Hydroponics

There are three ways to face a crisis: panic, detachment, or engagement. Panic is entertaining. But it wastes and misdirects valuable energy. Detachment is easy. But it may leave us to neglect what we are responsible for. Engagement is when you face your problem directly, and analyze it for the right response. It takes humility to keep an open mind to new information and think through to the best response. It takes initiative, knowing that as an adult among just a bunch of other adults, you have to take responsibility to work for the best. And it takes grit. Because life isn’t comfortable.

As a consequence of the lockdown, we may go through an economic contraction. Many people were struggling before it began, and you cannot legislate wealth into existence. You have to work for it. When contractions happen, people have to refocus on the essentials. During the Great Depression, many people grew their own food. Those skills are not as common as they were then, so if we have to do that again we may face a steeper learning curve to get there. City dwellers have the additional challenge of finding a plot to grow their food. We may have a challenge ahead of us.

To plant a garden is to believe in tomorrow.
– Audrey Hepburn

Hydroponics is a method of gardening that uses water mixed with nutrients instead of soil. There are many advantages to this method, including:

-grow year round

-no soil required

-plants immune to soil-borne diseases

-no pesticides required

-grows more in a smaller space

-conserves up to 90% of the water

-simple or complex

-commercial kits or DIY

-inexpensive or expensive to set up

-inexpensive to maintain

-no weeding required

-plants grow 20% more quickly

-plants grow 25% larger

(1)(2)(3)(4)

Methods

Beginner

Wick

Design: plants sit in a grow medium. A wick connects the medium to a reservoir of a nutrient solution.

Medium options:

50:50 perlite: vermiculite

Wick:

Nylon

Pros:

Cheap

Durable

Low maintenance

No electricity required

Ideal for organic hydroponics

Small plants and herbs

Cons:

Not enough water for larger or water-hungry plants

Prone to algae if exposed to light

Deep Water Culture

Design: plants sit in a styrofoam raft floating on a nutrient solution and a bubbler air pump supplies the oxygen.

Medium options:

Volcanic lava chips

Expanded clay pellets

Net cups

Pros:

The cheapest

Reliable

Good for water-hungry plants

Cons:

Not for long lived or large plants

Requires electricity

Regular cleaning to prevent root rot

Frequent refilling

Ebb & Flow

Design: a water pump brings the nutrient solution to the grow bed which is flooded and drained using a timer to stop the pump or a bell siphon.

Medium options:

Rockwool

Volcanic lava chips

Perlite

Coconut coir

To find out how often to flood and drain the grow bed, read this article: https://www.leaffin.com/flood-drain-hydroponics-watering-schedule/

Pros:

Customize water schedule

Can separate plant water schedules

Efficient

Affordable

Customizable

Cons:

Requires electricity

Must keep running

Requires a lot of grow media

Harder to inspect the roots

Advanced

Drip System

Design: a water pump and timer bring the solution to the plants via drip irrigation.

Miedium options:

Expanded clay pellets (fast draining)

Pros:

Easy to remove individual plants

Tropical veggies are well suited

Cheap

Durable

Cons:

Prone to clogging

NFT System (Nutrient Film Technique)

Design: plant roots hang down into the air and touch a stream of nutrient solution that flows in a continuous loop. Note: if roots do not yet reach down, solution should be dripped from the top.

Pros:

Space efficient

Well oxygenated

Cons:

Continuous pumping crucial

Not for plants with heavy roots

Least common type

Prone to clogging

Aeroponic System

Design: roots misted with nutrient solution.

Pros:

Faster growth

Space efficient

Cons:

Volatile pH

Vulnerable roots

Requires high-quality fertilizer. Not organic.

Time consuming

Depends on sophisticated misters and pumps. Nozzles may fail.

(5)(6)

Types of Plants

Possibly any kind of vegetable or herb can be grown hydroponically, but some are more suited to the hydroponic system. Here is a list of some:

Herbs

Oregano

Cilantro

Mint

Tarragon

Peppermin

Basil

Sage

Stevia

Lemon balm

Rosemary

Ginger

Chives

Vegetables

Spinach

Swiss chard

Kale

Bok Choy

Tomatoes

Peppers

Strawberries

Cucumber

Celery

Beans

Radishes

(5)(7)(8)

Supplies

Growing Medium

This is a material used to hold up the plant, and supply oxygen, nutrients, and water. There are many different kinds of media. An excellent overview can be found at https://www.leaffin.com/growing-media-aquaponics-hydroponics/. (9)

Nutrients

This is basically what plants would be getting from the soil. They can be organic or chemical, but the organic is more likely to clog systems with water pumps or nozzles. Some gardeners supplement with the organic nutrients while primarily relying on the chemical kind to protect the pumps. There are liquid and powdered varieties. The liquids generally dissolve more easily and have a pH buffer, though they are a little more expensive. (10) Nutrient solutions can be replaced every two to three weeks. (16)

Pumps

Pumps used in hydroponics are usually your basic submersible pump. To find out what strength of pump you need, you need to calculate two things: the volume of water in your grow area the pump will be lifting, and how high it needs to lift it. Once you find the volume of water, multiply it by two. It is better to go for a pump with more power than you need than less. Then look for GPH or gallons per hour on the package.

