How Much?

How much water should I give my houseplant?  Simple.  You water until it comes out of the bottom of the pot.  We often get asked to quantify the amount that is needed.  Does it need to be a cup (8 oz.), a few tablespoons, or a gallon?  Every container is different in size and the volume of soil that it holds.  However, you need to water until you reach the bottom of the roots.

When we only provide a small amount of water in a container it is unable to move through the soil column and doesn’t reach all the roots.  Shallow watering may prevent potential water damage to the carpet or hardwood floors but does nothing for the health of the plant.

Furthermore, the container must have a drain hole.  Many decorative containers are now coming with no holes.  Again, this will protect surfaces that they are placed on but can cause irreversible damage to plants.  Water that sits on the bottom it will act like a wet sock and slowly do damage to the roots.

Other reasons why we need to water until it comes out of the bottom of the pot is to help dislodge any minerals that have built up on the roots.  All water will have various amounts of minerals and overtime they will build up in the soil.  These minerals can do damage by drawing moisture out of the root system and will show up on the leaf margin as brown crispy edges.  You often see this in terracotta pots that appear to have a powder sugar coating.  This coating is made up of minerals that have evaporated from the soil.

So when you go to water next, make sure it comes out of the bottom.  Allow the water to fill the saucer and after about 10 minutes remove any excess.  If the container is too large use a turkey-baster to remove any water.  You might want to label the turkey-baster so your spouse doesn’t accidently use it for cooking!

Scott Evans
Scott Evans is a horticulture assistant with Nebraska Extension in Douglas-Sarpy Counties. A certified arborist through International Society of Arboirculture and Nebraska Arborist Association. Scott is also Tree Risk Assessment Qualified through ISA. Scott co-leads the Master Gardener program in Douglas & Sarpy counties. Along with volunteer management he provides his expertise with disease and insect identification, lawn and landscape weed management, plant health, and I.P.M. practices. He also enjoys growing many houseplants ranging from African violets to cacti and succulents. Scott has two Bachelors of Science, one in Biology (emphasis in Botany, Ecology and Environmental Science) and second in Environmental Geology from Northwest Missouri State University. He earned his Master of Agriculture from the University of Nebraska-Lincoln.

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