Semi-Hydro for Houseplants, the Easy Way!
Do you want to ditch and soil try growing houseplants hydroponically? That idea might sound intimidating, but this semi hydro growing technique makes growing remarkable plants so much easier. Let’s face it, soil is not simple. In fact all sorts of troubling questions exist when planting in soil including: Is the soil sterile? Am I watering it enough/too much? Will I get gnats? What’s my soil’s pH? Is my soil nutrient deficient? Can I just add tap water?
It’s time to try something new!
Most people relate hydroponic gardening to needing a lot of equipment, electricity, science know-how, and time, but that just isn’t true. A simple semi-hydro container, substrate, and nutrient water is all you need to keep your plant happy.
Semi-Hydro Container Essentials:
The term “semi-hydro” refers to a plants’ roots growing in a substrate rather than fully submerged in water. In a semi-hydro set up, an inner pot is filled with a substrate and suspended over a nutrient water reservoir in such a way so the water can be absorbed into the substrate. This can be done by contact directly with the bottom layer/s of substrate, or by using a wick. Here are a few things to consider.
- Clear outer pots can lead to algae growth, opaque container suggested
- Clear inner pots provide great visibility to easily monitor root health
- Have visible water line for easy maintenance
- The outer and inner pots must fit securely, the inner pot should not be fully submerged
- Airflow into the substrate will help ensure healthy dissolved oxygen levels
Choosing a Substrate:
In a semi-hydro set up, the substrate performs 3 key functions.
- First, providing the plant something to anchor onto. The roots will grow into the substrate and will be able to support all of the future foliage growth.
- Second, providing a large surface area between the nutrient water and air. This ensures a healthy supply of dissolved oxygen to the plant roots. If you have ever killed a houseplant because of overwatering it was because the roots did not have enough oxygen.
- Third, is providing a consistent supply of nutrient water to the plants roots.
There are dozens of different substrates and mixes available to try, but two that specifically work great for Aroid houseplants are 8mm LECA, and Pon.
LECA - The shorthand version of “Lightweight expanded clay Aggregate” is just clay that has been heated to very high temperatures (1200 C). The high temperature causes thousands of tiny bubbles to expand and form a very porous structure. This substrate is lower in cost and readily available at your local hydroponics store. The 8mm size provides extremely good airflow to all of the roots and offers good root visibility compared to other substrates.
“DIY” PON - Is the more luxurious houseplant substrate. While Leca has been compared to “looking like dog food kibble” by some of the cruelest online critics, Pon has a very beautiful speckled pattern with vibrant colors. It is a mixture of several different components often used as soil additives including perlite, seramis, zeolite, pumice, activated charcoal, lava rock, etc. and the “recipe” seems to vary depending on who you ask. My 3 favorite are:
The common traits between all of these mixture options include: a rigid/pores structure, inert/sterile compound, and transports/holds water for the plant roots. “DIY” Pon will be a denser mixture compared to 8mm Leca. This will provide a little more weight for anchoring the plant, and less voids which is better for plants with less developed roots.
Mixing Nutrient Water:
Plants cannot survive on water alone, and require at least three essential nutrients (Nitrogen, Phosphorus, and Potassium) to survive. Growing hydroponically gives you full control of what nutrients you feed your plants, and in what ratios. Below are links to two different recipes.
Keeping it easy:
This recipe works great for a wide variety of houseplants and only requires tap water, one nutrient product, and a dropper that measure in the range of 1-5 mL.
Take it to the next level:
This recipe is for the more serious growers that want maximum results and don’t mind a few extra steps.
www.Variegatedplants.shop has assembled Inna’s Planter Kit 2.0 to include everything you need to get started with Semi-Hydro in one box. It comes in a single pack or a twin pack with your choice of LECA or Inna’s mix (Seramis, Zeolite, and Lava Rock).
- 4” Inner and outer cache pot (with cotton wick)
- LECA or Inna’s Mix
- Key Grow’s Blue Butterfly Nutrients, 8oz
- 1mL-5mL dropper
- Getting Started Guide