If you’ve ever placed a plant cutting in a jar of water to grow roots, you’ve already practiced the basics of a popular growing technique. So, what is it called when you grow a plant in water? The formal term is hydroponics, but many people simply call it water gardening or hydroculture.
It’s a clean and fascinating way to have greenery indoors. You don’t need soil at all. The plant gets its nutrients directly from a specially prepared water solution. This method lets you see the root systems develop, which is part of the fun.
Hydroponic Gardening Method
While growing a single cutting in water is simple, the full Hydroponic Gardening Method is a broader system. It supports plants through their entire life cycle without soil. The roots are anchored in an inert material like clay pellets or rockwool. Then, a nutrient-rich water solution is delivered directly to them.
This approach is efficient and controlled. It’s used for everything from home lettuce kits to large commercial greenhouses. The core idea is always the same: feed the plant, not the soil.
Why Try Growing Plants in Water?
There are some clear benefits to water-based gardening that make it worth a try.
- Less Mess: Forget about dirt under your fingernails or spilled potting soil on the floor. It’s a much cleaner process from start to finish.
- Fewer Pests: Many common insects, like fungus gnats, live and breed in soil. Removing soil from the equation eliminates a whole host of pest problems.
- Water Efficiency: Hydroponic systems use significantly less water than traditional gardening. The water is recirculated in a closed system, reducing waste through runoff or evaporation.
- Faster Growth: Plants often grow quicker. Because nutrients are immediately available, the roots don’t have to search for food. The plant can put more energy into growing leaves and fruit.
What You Need to Get Started
You don’t need complex equipment to begin. Here’s a basic list of supplies for simple water growing.
- A Vessel: A glass jar, vase, or specialized propagation station. Clear glass lets you watch root growth.
- Water: Use tap water that has been left out for 24 hours to let chlorine evaporate, or use filtered water.
- Nutrients: For long-term growth, you’ll need hydroponic fertilizer. Plants in plain water will eventually run out of food.
- Support: For cuttings, the mouth of the jar can support the stem. For larger setups, you may need a net cup or a piece of foam to hold the plant.
- Plants or Cuttings: Choose plants known to thrive in water.
Best Plants for Water Growth
Not every plant is suited for a life in water. Some are champions at it. Herbs and leafy greens are particularly adaptable.
- Herbs: Mint, basil, oregano, and sage root easily in water. You can keep a fresh supply on your windowsill.
- Leafy Greens: Lettuce, kale, and spinach perform very well in hydroponic systems.
- Houseplants: Pothos, philodendron, spider plant, and lucky bamboo are classic choices. Many can live in water for years with proper care.
- Vegetables: Tomatoes, peppers, and cucumbers can be grown hydroponically, but they usually require more support and light.
A Simple Step-by-Step Guide
Let’s walk through the process of starting a plant cutting in water. It’s the perfect weekend project.
- Take a Cutting: Choose a healthy stem from a parent plant. Use a clean knife or scissors to make a cut just below a leaf node (the bump where leaves grow). A length of 4-6 inches is good.
- Prepare the Cutting: Remove any leaves that would be submerged in the water. This prevents rot. You can leave a few leaves at the top for photosynthesis.
- Place in Water: Fill your jar with water and place the cutting inside. Ensure at least one or two nodes are underwater, as this is where roots will emerge from.
- Find the Right Spot: Put the jar in a location with bright, indirect light. Avoid direct, hot sun which can overheat the water and encourage algae.
- Monitor and Maintain: Change the water every week to keep it fresh and oxygenated. Once roots are a few inches long, you can add a dilute hydroponic nutrient solution every month or so.
Common Problems and Solutions
Even this simple method can have hiccups. Here’s how to troubleshoot.
- Algae Growth: Green slime in the jar means too much light is reaching the water. Switch to an opaque container or wrap the jar in foil to block light from the roots.
- Root Rot: If roots turn brown and mushy, they are decaying. This is often due to lack of oxygen. Change the water more frequently and ensure the cutting isn’t sitting in stagnant water for to long.
- Slow Growth: If roots are taking forever to appear, be patient. Some plants are slower than others. You can try a rooting hormone on the cut end before placing it in water.
- Nutrient Deficiency: Yellowing leaves on an established water plant usually signals hunger. It’s time to start adding a gentle fertilizer to the water.
Scaling Up to a Hydroponic System
If you enjoy growing cuttings, you might consider a small active hydroponic system. These use pumps to circulate the nutrient solution, providing even more oxygen to the roots. Popular beginner systems include:
- Deep Water Culture (DWC): The plant’s roots dangle directly into an aerated nutrient solution. An air pump and stone add vital oxygen.
- Kratky Method: A passive, pump-free system. The plant sits in a net pot, and its roots grow down into a reservoir of nutrient solution. As the water level drops, air roots develop.
- Nutrient Film Technique (NFT): A shallow stream of nutrient solution constantly flows over the roots, which are supported in a sloped channel.
Each system has it’s own advantages, but DWC or Kratky are great for first-timers.
FAQ About Growing in Water
Can any plant be grown in water?
No, not all plants can adapt. Many plants, especially those that form taproots or need very dry conditions, will simply rot. It’s best to start with plants known for their adaptability to hydroculture.
Do I need special fertilizer?
Yes, you should use a fertilizer formulated for hydroponics. Regular garden fertilizer is designed to feed soil microbes first and may not have the right balance of nutrients in an accessible form for water roots.
How often do I change the water?
For simple jars, change the water completely every 7-10 days. In active recirculating systems, you top off the reservoir with fresh water and change the entire nutrient solution every 2-3 weeks.
Is it cheaper than soil gardening?
The initial setup for a hydroponic system can be more expensive. However, over time, savings on water, fertilizer efficiency, and higher yields can balance the cost. Growing cuttings in jars is very low-cost.
Why are my plant’s leaves turning yellow?
Yellow leaves are a common sign of nutrient deficiency, usually nitrogen. It can also mean the roots aren’t getting enough oxygen or the plant is getting to much light. Check your water quality and nutrient levels first.
Growing plants in water is a rewarding hobby that demystifies how plants eat and grow. It connects you to the basic biology of your plants in a visible way. Whether you keep a single pothos in a decorative bottle or set up a countertop herb garden, the Hydroponic Gardening Method offers a unique and efficient path to fresh greens and beautiful plants all year round.