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Algae or Moss (on the Soil)


Algae and Moss are simple plant organisms. When given the proper conditions, either may be found growing on the surface of the soil in which African Violets are planted. Algae appears as a green slime covering the soil, while Moss will have a fuzzy appearance with a color that varies from green to brown. By themselves, neither is dangerous to African Violets. However, both should be considered as a warning that the soil is too wet. Also, if allowed to dry out, Algae can actually create a seal on the surface of the soil which may reduce the availability of oxygen and inhibit the soil's ability to absorb water.

Distinguishing Symptoms

If you see this symptom, it is probably Algae or Moss. This will only occur when the soil consistently has too much water in it. This may simply be due to overwatering, or it may be due to a potting soil which is too heavy or a pot that is either too large or does not provide adequate drainage.

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If you find that either Algae or Moss is growing on the surface of the soil, you will need to repot. When doing so, be sure to select a potting mix that is specifically blended for African Violets. Such a potting soil will be very light and porous. Also, make sure your potting soil has a pH between 5.8 and 6.2.


The key to preventing the growth of Algae or Moss on the surface of potting soil is to make sure your African Violet is receiving the proper amount of water. Keep in mind that proper watering is not simply a factor of quantity and frequency. It is also a factor of how much water your potting soil holds relative to the amount of water your African Violet is able to absorb. If the soil holds more water than your African Violet can absorb, it may be the result of a potting soil which is too heavy or a pot that is either too large or provides inadequate drainage.

One way to insure that your Violets get the correct amount of water is to use a self-watering device. Such watering devices include the Watermaid as well as the Optimara WaterShip, MiniWell and MaxiWell.

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