It’s about time for an FAQ.

Instead of trying to finalize this page, I will add questions with answers when time permits.

1. Is this a new method of growing houseplants?
2. Over-watering is the number one cause of death for houseplants. If this is the case how can hydroculture plants survive since they are growing in water?
3. What kind of fertilizer can I use for hydroculture plants?
4. Are clay pellets widely available?
5. Are there mosquito problems because of the water?
6. What types of plants can be grown in hydroculture?
7. Is hydroculture the same as hydroponics?
8. How can the plant get watered without soil?
9. Is hydroculture similar to self-watering pots?
10. Don’t the roots eventually rot?
11. How can roots breathe in water without oxygen?
12. How can plants possibly grow without soil?
13. I cannot find the clay pellets locally and need to order online? Is there a place you can recommend?
14. Do I need to sterilize the pellets?
15. What method(s) can I use to sterilize the pellets?
16. If you are using a single container with no drainage holes, how can you rinse the medium?
17. What nutrients do you use and is it a continuous feeding?
18. How much water is added in each container?
19. Can plants be started from seed for the hydroculture growing style? If so, how?
20. Do you have to clean the clay pellets and water out of the containers periodically?

1. Is this a new method of growing houseplants?
   
   No. Hydroculture has been around for decades. It emerged from Europe where it is much more recognized. In offices and public spaces in Holland, Switzerland & Germany, 1/3 – 1/2 of all indoor houseplants are grown without soil.
   
   
   
2. Over-watering is the number one cause of death for houseplants. If this is the case how can hydroculture plants survive since they are growing in water?
   
   The answer is already in the question: ‘growing plants in water’. In hydroculture houseplants are grown with water, not in water. Since the roots of the plant are not submerged in the water, the plant cannot die from over-watering.
   
   
   
3. What kind of fertilizer can I use for hydroculture plants?
   
   There are hydroponic fertilizers available that provide plants with an appropriate balance of necessary nutrients, readily available at hydroponics shops if you have any near you.

   I have also been using the commercial houseplant fertilizer Miracle Gro regularly with satisfactory results. I dilute it to 1/10th the strength. Miracle Gro advises that I add 10 – 20 drops per liter, I add 1 or 2.
   
   
   

4. Are clay pellets widely available?
   
   Unfortunately, they are not always available locally. If you do not have a hydroponics shop in your area, you may need to shop for this product online.
   
   
   
5. Are there mosquito problems because of the water?
   
   Mosquitoes lay their eggs on the surface of fresh or stagnant water but in hydroculture there is no 'surface' of water. The water level is about an inch at the bottom of the container and the rest of the glass is filled with pellets. The 'surface' is clay pellets, not water. No fear of mosquitoes!
   
   
   
6. What types of plants can be grown in hydroculture?
   
   In my own opinion just about every plant is suitable for hydroculture – cacti and succulents included.

   For some suggestions, please visit: The Plants
   
   
   

7. Is hydroculture the same as hydroponics?
   
   Hydroponics is the high-end application, a method that’s automated, mostly related to the production of food. This method has been extensively used throughout Japan, the Middle East and Europe because of efficiency of water, space and a high yielding of results.

   Hydroculture is the low-end of growing plants in water. It is also referred to as passive hydroponic system, which means that it lacks all the automation commonly associated with hydroponics.

   The two methods are indeed related, sharing the same ideology – no soil – but functioning quite differently.
   
   
   

8. How can the plant get watered without soil?
   
   Although most people are used to watering from the top, it’s not necessary or the only way. Clay pellets - the growing medium of choice in hydroculture - retain moisture and transfer it to the roots of your plants by capillary action.
   
   
   
9. Is hydroculture similar to self-watering pots?
   
   Although they share some similarities – both systems ease the task of providing the plant with the appropriate amount of water – there are significant differences. Hydroculture does not include soil, at all. It has gone one step further and replaced the soil with a more sterile medium (expanded clay, known as hydroton). With self-watering pots, there is always the possibility of over-watering since soil is part of the equation; in hydroculture that possibility does not exist.
   
   
   
10. Don’t the roots eventually rot?
    
    How can they possibly rot? They never sit in water and you cannot over-water in hydroculture.
    
    
    
11. How can roots breathe in water without oxygen?
    
    As mentioned before, roots are never submerged in water when growing plants in hydroculture. However, water has oxygen in it, so even if your plants were soaking in it, as long as you changed it regularly, the oxygen would be replenished. The only way that the roots will die is if you submerge them in water and never change it.
    
    
    
12. How can plants possibly grow without soil?
    
    Your houseplants do not need soil to grow or thrive. It is not one of the requirements for optimal health. Plants need air, water, nutrients and sunlight, which are all provided in the hydroculture system. Soil anchors the plant, so do clay pellets.
    