It is important to calculate how high the water will be lifted. That is because the taller the column of water being raised, the more weight the pump has to lift. As the pump lifts the water higher, it’s ability to move the same amount of GPH decreases until it is gone. There should be an indicator showing levels of GPH at different heights.

Pumps can be disassembled and cleaned with soap and water when the nutrients are replaced. A filter if absent can be added on the inlet. DIY filters can be made from furnace or swamp cooler screens, or foam sponges. (11)

You can check out reviews for various pumps here.

If you are using a timer with your pump, look for a mechanical heavy duty (15 amp) timer with specific enough increments of time for your needs. (12)

A bell siphon is an alternative to a timer. It is made out of simple parts like PVC, so it does not require electricity. If you need a bell siphon for your ebb & flow system, this is an example of a DIY build, and this video goes into greater detail about how the dimensions effect the flow rate.

If your system requires an air pump, here are some reviews. You will also need tubing, which should be garden safe and dark to prevent algae, and an air stone. Smaller openings in the stone are better. Here are some tips to help quiet the air pump.

Lighting

Plants require at least 6 hours of sunlight per day. You may need to purchase supplemental lighting. This can be more expensive. If you are not buying a kit, you should look for HID (High-Intensity Discharge) lighting. This includes HPD (High-Pressure Sodium) bulbs which are better for vegetative growth. T5 lights are good for cuttings and plants with short life cycles. (5) For an in-depth look at lighting, you can read this article. Lighting should be put on timers to create an artificial day and night.

Environmental Tests

You will need meters to test water temperature, humidity, the mineral concentration in the water, and the pH level.

The temperature of the water should be between 59-86 degrees Fahrenheit (15-30 degrees Celsius). Higher temperatures reduce the amount of oxygen dissolved in the water and creates an environment more conducive to disease, but also increases the plant’s metabolism. Different plants do well in different temperatures. (13)

Humidity should be between 40-60%. Higher rates can lead to mildew and fungal problems. A humidifier or dehumidifier can be used to control levels.

High mineral content blocks nutrients from dissolving and can be filtered out.

PH should be between 5.8 and 6.2. Chemicals sold for this purpose can adjust the pH levels. Check pH weekly. (14)

Air circulation is important for CO2 levels, so a fan or intake-and-exhaust system should be used. (5)

Pests and Diseases

Algae are small plants that can grow where there is water and light. This is a common and serious problem for hydroponic systems. They can steal nutrients meant for your vegetables, deplete the water’s oxygen supply, mess with the pH, and attract gnats. To control algae, block the light from reaching the water. (6)(15) For more extensive methods to deal with an algae problem, you can read this article.

Inspect plants for signs of disease or infestation and separate it from the others if discovered. (1) Here and here are two articles that discuss what diseases or pests to look out for and how to prevent and deal with them.

Tutorials

For those who want to go the DIY route, alovegarden.com has an excellent article giving a list of 23 different tutorials to build your own hydroponic system, as well as the difficulty level.

How To Build A Simple DIY Hydroponics System – 23 Easy DIY Hydroponic Plans

Wikihow has three simple tutorials as well.

https://m.wikihow.com/Build-a-Homemade-Hydroponics-System

Resources

To learn more, you can browse this website with in-depth technical knowledge.

https://agradehydroponics.com/blogs/a-grade-news

This website contains several scientific articles on relevant topics to growers:

Blog

An excellent community resource can be found here:

https://www.reddit.com/r/hydro/

I hope when we see hard times on the horizon it does not force us to retreat into our snuggie fortresses armed with a gallon of ice cream, a Netflix subscription, and a battery of sarcastic memes to ward off the scaremongers. I hope we feel empowered. I hope we feel invigorated with the knowledge that we have the opportunity to solve important problems. I hope we feel a reignited bond with each other, that we are in this fight together. I hope we can look into a future in which we may walk into the kitchen and pluck off a crisp fresh breakfast from a system that gives us a continuous supply of almost free healthy food. And we will wonder why it should be any other way.