Keeping Clones in Clay Pellets

by Bob
(Fish and Jacks, Canada)

I was wondering, what is the best way of keeping clones under fluros. I have built a hydro set up like the one in "My Most Successful Homemade Hydroponics System". I will be transferring the the clones into the hydro tubes in about 4 weeks due to the fact that I have some plants on 12/12 light schedule at the moment.

I was going to use the 16 ounce cups and clay balls for the clones, just not sure what is the best way to grow the clones until they find their home in the hydro tubes.

Much appreciated, Bob

Answer: Bob- before you put your clones in clay pellets, be sure they have roots. If they do not have roots, I suggest leaving them in your cloner for the moment....I have never had any success getting fresh clones to root in expanded clay pellets/balls. If your clones have some roots already, I have a few suggestions for you.

First, your fluorescent lights should be placed just a few inches above your clones....the strength of the light decreases very rapidly with distance from the bulb (and fluorescent light isn't that strong to begin with). Fluorescent lights will only support good growth within 12 to 15 inches from the light. If you are starting with 6 inch clones, you should be fine. Also, it is better to use two fluorescent lights than to try crowding all of the plants under one light.

When clay pellets are used in a hydroponic system, they need to be soaked for about 20 minutes each cycle to really absorb the correct amount of moisture. You may have noticed, most of the systems you see them in are flood and drain (ebb n flow) or deep water culture (DWC) systems.

The system you have built is a cross between a nutrient film technique (NFT) and a DWC. Because the cups full of clay pellets will be sitting in a certain amount of water constantly, the whole "water absorption" thing is not really an issue. However, when trying to come up with a temporary home for the clones, it may be.

Your best solution to this problem would be to duplicate the environment the plant will end up in as best as possible. I suggest getting a plastic container about 5 inches high and big enough to hold all of your clones/cups. Fill the container with 2 1/2 to 3 inches of nutrient solution.

The fluorescent lights aren't that bright, so the nutrient solution doesn't need to be that strong (50% strength should work well, or 700 ppm if you have a TDS meter). Be sure to use an air pump/air stone in the reservoir to add plenty of oxygen to the nutrient solution....nutrient absorption only occurs in the presence of oxygen, and you don't want your little guys starving!

On the page My Most Successful Homemade Hydroponic System, follow the directions I give for transplanting your clones into the cups....especially the part about using PRE-SOAKED clay pellets (you will have a much better success rate). You don't want to plant the clone too deep or too high up in the cup. Just follow the directions in the page above and you should be fine.

Finally, it is a very good idea to place an oscillating fan on the clones a few feet away. The plants don't have lungs, so when they exhale oxygen from their leaves, it tends to hang in the air around the leaf and choke out the plant a little bit. The oscillating fan not only helps the plants exchange oxygen for CO2 from the air, but also forces the little clones to grow thicker stems. This will help the clones support themselves, and will help them support any produce they grow later on. Happy Growing!