DIY Flood and Drain System – Growing Lavender Indoors

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DIY Flood and Drain System - Growing Lavender Indoors

DIY Flood and Drain System – Growing Lavender Indoors

So here is my DIY Flood and Drain System inside a 2×4 grow tent where I’m growing lavender indoors. I go over its simple setup and it is fully automated.

DIY Flood and Drain System Video

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DIY Flood and Drain System: The Ultimate Guide for Growing Lavender Indoors

Discover how to master indoor gardening with our guide on the DIY Flood and Drain System! Learn to grow lavender and more in your own space.

DIY Flood and Drain System Key Takeaways:

  • DIY Flood and Drain System is an indoor gardening method where plants are periodically flooded with nutrient-rich water that then drains back into a reservoir.
  • This system ensures optimal moisture and oxygen for root growth, making it perfect for growing lavender and other plants indoors efficiently.

Growing Lavender Indoors

Indoor gardening enthusiasts, get ready to elevate your green thumb skills! In this post, we’re diving into the world of DIY Flood and Drain Systems, specifically tailored for growing lavender indoors.

I’ll walk you through my journey of setting up a 2×4 grow tent, highlighting its simplicity and full automation.

This guide is perfect for those looking to efficiently grow lavender or many other crops at home while exploring the wonders of indoor gardening systems.

What Is Lavender?

Lavandula (common name lavender) is a genus of 47 known species of flowering plants in the mint family, Lamiaceae. It is native to the Old World and is found in Cape Verde and the Canary Islands, and from Europe across to northern and eastern Africa, the Mediterranean, southwest Asia to India.

Many members of the genus are cultivated extensively in temperate climates as ornamental plants for garden and landscape use, for use as culinary herbs, and also commercially for the extraction of essential oils. Lavender is used in traditional medicine and as an ingredient in cosmetics. Wikipedia 

Understanding the Flood and Drain System

The Basics of Flood and Drain

A flood and drain system is an ingenious approach to plant irrigation. It alternates between flooding the root zone with nutrient-rich water and allowing it to drain back.

This method ensures optimal moisture and air circulation around the roots, crucial for healthy plant growth.

Components of the System

Key components of this system include a reservoir to hold the nutrient solution, a pump to circulate water, and trays for plant placement.

A unique addition is the ‘waffle grid’ which supports the pots above the water, allowing for efficient drainage.

Setting Up the Grow Tent

Assembling Your Tent

Setting up your grow tent is the first step. Choose a location that can accommodate the 2×4 tent size and assemble it following manufacturer instructions. Ensure it’s secure and stable before adding any plants or equipment.

Organizing the Space

Inside, position your reservoir and trays. Use a sturdy tote from a store like Home Depot for the reservoir.

Ensure there’s enough space for air movement and easy access for maintenance.

Grow Tent Ventilation: Ensuring Healthy Air for Your Plants

AC Infinity CLOUDLINE PRO S4, Quiet 4” Inline Duct Fan with 10-Speed Controller, EC-Motor Ventilation Exhaust Fan for Heating Cooling Booster, Grow Tents, Hydroponics
AC Infinity CLOUDLINE PRO S4, Quiet 4” Inline Duct Fan with 10-Speed Controller

Introduction to Ventilation in Grow Tents

In the world of indoor gardening, proper ventilation in your grow tent is as crucial as sunlight and water for your plants.

It’s not just about keeping the air fresh; it’s about creating an environment where your DIY Flood and Drain System and your plants can thrive. Let’s explore why ventilation is key and how to set it up effectively.

Importance of Proper Air Circulation

Proper ventilation in a grow tent does wonders. It regulates temperature, reduces the risk of pests and diseases, and ensures a steady supply of CO2 for photosynthesis.

Good airflow mimics the natural breezes of the outdoors, which is essential for strengthening plant stems and encouraging robust growth.

Setting Up Your Ventilation System

Setting up an efficient ventilation system involves a few key components:

  • Exhaust Fan: Choose a fan that’s appropriate for your tent size. It should be powerful enough to replace the tent’s air volume at least every few minutes.
  • Intake Holes: Ensure your tent has intake holes that are smaller than the exhaust fan. This helps maintain negative pressure, preventing odor leakage and ensuring fresh air is drawn in effectively.
  • Air Filters: Carbon filters are invaluable for eliminating odors, especially important if you’re growing aromatic plants like cannabis.
  • Oscillating Fans: These help circulate air within the tent, preventing hot or cold spots and ensuring each plant gets its fair share of fresh air.