    
    
13. I cannot find the clay pellets locally and need to order online? Is there a place you can recommend?
    
    There aren't any specific ones I can recommend, but you'll find a few listed on my links page that I’ve researched or dealt with.
    
    
    
14. Do I need to sterilize the pellets?
    
    Not always. I don’t sterilize my clay pellets unless there’s a good reason, such as a plant having been recently bug infested, or if I’m using the clay pellets to pot up another plant and want to be extra cautious.
    
    
    
15. What method(s) can I use to sterilize the pellets?
    
    a) Boil them. Yes, you heard right. Place them in a pot on the stovetop, cover them with water and boil them for 5 – 10 minutes. It’s quick and effective.

    b) Fill a container with 1 part bleach to 10 parts water and soak the pellets for a few minutes, then rinse thoroughly.
    
    
    

16. If you are using a single container with no drainage holes, how can you rinse the medium?
    
    Unfortunately, you have to completely disassemble the setup every now and then to thoroughly clean it, thus the added effort of a single pot. If you do not have time for this or don’t want to carry out this added maintenance step, grow your hydroculture plants in the standard double containers or in a single pot with drainage holes that is placed on a saucer used as a water reservoir.

    Visit the website: Houseplant Hydroculture and click on ‘Containers’ on the menu for information about the ‘Pot and Saucer’ method.
    
    
    

17. What nutrients do you use and is it a continuous feeding?
    
    I quite often use a hydroponic fertilizer that I pick up at the local garden center, diluted to 1/2 to 1/3 strength. Occasionally, I also apply liquid Miracle Gro that I dilute to 1/10th the recommended mix on the label. With these two products, I feed my plants the same way I did when they were in soil – occasionally and only if they are actively growing. Every 2 – 4 weeks for the really fast growers, once a month for the moderate ones and a couple of times a year for the very slow growers. In addition, I also use a slow release nutrient - loose granules that are sprinkled on top of the clay pebbles - added every 4 - 6 months; this is a continuous feeding process. Visit a local hydroponics shop for quality products or order online.

    For more info:
    Fertilizing Houseplants
    Where’s The Beef?
    
    
    

18. How much water is added in each container?
    
    There is no fixed amount of water in containers. I add anywhere from 1/2" to 1½”, sometimes just a little more – but usually below 2”. It all depends on the height of the container and how low the roots are situated. Just keep the water level below the roots.

    If you are uncomfortable with clear glass containers and the single pot method, consider using the standard double-pot method used in hydroculture that comes equipped with a water level indicator. Visit Houseplant Hydroculture to learn how to make your own water level indicator if you can’t find anything locally.
    
    
    

19. Can plants be started from seed for the hydroculture growing style? If so, how?
    
    Yes they can. Here are a couple of methods you can choose from:

    a) Throw seeds into a small, clear plastic bag and spray mist (inside the bag) to add moisture. Seal the bag and keep it in bright light (no sun) until roots form. Check regularly to make sure there is moisture in the bag and spray mist when necessary. When the seeds sprout and the seedling and roots have grown to a size that you can handle without breaking them, place the small plants in a cup of water, let them grow a little more and then pot them up in hydroculture. Or I place the seedlings in a tiny glass container with pellets and introduce them to hydroculture from the get go. Both ways work well.

    b) Purchase a seed starting tray (or use a small plastic container with a clear cover; an ice cube tray or a clear egg carton work well), fill the compartments with cotton balls, place the seeds on top and spray mist seeds and cotton; cover to keep humidity high. Place the tray in bright light (no sun) and wait for the seeds to sprout. Mist regularly to keep the cotton balls moist. When the seeds have sprouted, allow the seedlings to grow until their height reaches the cover, and then treat them as above. Place them in a cup of water to grow more or just transplant them straight into hydroculture.
    
    
    

20. Do you have to clean the clay pellets and water out of the containers periodically?
    
    Yes. I rinse the pellets and clean the containers every month, but you don’t need to go to that extent. Once every 3 – 4 months will suffice. Single pot (glass/plastic) containers are terrific but they require a little added effort. If you place them in the sun after you've fed your plants, algae can occur, at which point you'd have to disassemble the setup to clean it out. As an alternative, you can place that clear container inside a dark pot; or you can use darker glass; or you can use the double-pot method; or, or, or...

    There are so many ways to go. Glass containers are not the standard for Hydroculture, just my own preference. You don’t need to follow that style; you can create your own!

    Here is a link that offers a few ideas to help you get started:
    Put On Your Hydro Thinking Cap