Moss

All that grows green isn’t always something homeowners want in their lawn. Dandelions, white clover, ground ivy, perennial weeds, and all sorts of annual grasses are plants needing turf management. One of the first weeds to green-up in the spring is moss.

Many different species of moss can grow and persist in home lawns. Unlike seed-bearing plants, mosses produce spores that can be wind-blown from one area to another. Moss is an opportunistic plant that will develop and grow in bare soil areas or where lawns are weak and thin. Moss does not “crowd out” grass, but once it is established, grass plants will not spread into those areas.

Moss is very persistent and difficult to remove from a lawn unless an effort is made to promote a healthy, dense, actively-growing turf to take its place. Moss in lawns is usually the result of conditions that are not conducive to good growth of turf. It is most commonly associated with shallow, rocky soils; poor soil fertility; low soil pH (acid soils); heavy shade; and excessive moisture. If any of these factors are limiting turf growth, moss can invade the lawn and establish a permanent residence.

The first step in a moss control program is to test the soil for nutrient content and pH. Soil test kits are available from the Penn State Cooperative Extension office for a nominal fee. If the soil is deficient in nutrients or in need of liming, the soil test report will indicate how much fertilizer and lime to apply and when to apply them.

If shade and/or moisture are the limiting factors for good turf growth, steps should be taken to correct the situation or plant grasses that are adapted to shaded or moist areas. The fine fescues are the best-adapted turfgrasses to shaded, well-drained soils, whereas, rough bluegrass is better adapted to shaded, moist soils.

Unfortunately, there are very few products that can be used to control moss. Products containing fertilizer and iron sulfate are sold at retail garden centers and can turn moss black and sometimes reduce encroachment Be sure to follow label directions so that these products are used safely and correctly. We have a free publication “Moss in the Lawn”. For a copy, please contact the Penn State Master Gardeners in Lackawanna County at (570) 963-6842 or email: LackawannaMG@psu.edu.

Also, on every Saturday now through May 22nd, we are having a Spring into Gardening Workshop at Bill’s Ace Hardware, Route 435 Daleville, PA. The Master Gardeners will be there from 11 am – 2 pm to answer your gardening questions. Plus at noon we will have demonstrations on various seasonal topics. This is free and open to the public.


Steve Ward
Master Gardener Coordinator
Lackawanna County
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