What Nutrients Are Needed for Hydroponics?

What Nutrients Are Needed for Hydroponics?

What nutrients are needed for hydroponics? It’s an important question—and one that has bearing on the health and heartiness of your future crops. Watering, lighting, and even trimming and cleaning your plants and system are easy steps. But whether you’re a rank beginner or a long-time grower, knowing how to best feed your plants, what nutrients to give them, and how much is still a tricky issue. Here's a basic guide to hydroponics and plant nutrition, as well as some tips for ensuring your grow is getting the goods.

What Are the Most Important Nutrients?

Like any organic creatures, plants are reliant on a certain collection of chemicals and other stuff to grow, survive, and thrive. The core list of basic nutrients is as follows: calcium, magnesium, nitrogen, potassium, and phosphorus. Other nutrients, such as boron, chlorine, copper, iron, manganese, molybdate, sulfur, and zinc may be required in some measures; but every plant, at some point in time, requires the previous list of five nutrients. Fortunately, you don’t need to be a scientist to use pre-mixed plant food for hydroponic gardens. All are available in premixed solutions and powders you can easily add to your system. But what does each nutrient do for your plants?

A Job for Everyone

Obviously, different nutrients do different things. Here are the basics:

  • Calcium—In the same way it builds strong bones in growing human beings, calcium helps create stronger support structures in plants, holding cells together. Without calcium, plants will experience cell death, leaves will curl, and buds and root tips will die.
  • Magnesium—Magnesium is integral to chlorophyll. When magnesium is absent, the chlorophyll in a plant will deteriorate, causing leaves to turn yellow. In plants with magnesium deficiencies, growth is inhibited, and any fruits produced will be poor.
  • Nitrogen—Skimping on nitrogen can cause plants to grow more slowly if not shorter, and leaves may fail to grow at all. Plants lacking nitrogen will turn pale or yellowish before finally wearing out, drying up, and turning brown.
  • Potassium—A lack of potassium manifests itself in the leaves of your plants. It’s recognizable by curling as well as a brown to yellowish discoloration. Once again, plant growth is inhibited, roots fail to grow, and the production of fruit and seeds is eventually drastically reduced.
  • Phosphorus—Plants not getting enough phosphorus? Once again, growth won’t just happen. Expect the leaves to become discolored while their stems grow weaker and thinner, and forget about healthy flower, seed, and fruit production.

Fear not; by adding proper nutrients to your system, as well as carefully monitoring for warning signs, you can ensure your plants grow big, healthy, and strong while producing a bumper crop of your choosing.

Essential Nutrient Additives To Use With Every Grow

Multiple brands and mixes are available, but it comes down to one question: what do you want to grow? No matter what type of plant you are growing, it’s always important to have Cal Mag in the mix, especially if you are using LED lights. We recommend our selection of Cal-Mag plant food and supplements, which are specially made to address mineral deficiencies in plants. This mix is very soluble, breaks down quickly in water, and addresses the quality of specific grow media like coco coir, which can remove some of the calcium and magnesium from a solution. Cal-Mag plant food also helps to prevent plant diseases throughout the lifecycle of a plant.

Overall, for most hydroponically grown plants, go with a nice mix of nitrogen, potassium, and phosphorus, calcium nitrate, and magnesium sulfate during your growing season. Follow the instructions given on the label for proper mixture and administration of the supplement.

In the Mix

Before you start creating your solution, consider the material used to create whatever container you're using to mix things up. Plastic jugs and tubs should be safe, but ensure they’re clean and sterilized, so nothing unpleasant enters the solution. Also, some chemicals in plant food can irritate the skin or eyes, Buy and wear a pair of rubber gloves and goggles to protect yourself. If you’re adding the solution to a container you can hold in both hands, be sure it has a cap so you can shake it thoroughly without spilling. If you're doing the mix in a large open container, use a wood stick or large and long wooden spoon to stir it all together. This will take more time but will also allow you time to adjust and be thorough.

Speaking of, how’s your mixing technique? If you’re worried about getting the measurements right between different nutrients, there are premade liquid solutions you can add to water and administer to your hydroponics system. If you’re more hands-on, purchase a measuring scoop and scale to properly gauge and weigh the amount of each nutrient before adding it to water. Honestly, using powders saves you money and allows you to be a bit nimbler in addressing nutritional issues as they occur. Slowly add ingredients, one by one. Measure the pH of the solution afterward, in case you’re having problems with maintaining pH levels.

Incidentally, hold off on using tap water straight from the faucet. That water is intended for drinking, cooking, and bathing, and has been treated to kill bacteria, remove toxins, and provide tooth-strengthening fluoride. While that’s good for humans, it may hurt your hydroponics system or plants. If you do use tap water, let it sit outside in the sun for a day to remove the chlorine. Rainwater is your best source of hydration, but that won’t always be available, so tap water, with treatment and after being tested for its pH levels and PPM of chemical content beforehand, will do in a pinch. Also, as a side note, letting your water sit and achieve room temperature won’t shock the roots of your plants with a suddenly chilly dip. Some plants can thrive on chilly water, but most grown hydroponically don’t.


Now that you know what nutrients are needed for hydroponics, now you need to keep an eye on them in the coming weeks. Continue to monitor pH and other levels, adjusting levels as needed. You’ll need to replace the solution every two to three weeks as well, so make and post a schedule to remind you. Finally, when your season is done, it’s time to clean out the system, sterilize it, and start all over again!

What Nutrients Are Needed for Hydroponics?

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