Monitoring and Adjusting

Regularly monitor the temperature and humidity inside your tent. Adjust the fan speeds and opening of intake holes accordingly.

In cooler months, you might need to reduce ventilation to maintain warmth. In contrast, during hot spells, increasing airflow can help keep temperatures down.


Incorporating proper ventilation into your grow tent is a game-changer for your DIY Flood and Drain System.

It not only helps in maintaining an ideal growing environment but also ensures your indoor garden is healthy, vibrant, and productive. Remember, a well-ventilated tent is a happy tent for your plants!

Planting and Growing Lavender

Potting Your Lavender

Lavender can be slow to germinate but stratifying the seeds can help. It is also a slow-growing plant and new seedlings are tiny.

The plants in the video are about 4 months old from seeding.

Read my post: How To Grow Lavender in Pots:13 Easy Care Tips And Tricks – Rapid Daily

Start with small pots and gradually move to larger ones as your lavender grows.

This gradual transition helps the roots develop without stress. Use high-quality potting soil and ensure each pot has adequate drainage.

I use coco coir because it is a light medium and offers great drainage and water-holding capacity.

Choosing the Right Pots

You can consider using Root Maker pots They encourage air pruning of the roots, preventing root circling and promoting healthier plant growth.

This is especially beneficial for lavender, which thrives on well-aerated soil.

But any pot with drainage holes will work.  Just keep in mind lavender is a deep rooting plant so don’t use shallow pots for it. 

Lighting and Climate Control

Selecting the Right Lights

Lighting is crucial in indoor gardening. While COB (Chip On Board) lights were once popular, LED lights are now preferred for their efficiency. They provide a broad spectrum of light, ideal for plant growth.

Managing Temperature and Humidity

Maintain a consistent temperature of around 70-75°F and a humidity level of 50-60%. These conditions mimic lavender’s natural Mediterranean environment, promoting healthy growth.

Watering and Nutrient Management

Watering Schedule

Lavender doesn’t require excessive water. Set your flood and drain system to water once daily for about 3 minutes.

This ensures the roots receive adequate moisture without becoming waterlogged.

Nutrient Solutions

Use a balanced nutrient solution suitable for lavender. The flood and drain system will evenly distribute these nutrients, providing your plants with everything they need to flourish.

Lavender is not a heavy feeder so go easy on the fertilizer, especially for young plants. I am using Jack’s 3 2 1 formula but any good hydroponic nutrients will work. I keep my ppm at about 750.

Additional Plants in the System

volunteer cantaloup plant

Growing Companions

The lettuce plants and cantaloup plant were volunteers and the lettuce won’t be a problem but the cantaloup might need too much space.

Cantaloupe and lettuce are being grown alongside lavender. However, monitor their growth as they have different water and light needs. Adjust your system accordingly to accommodate these variations.

Managing Volunteer Plants

Volunteer plants like lettuce can sprout unexpectedly. Decide whether to integrate them into your system or remove them to maintain focus on your lavender.

If I keep the cantaloup I will try to limit its spread and train it to a trellis.

Adaptability of the Flood and Drain System

System Versatility

This system is adaptable to various plants. Adjust the size and number in your tray based on what you’re growing. For larger plants, ensure your system has enough space and support.

Choosing the Right Tray

Select a tray that fits your tent and accommodates your plants comfortably.

The tray size will influence how many plants you can grow and their overall health.

If you are using a larger grow tent or have more space larger flood trays are available.

Tips for Maximizing Grow Tent Efficiency

Space Utilization

In a compact space, efficient use of area is key. Arrange your plants and equipment to maximize light exposure and ease of access for maintenance.

Light Management

Adjust the light intensity based on plant growth stages. Younger plants require less intense light, while flowering plants may need more.


Creating a DIY Flood and Drain System for indoor gardening can be a rewarding project.

It offers a controlled environment for plants like lavender, providing them with ideal growing conditions.

Whether you’re a novice or an experienced gardener, this system is a great addition to your indoor gardening toolkit.

Happy gardening and remember to keep it green!

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