Moss Removal and Lawn Care

Moss in the lawn can be a major problem in the Lower Mainland, especially during the rainy winter months. Moss takeover is the result of several conditions. Identifying and solving these problems promptly will discourage moss growth in the future.

When is Moss a Problem?

Moss spores and plants exist naturally in the garden in a harmonious balance with grass. Moss only becomes a problem when the lawn can no longer compete with it. Some of the common causes of moss in your lawn can include a low or unbalanced soil fertility, heavy shade, compacted or wet soils, acidic soil, and a thick layer of thatch.*

Cultural Control

A healthy and happy lawn is better able to compete with moss so maintain a good fertilizing and watering routine. For the first feeding of the season, we recommend a well-balanced lawn food, such as GARDENWORKS Premium Lawn Fertilizer 14-4-8. It is best applied in late March or early April (depending on weather conditions). Later in the summer, a higher-nitrogen fertilizer, such as GARDENWORKS 23-3-23, can be applied to stimulate green growth. Keep in mind that while fertilizing is important, do not over fertilize, follow the application rates on the package. During dry periods, less frequent but longer periods of watering will produce deeper, healthier roots. Amend compacted or wet soils, as lawn roots thrive in healthy soil that drains well and has ample organic matter. Poor soil will not drain well and this encourages moss growth. To correct compacted soil, aeration is recommended. Aeration is the removal of soil plugs which will allow air to penetrate directly to the root zone. The added oxygen encourages soil microbes to break down organic matter, such as thatch. These holes also allow water to penetrate more easily. When aerating, we recommend applying a thin layer of GARDENWORKS Lawn soil and top dressing which will fill these holes with well drained, nutrient enriched soil. In severe situations, you may have to regrade the area or install drainage tiles.

If your lawn is shaded by trees, thin the canopy to let in more light or sow shade tolerant lawn seed. We recommend GARDENWORKS Shady Lawn. In areas where grass won’t grow you can replace the lawn with shade tolerant ground covers instead. In acidic soils grass struggles to uptake key nutrients needed for growth, but moss thrives in acidic soils. Have your soil tested before applying lime to correct the problem. We recommend using dolomite lime to lower the soil acidity. Dolopril is a granulate brand of dolomite lime that has been pelletized for easier application. After applying lime to your lawn, make sure that you water it in well.

Thatch problems are the result of over fertilizing and leaving long grass clippings on the lawn after mowing. If the thatch is more than 2.5cm (1”) thick, it hampers water penetration to the root zone. For a spot thatch problem, rake the area with a stiff lawn rake and remove the thatch. For large areas, use a de-thatcher (usually rented) to spare your back. You can also purchase de-thatcher spring attachments that fasten to the blades of a power lawn mower. De-thatching should be done in early spring or early fall so that the lawn has a chance to recuperate before weed seeds germinate. To avoid thatching problems, do not over fertilize with nitrogen and make sure to mow regularly.

For control of severe moss problems, a moss control fertilizer should be considered. GARDENWORKS 14-4-8 with Moss Control will kill the moss and encourage strong lawn growth to take over the bald spots (an application of moss killer/fertilizer mix should be applied in mid-spring or early fall). Make sure to follow the directions on the label closely. Also, take care while spreading near pavement and the house to avoid staining the cement.

The lawn should stay dry for approximately 48 hours after applying the moss killer, after which a thorough watering is required. In seven to ten days the moss will turn black, at which time you should hand rake or de-thatch your lawn. This will remove the dead moss and allow the grass to grow again. If bare or thin patches result from moss removal, reseed the area with one of our GARDENWORKS lawn seed blends.

Remember, a thick and healthy lawn is less likely to allow moss and weeds to become established.

*Thatch is a layer of dead grass that has not decomposed. It prevents water, air and fertilizer from penetrating into the root area.

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