There’s no need to wait for springtime to start a garden. And you don’t even need to have a yard. With some water, some light and some basics, you can grow plants hydroponically.
Hydroponics is a method of growing plants using a mineral solution dissolved in water instead of soil.
Here’s how to get started.
Why grow hydroponically?
There are lots of reasons that someone might want to try growing vegetables and herbs hydroponically, said Dutch Baggerly, a manager at Long Beach Hydroponics and Organics.
One reason is lack of adequate garden space: Some people don’t have a big backyard, or their backyard is mostly concrete, or maybe they have clay dirt that’s hard to grow things in. Having a hydroponic system lets them sidestep those challenges.
Hydroponic gardening also allows gardeners to control all variables in a way that they can’t with traditional soil growing, such as PH, strength of the solution that plants grow in. Taking care of the plants becomes a science.
“You aren’t just setting the stuff out, digging a hole and saying, ‘Oh I hope it grows,’ you actually have control over how well it grows, how fast it grows, all different aspects to where now you’re in the driver’s seat and you’re controlling your garden 100%,” Baggerly said.
Interest in hydroponic gardening is picking up, he said, and once people actually start to do it, they realize how fun it can be.
“Their creativity level kind of boosts because they’re seeing all these different things that they can control in their garden.”
What kind of plants should you grow hydroponically?
“Just because you can grow something in a hydroponic system, doesn’t mean you should,” said Eileen Cullen, a professor of plant sciences at Cal Poly Pomona’s Don B. Huntley College of Agriculture.
She said that the kinds of plants that do well hydroponically are usually leafy greens such as lettuce, spinach, kale, mustard greens, bok choy and swiss chard and herbs such as basil.
You can also grow some fruiting plants hydroponically, including cherry tomatoes, cucumbers and even strawberries.
At AGRIscapes, the outreach and education center for Cal Poly Pomona, they’ve been growing strawberries hydroponically for years.
Craig Walters, director of AGRIscapes, said that the land that AGRIscapes uses has heavy clay soil and the climate is a little hotter than strawberries tend to prefer so a professor came up with the idea to start growing them hydroponically.
Now they’re grown inside stacked styrofoam containers and and a system pumps in a fertilized water solution as needed.
Cullen recommended some crops to avoid growing hydroponically.
Plants that have such deep root systems that will drink up the nutrient solution too quickly or just won’t grow well include potatoes, sweet potatoes, corn, hops, turnips, onions, garlic, pole beans and peas, Cullen said.
Types of hydroponic systems
Cullen said there’s a lot to consider before delving into hydroponics. Before heading to the store, a potential grower will need to think about what kind of system they want, where they want to put it and what kind of light they need.
There are two types of systems, Cullen said: dynamic or active systems, which use pumps that oxygenate the water, and static or passive systems which do not.
An example of an easy active system would be a deep water culture system. With this system plants sit on a platform that floats on a nutrient solution. Their roots grow in the nutrient solution and an air pump connected to an air stone bubbles the solution, providing oxygen.
Rudimentary versions of this system can be purchased from $50 to $300 (though some more advanced versions could be as expensive as $700).
A passive system would be something like the Kratky method, where plants are in a non-soil growing material such as rock wool and their roots sit in a nutrient solution. Part of the developed root system sits above the nutrient solution, which is how the plant gets its oxygen in this method. The plants and solution can sometimes be placed in something as small as a mason jar. You can get the supplies for this method starting around $20-$30.
Cullen said you can sometimes find the mixture for the nutrient solution already prepared at some stores.
Where you place your system can determine how much light you need. Systems placed indoors may need supplemental lighting. Cullen recommends talking to your local hydroponics store to determine what your light setup should look like.
Care considerations
So you’ve planted your leafy greens, tomatoes or cucumbers in your hydroponic system. What next?
“The plants will tell you a lot,” Walters said. “If the leaves start turning yellow or wilting you’ll know a lot from that.”
Yellow leaves can be a sign of nutrient deficiency.
Walters said it’s important to pay careful attention to directions to make sure that the solution that the plants are growing in has the right amount of nutrients for the plant.
“If you overfertilize that can be as bad as not fertilizing at all,” he said.
You want to keep the area around the plants clean and dry and dispose of plant waste like dead leaves in order to prevent exposing the plants to potentially harmful pathogens, Cullen said.
But if you follow those directions you’ll soon have fully grown leafy greens or cherry tomatoes that you grew with scientific precision.
“You have total control over what you put into that head of lettuce, and I think for a lot of people it gives them peace of mind,” Walters said.