it is unnecessary to fertilize for the first couple weeks. Most potting soils on the market today are fortified with nitrogen and phosphorus in the form of earthworm castings and bone meal. Watering with plain water will wake up these nutrients, making them available to the plant. Over the course of a few weeks, nutrients will be washed or leached from the soil through the process of watering. That's when most people fertilize.
Now let's be realistic. Plants have been around a lot longer than us humans have, and they did just fine without regular applications of fertilizer solutions. Plants want to grow. Plants want to live and they will fight for it. What happens is that humans think they have all the answers, as usual. We pour all the latest concoctions dreamed up by a chemist in a lab into the tender environment that the root system calls home. The contemporary indoor gardener tends to make things more complicated than it needs to be. Be careful. This industry is gimmicky. There is another way of thinking. I have talked with a lot of people who just laugh at all the nutrient varieties offered today. They all claim to have had the best results when they used new soil and watered with plain water! No nutrients!
That argument works for soil, but not for hydroponics. Plants need more than just water in hydro systems because mediums used in hydro systems offer no form of nutrient. You have to provide everything they need. A successful feeding schedule begins with some basic understanding of nutrients.
There are many nutrient programs on the market today that range from simple one-part solutions to more complex programs that require ten or more components! A common thread to all these nutrient programs is that they are formulated as complete lines. You're setting yourself up for failure if you mix and match components from one company to another. For example, a popular nutrient on the market is Botanicare. Botanicare is essentially a four part nutrient program that consists of a grow or veg formula, a micronutrient, a bloom or fruiting formula, and a catalyst. When you use the grow and micro from Botanticare but choose to use the bloom formula from another company, let's just say Earth Juice's bloom, you run the risk of either doubling up on certain nutrients or missing out on crucial components altogether. In short, you will experience nutrient lockout and deficiencies, and a deficiency will just slow you down and stress your plants.
It may appear that nutrient manufactures are dividing the components on their nutrient lines to make the gardener spend more money, and that is probably true in some cases, but there is a legitimate reason for doing so. Almost everything you feed your plants are metals. If you throw all the metals together in a concentrated form in one bottle, they will grab onto each other. Those molecules will form a particle too large for your plants to uptake through the small openings in the root systems rendering the nutrient solution useless. In hydro this can be fatal for your plants.
Now say after me, it is better to starve your plants than to overfeed. Ponder this statement and come back next week. We have a lot more to cover on this subject.
Those three magical numbers proudly displayed on bottles of plant nutrients are the N-P-K analysis of that particular nutrient. If it claims to be food for plant, it has a N-P-K ratio. What does N-P-K stand for? I thought you'd never ask. The N, or first number in the lineup stands for nitrogen. The P, or second number, stands for phosphorus. And last, but just as important is K, or potassium, or potash as it is affectionately referred to.
Plants need all of these elements, or macronutrients, to successfully supplement all the rigors that plant development demands. The majority of plant feeding programs offered today involves one or more components that are fed at the appropriate plant developmental stage. The earliest phase of plant development is rooting. Cuttings and seedlings have similar needs. They both are caught in a sink or swim situation. In order to survive they need roots to uptake all those vital nutrients necessary for growth. Roots themselves are made up of potassium. Phosphorus aids in rapid root growth and gives plants the edge they need to make it to the next phase of growth - vegetation.
Nutrient manufacturers tend to formulate growth formulas that aid in both rooting and vegetation since the two growth phases run into each other. Nitrogen directly feeds a vegetative plant, so nitrogen levels tend to be higher in grow formulas. If you compare grow formulas, you will notice that they not only contain nitrogen, but also high levels of potassium at equal or higher levels. That potassium is for root development. More roots down below means more plant up top. They are directly related. To get those sizable fruits and vegetables, your plants need a large root system. Your roots are the lifelines of your plants. They search out and uptake all the nutrients your plants crave. Roots also expel wastes that accumulate within the plant. Keep your roots clean and healthy and your plants will be happy.
As the growing cycle progresses and your plants have achieved a manageable size and girth, the lights are cut from eighteen hours to twelve, thus inducing fruiting/flowering. Keep in mind that plants will almost double in size from the time you cut back the lights to the time they finish producing fruit. Be careful not to outgrow your garden space. A crowded garden only gives you headaches down the road!
The moment you cut back the lights, your plant's nutritional needs will change. The plant's diet is a factor in its response to the shortened light cycle. At this time, a plant needs less nitrogen and more phosphorus and potassium. Feeding programs alter the feeding schedule to fill these needs. This usually requires a mix or half grow and half bloom formula coupled with added calcium.
Calcium is a considered to be a micronutrient, but that is an understatement. Calcium is just as important as nitrogen, phosphorus, and potassium. In fact, the available calcium levels directly affect the phosphorus intake. Without calcium, plants can't process phosphorus. Fruits, vegetables, and flowers are all made of phosphorus. You see where I'm going. This is where a micronutrient formula comes into play. All nutrient lines on the market today have some form of a micronutrient, or micro. There is a lot more in that bottle of micronutrients than just calcium. Magnesium, iron, manganese, zinc, copper, boron, molybdenum, and cobalt are just a few elements that are considered micronutrients. Make sure your chosen micro has got them, because your plants need them! Micronutrients fill in the gaps in your plants diet allowing them to live up their potential.
After a week or so, the plants in your garden should be acclimated to their new light cycle. Now it's time to run with fruiting/flowering. At this time, grow formulas are cut out of the diet all together and you switch to a bloom formula. Bloom formulas offer higher levels of phosphorus and potassium. Nitrogen is cut down to a trace, just enough to supplement the vegetation that is to develop. Be careful with those nitrogen levels during the bloom cycle! High levels of nitrogen will work against you by promoting vegetative growth when the plant needs to be thinking about producing fruit.
There is another aspect of picking out plant food that you should be aware of, and that's the manufacturer's point of view. Rule of thumb: manufacturers of plant fertilizers will always recommend that you use more food than needed. They usually, and consistently, recommend you use about twenty-five percent more nutrients than required. Manufacturers push higher levels of nutrient simply to sell more product. That's it. When fertilizing, less is more. Do yourself, your pocketbook, and your plants a favor and keep it light. Your plants will thank you for it!
Another thing to consider are the N-P-K numbers. When fertilizer companies submit their nutrients to independent analysis to formulate those N-P-K ratios, they are only required to publish the minimum amount of N-P-K found in the nutrient concentrate. In a nutshell, this means there probably is more N-P-K in that food than indicated. They do this because simply because they want to tell us, their customers, what we want to hear. Do the research and ask your fellow gardeners questions. See what they had success using and how they used them. There are many different approaches to gardening and they all work. We are all learning. The day you think you know everything is the day you start to fall behind.