Moss or Algae Growing in Your Lawn?

By: Amy Aldenderfer

County Extension Agent for Horticulture

The snow melts and rains fall to the earth giving moisture to the first plants that usually green up in spring: moss.  Don’t be alarmed if this happens in your yard; one should not always consider lawn moss as a weed, but as a valuable ground cover. 

Mosses are very short, primitive-branched plants that often produce a dense, green felt-like mat over the soil surface.  Moss does help stabilize the soil and cover an otherwise unprotected soil surface.

Ninety-nine percent of the time, the presence of moss or algae in the lawn is due to heavy shade and poor drainage.  In general mossy areas are more common in lawns of Kentucky bluegrass than those of fescue or perennial ryegrass. 

Moss does not directly compete with lawn grasses but generally begins to move in after a lawn begins to thin or decline.  Its presence is often associated with the following conditions:  Shady or full-sun lawn areas that remain wet for long periods of time; areas of poor  surface drainage; areas that are over irrigated; or areas with poor air circulation. Turfgrass does not perform well in these areas and will provide an excellent area for moss to become established. 

Moss is also very common in shady areas where air circulation is poor but it will grow in full sun where the soil is very moist.

 The following are several methods you can use to control moss or algae in your home lawn:

  • Improve the soil drainage by re-contouring the surface to prevent puddling. 
  • Prune lower limbs from your shade trees (this does NOT mean to top the tree!!!); this will allow more sun to penetrate the tree canopy and will help with better air circulation.
  • Maintain adequate soil fertility in the lawn areas, be careful not to  over or under fertilize especially where there is heavy shade.  This can be done by taking a soil test. 

Even if the moss is killed, it will rapidly recolonize an area unless  you improve the  conditions for the turf.  Permanent moss control can only be achieved by growing healthy grass.  Reseeding the areas with a turfgrass species that will tolerate shade may slow the regrowth of the moss.


CLASS NOTES  Mark your calendars and register:

Organic Gardening for Beginning Vegetable Growers—January 23, 6 p.m.—FREE—Do you want to grow an organic garden but are confused about what an organic garden is? In this class, we will discuss the theories and strategies of becoming an home organic vegetable grower.

Attracting Pollinators—February 5, 6 p.m.—$5—What are the key ingredients in attracting butterflies and bees to a garden? Discover the “secret” sauce in this talk about plants that draw in the birds, bees and butterflies.

Build a Bluebird House— RESCHEDULED FOR FEB 7, 6 p.m.—$5—Another returning favorite! The Eastern Bluebird male scouts a nesting site in early February. Come and make a cozy home for the bird that eats destructive insects in the garden.

Edible Flowers—February 21, 6 p.m.—$5— What did Thumper’s mother tell him about eating the blossoms and leaving the greens? Well, since we aren’t rabbits, we can eat all the flowers we like.  Find out which ones taste the best and spice up boring dishes.  Tasting may be required. 

Pruning Trees and Shrubs—March 7, 6 p.m.—FREE— There is an art to pruning a tree.  But first learn the science of proper pruning techniques to shape trees and shrubs for healthy growth. 

Building a Wren House—March 14, 6 p.m.—$5— Wrens are funny little birds that are entertaining to have around.  Attract them to your yard by building a house made just for them.

Veggies 101—March 21, 6 p.m.—$5—A perennial fav.  Growing your own veggies is easy when you have the knowledge and tools.  This two-hour class introduces gardening concepts for beginning gardeners

Plant This Instead of the Invasive One—April 11 6 p.m.—$5—Plants that get out of hand are a gardener’s worst nightmare.  Learn which plants will give you the same look as some of the most common, aggressive garden plants.

Butterflies of Kentucky—April 18, 6 p.m.—$5— Butterflies are the flying flowers in the garden.  Learn which ones you can attract to your garden with plants the caterpillars will eat.

Birds of Kentucky—May 2, 6 p.m.—$5— Of the 383 species of birds in KY How many can you recognize? We’ll talk about common and rarer birds that might be in your gardens. 

 How to Register: 

· Go to to sign up for any class.  Then mail in your payment.

· Or call (270) 765-4121 and talk to the receptionist.  Then mail in your payment.

· You will be registered on a first pay, first registered basis.  All classes have a maximum number of participants.  When this number is reached, there will be a waiting list.

Payment for each of the Gardener’s Toolbox classes are required to be enrolled ONE WEEK prior to the class date. You will be registered on a first pay, first registered basis.

Cancellations will be fully refunded ONE WEEK prior to the class date. Please let us know as early as possible if you have to cancel, we probably have others on a wait list.

HOW TO GROW Classes: If you would like to attend the class but do NOT want the supplies, there is the option of not paying the class supply fee. Please notify the front desk when registering.