Everything You Ever Wanted to Know About Hydroponic Crop Processes

Hydroponic systems have gained popularity as a sustainable alternative to field farming for the process of cultivating crops.

Hydroponics isn’t a new idea.

The Hanging Gardens of Babylon were thought to have operated with a hydroponic system and evidence of floating gardens existing in early China and Mexico has been discovered.

These processes for growing crops are commonly used today for vertical and container farming because they don’t require things like fields, soil, or authentic sunlight. In this article, we’ll learn about the process of growing crops using hydroponics systems.

Basics

The word hydroponics is a combination of two Greek words, literally translating to “water labor”.

Farmers who use hydroponic systems to grow crops rather than traditional fields rely on nutrient solutions and growing mediums rather than fertilizer and soil.

Nutrient solutions are added to water to give it a high concentration of essential nutrients. That water is then delivered to the plants to replace the food they would’ve gotten from soil.

The goal of soil-less systems is to make it as easy as possible for plant roots to soak up the water, oxygen, and nutrients needed for strong, healthy growth.

Different types of soil-less systems use different processes to grow crops.

Hydroponic systems use a growing medium, like stones or sand, and a nutrient solution. In these systems, nutrient-rich water is delivered directly to the roots by soaking the medium.

In aeroponic systems, another common soil-less growing method, plants have their roots misted directly with the nutrient solution.

Our Pure Greens container farms use hydroponic systems in repurposed shipping containers to provide an easily-controlled, sustainable environment.

Reasons to Start Container Farming

Plants grown in hydroponic systems save space, time, and water.

Because neither fields nor soil is required plants can be grown vertically and closer together. They’ve also been shown to grow faster in hydroponic systems than in fields.

Even though these systems use water as the primary source of nutrition, hydroponics uses less of it!

Water in fields is lost to evaporation and run-off dispersion while soil-less systems provide water directly to the roots. Plus, water can be reused in hydroponics.

Types of Hydroponic Systems:

Different types of hydroponic systems use different processes to grow crops.

The four major classifications that describe hydroponics systems are passive, active, recovery, or non-recovery.

Hydroponic farming can either use passive or active systems for stimulating plant growth.

In passive systems, plants are almost constantly soaked in nutrient-rich water while rooted in a growing medium.

In active systems, pumps and tubes circulate water through the growing medium, flooding and removing water as needed.

Passive systems are easy for beginners but don’t offer nearly as much control as active systems.

The other two classifications are recovery or non-recovery, also known as recirculating and non-recirculating.

Recovery systems circulate and reuse nutrient solutions while non-recovery systems don’t.

Hydroponic systems that use a recovery process conserve more water than their non-recovery counterparts because the water doesn’t have to be pumped fresh.

Popular types of hydroponic grow techniques include the wick, ebb and flow, and continuous drip systems.

The wick system is passive and non-recovery. In this process, plants are grown in a separate container above a reservoir of nutrient-rich water.

Wicks, like you’d use for a candle, connect the reservoir to the plant roots and soak up the water, using capillary action to deliver the water to the plants’ roots.

The problem with the wick system is that it doesn’t allow for maximum oxygen intake, which is essential for fast, healthy growth.

One of the most popular systems is the ebb and flow method. This process is classified as an active recovery system because the nutrient solution is pumped to the plants, flooding the tray.

After a set amount of time, the water is then drained back into its reservoir to await the next flood.

This system is popular because it requires little maintenance and it’s highly effective.

Another type of hydroponic system is the continuous drip method, which is active and can be recovery or non-recovery.

Nutrients are dripped directly onto the growing medium. Any excess water may or may not be recaptured by an underneath tray to be redelivered to the reservoir.

The drip system works effectively because it’s easier to distribute different portions to different plants. It also makes it easy to use varying growing mediums. Both of which allow the farmer greater control over the growing process.

Hydroponic Materials:

While there are many different processes for growing plants using hydroponics systems, there are a few necessary materials that they all have in common.

The basic materials needed for a hydroponics system are growing mediums, nutrient solutions, and lighting.

The growing medium is used to support the plant and its roots. The medium can’t decay or break down quickly and needs to be able to hold moisture and oxygen well so that the plants need less frequent watering.

