June 26, 2012


Hey folks, Rob the Plant Guy here again! Time for the next installment of my guide to caring for your house plants. Last week in Watering Part 1 we discussed the signs of underwatering. Today let’s talk about how you can figure out if you are overwatering your precious indoor plants!

The Aquanometer 3000 I mentioned last time (ok, it’s actually just called a moisture meter- but that name sounds way cooler!) is again a handy tool to determine the actual moisture level in your indoor plant pot. Don’t forget- frequent watering with small amounts of water can lead to waterlogging. This forces air from the soil and provides ideal conditions for the growth of fungi and bacteria.


An obvious sign of overwatering is growth of fungi or mold on the soil surface. Early signs of over watering are young and old leaves fall at the same time, root rot: mushy, brown possibly odorous roots are seen in pot bottom, standing water noted in container under liner, flowers become moldy and leaves develop brown soft rotten patches and fail to grow.


Your plant needs ample watering if:

  • It is actively growing, i.e. it has young leaves or flower buds
  • Leaves are thin and delicate and tend to brown at the tips if dry
  • It’s located in warm rooms with direct sunlight
  • It has many large leaves which transpire heavily
  • The root mass has filled its pot
  • It’s growing in a relatively small pot
  • It has been newly propagated
  • It is growing in dry air (i.e. forced air furnace heating, dry climate)
  • It’s native to a bog or marshy area
  • It is growing in a clay pot

Cactus and succulents as well as plants with thick leathery leaves that do not transpire moisture heavily will suffer in wet conditions.


Root Rot from Overwatering

Other times to water less are if your plant is:

  • Resting following flowering or fruiting
  • Grown in a cool room
  • Repotted and its roots are repenetrating the soil
  • Grown in high humidity, such as plants in terraria or greenhouses
  • Grown in plastic, metal or glazed ceramic container
  • Thick and rubbery or its roots are fleshy or have water storing structures within your pot

I know, it’s a lot to remember! But if you do a little research on the type of plants you have, you can easily learn the watering needs of different varieties. Then you may even want to attach a little notecard with watering instructions on the backs of your pots.

So now that we have covered under and overwatering, next week we’ll move on to some other fascinating facts of indoor plant care. See you then!