Project Guide

How-To: Plants and Rocks Container Gardening with Hydroponics


Difficulty: BeginnerTime: 4-6 Hours Print

Container gardening with hydroponics is an innovative way to grow plants using water, rocks and nutrient solutions – no soil required. Whether you’re short on space or looking for a low-maintenance option to cultivate fresh herbs, vegetables or ornamental plants, hydroponic gardening offers an efficient, sustainable solution. This step-by-step guide will walk you through creating your own hydroponic container garden using simple materials and techniques.

What Is Hydroponic Gardening?

Hydroponics is a method of growing plants without soil, using nutrient-rich water as the growing medium. In place of soil, a growing medium such as rocks or clay pellets provides root support while allowing water and nutrients to circulate. There are several types of hydroponic systems, each suited to different needs and levels of expertise:

  • Nutrient Film Technique (NFT): A shallow stream of nutrient solution flows continuously over plant roots; ideal for lightweight plants like herbs and lettuce.
  • Deep Water Culture (DWC): Plant roots are submerged in oxygenated water containing nutrients, making it great for fast-growing plants like leafy greens.
  • Drip Systems: Nutrient solution is dripped directly onto the roots at timed intervals, offering control over water usage and nutrients.
  • Wicking Systems: A passive system where a wick delivers nutrients and water from the reservoir to the plants; suitable for beginners.
  • Ebb and Flow (Flood and Drain): The growing medium is periodically flooded with nutrient solution and drained, providing plants with water and oxygen.

This guide focuses on a DWC system combined with a rock-based growing medium for easy setup and maintenance.

Tools

  • Small air pump and air stone

Materials

  • Growing medium
  • Clay pellets
  • Lava rocks
  • River rocks
  • Hydroponic nutrient solution
  • Net pots or mesh planters
  • Seeds or seedlings of your choice
  • Waterproof container or bucket

1. Choose Your Container

Select a container that fits your space and the plants you want to grow. Clear containers should be avoided as they allow light in, which can encourage algae growth.

2. Add the Growing Medium

Fill your container with your chosen rocks or pellets. These materials provide stability for the plants while allowing water and air to flow freely around the roots.

3. Prepare the Nutrient Solution

Mix the hydroponic nutrient solution according to the instructions on the package. Fill the container so that the solution reaches the bottom of the roots but doesn’t submerge the entire plant.

4. Set Up the Air Pump

If you’re using an air pump, attach the air stone and place it at the bottom of the container. This will oxygenate the water and keep the nutrient solution circulating. This step is crucial for a DWC system.

5. Plant Your Seeds or Seedlings

Place seeds or seedlings into the net pots, then position them in the rocks so the roots can access the nutrient solution. Make sure the plants are stable and not submerged.

6. Monitor and Maintain

Regularly check the water level and add nutrient solution as needed. Watch your plants for signs of growth or distress, such as yellowing leaves.


For those who prefer a ready-to-use solution, hydroponic systems and kits are available at your local Home Depot store or online, making it even easier to get started with this innovative gardening method. This Hydroponics Growing System Kit and Vertical Planter from Gardyn is also a great ready-to-go solution.

Benefits of Rocks in Hydroponics

Rocks in hydroponic systems provide excellent root support and allow for easy water drainage. Unlike soil, they are reusable, lightweight and resistant to pests, making them an ideal choice for home gardeners.

Best Plants for Hydroponic Container Gardens

  • Herbs: basil, mint and cilantro
  • Leafy greens: lettuce, spinach and kale
  • Small fruits: strawberries
  • Ornamental plants: Pothos, Philodendrons and succulents

Container gardening with hydroponics is a rewarding way to grow fresh, healthy plants in a small space. Combining rocks and nutrient-rich water can create a thriving garden that minimizes waste and maximizes efficiency.