For ebb and flow systems, mediums that drain quickly are recommended for faster recycling.

Common growing mediums are hydrocorn, porous clay pebbles; rockwool, cubed stones; coconut fiber or chips; vermiculite, a natural mineral; and sand.

The nutrient solution is highly concentrated with essential vitamins and minerals. It usually comes in liquid or powdered form in order to easily mix it with water.

The solution is a substitute for soil, providing all the same nutrients in a more direct and potent way. As a result, plants grow stronger and faster.

Monitoring the pH levels of the solution is an essential part of the farming process. Like soil, pH levels must fit certain plant needs, otherwise crops can’t absorb all the nutrients they need.

Traditionally, plants also need plenty of sunlight.

During the process of photosynthesis, plants absorb energy from the sun to produce glucose out of carbon dioxide and water.

Outdoor hydroponic systems use sunlight as per usual. But indoor systems like container farms use powerful lights to feed crops.

Our Pure Greens container farms use 5500K White LED light bulbs for effective and energy efficient growing.

Hydroponic Process:

The first step in the process of crop cultivation is planning what seeds to sow.

Profitability is an overarching consideration when it comes to selecting crops. Profitability is dependent on affordability, potential yield, and maintenance.

Expensive seeds can result in products that fetch a high price, but it results in fewer plants.

The more expensive the seed the more you must sell your crop for in order to make a profit. If no one wants your produce, it’ll be hard to sell.

When planning your farm, keep in mind profit margins will vary depending on season, location, and demand.

Research how much certain crops sell for in your area. If a product is hard to find in the local market, the selling price will likely increase.

One benefit of indoor hydroponic systems is the ability to grow crops when they’re not in season, filling a hole left otherwise open by field farming.

Selecting plants with a high yield for little maintenance like microgreens offers the potential for greater profits.

Inexpensive crops with high yields, like romaine lettuce, also have high profit margins.  

Once you’ve decided on what to grow, it’s time to start sowing.

Start your plants with seeds rather than seedlings, which have already been germinated. Seedlings may be damaged, diseased, or infected with pests, threatening other plants in your farm.

Starting with seeds gives you greater control over your plant’s health.

Use grow cubes to plant seeds using a hydroponic system. Grow cubes are often made from similar materials as growing mediums, such as rockwool and coconut fiber.

Start by soaking your cube until its completely saturated.  

Place one to three seeds in the cube. Planting more than one seed at a time improves chances of at least one seed germinating per cube. It also gives you the option of preserving only the strongest plants.

The seeds will grow best in humid conditions. Place the cubes inside a humid enclosed container with about a half to a full inch of water on the bottom.

Remove the lid sporadically over the next week or so. Re-soak or mist any dry blocks.

When sprouts’ roots start poking through the grow cube, they’re ready for transplanting to the grow medium. After you’ve placed the sprouts in the medium, set them in the hydroponic system.

Pay close attention to crops as they grow. How you care for your plants will vary depending on species and the system you use.

While the risk for disease and pests is lowered for container farms, it isn’t eradicated. Watch for signs of unhealthy plants in order to minimize harm.

Track the growth of crops to have an estimate of harvest dates and to know whether to adjust the nutrient solution.

Once your crops are fully mature, harvest as normal.

For plants with fruits or berries, simply pull off the produce. For plants like lettuce that are harvested fully, pull the roots out of the grow medium.

Remove any roots and unhealthy leaves and wash thoroughly before packaging.

If you plan to sell your yields, there are several different ways to do so.

Set up a booth at a local farmers’ market to interact with customers directly. Research which ones have the highest attendance in your area.

Alternatively, ask local vendors if they’d be interested in selling your product for you. Be sure to bring fresh samples of your goods with you for a sales pitch they won’t be able to resist.

If you want to see your produce in action, approach local restaurants. Set up a meeting with chefs who are known for using locally produced vegetables and herbs.

If you have a high volume of produce, finding a wholesale distributor might be the way to go. Distributors will sell your products to vendors for you.

In this article, we learned about hydroponic systems and the process of growing crops using them.

With an understanding of the grow process in hand, what’s stopping you from getting started?

Visit our website or give us a call at 602-753-3469 to learn more about how you can start growing in your own high-tech Pure Greens container farm.