The “wick system” – an inexpensive method of sub-irrigation
Posted on January 3, 2012 by Ed Ellis

For the past 12 years we have installed thousands of plants on the “wick system.”  This is an inexpensive method that establishes a water reservoir, below the plant. The plant obtains water from this reservoir through a cloth wick, in the amount it needs, eliminating the necessity for directly watering the plant.  This sub-irrigation system will allow you to water your plants every 2-6 weeks, depending on heat, light, ventilation and the type of plant.  A friend of mine who takes long vacations, will return after 4 weeks, to find their plants looking great!  With this system, plants take the amount of water they need, and the guess work is taken out of plant watering.

We like the wick system, because we can set up a plant on the system in seconds, and change a plant out in the same amount of time.  There are many sub-irrigation systems, by Jardinier, Lechuza and Planter Technology(and many others), which are much more expensive and involve directly planting the plant into the container.  We use these for certain situations, like the Jardinier system, is great for directly placing plants into the ground of an atrium.  The wick system would not do for that application.

To set up your plants on the “wick system”, you will need the following:   1.  a deep plastic saucer or liner(obtained from any plant shop, florist or Home Depot.  2.  a piece of wick, long enough to be placed by a screw driver into the center of the root ball, and to extend outside the grow pot about 3-4 inches(obtained from our company – I don’t see them offered anywhere).   3.  a spacer, to be placed into the saucer, and for the plant to rest on. Now the spacer could be anything that does not degrade in water.  A friend of mine uses styrofoam blocks.  I have used spray can tops(at home).  Our company goes to Home Depot, or Lowes and buys 4″ plastic drain pipe – white.  We cut it into 1″, 1.5″ or 2″ sections with a chop saw, and turn these on their side where these act as an excellent and cheap spacer.   Out of a 10′ pipe, for $5.00, you can get nearly 60  2″ spacers!

Now that you have your materials, place a number of spacers in the deep saucer, establishing a level and sturdy platform for your plant to rest on.  Make sure you cut your wick to the size, where at least 4″ is hanging out of the grow pot, and the other end is embedded (with a good sized screw driver), deep into the root ball of your plant.  This insures the water travels well into the root ball, and it will also trans-locate throughout the soil.  This is not heavy watering, but moisture with a decent amount of air remaining in the soil that prevents anaerobic bacteria and root rot from getting started.

Finally, place the plant on top of the spacers, within the saucer, and push the wick that is hanging out of the grow pot, to the bottom of the saucer.  By placing the wick on the bottom, your plant will eventually take up all the moisture in the saucer.  Now it is time to fill the reservoir.  Fill it to the bottom of the grow pot(top of the spacers), making sure the pouring in of the water does not displace the wick back up from the bottom.  Once the wick is wet, it will remain on the bottom.  As days go by, you will see the water level slowly lower, and then disappear.  We like to wait another week after the water is gone from the saucer, although if it is a water hungry plant such as a fern, spathiphyllum, or fishtail palm, don’t wait too long.

As you become more proficient at using the wick system for plant watering, you can try putting deeper spacers into the saucer, to extend the watering time for your plants.  I have three 6″ dracaena marginata – 5 plants per grow pot.  These are on 1.5″ spacers, in a deep 14″ saucer.  I water these every 5 weeks, and they look beautiful!  We use this system mainly on tropical plants, although I think it would work on succulents in good sunlight – they seem to use more water than you’d think.  Happy growing!



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