Organic materials may help in fight against moss

VICTORIA, B.C. - Ready-to pick compact green romaine: [For garden column by Helen Chesnut, Times Colonist, Saturday, March 26]. Photo by Helen Chesnut VTC

Moss is a common issue in acidic, clay soils, especially in shaded sites.

Q. We have not been able to discourage moss growth in the heavy clay soil of our flower beds. Is there anything that works? Additions of sand and then topsoil made no difference.

A. Moss is a common issue in acidic, clay soils, especially in shaded sites. Clay drains slowly of excess moisture and moss proliferates in damp conditions.

Sand is not helpful for breaking up clay and creating air spaces in that tight-textured type of soil. Sand tends to meld in with the clay to form an even more concrete-like texture. Something with larger particles would be preferable, such as sharp-edged gravel of turkey grit.

Regular additions of organic materials such as compost, leaf mould and manures all help to improve soil texture over time. In a previous garden with heavy clay soil, I mulched in summer between rows and around shrubs and perennials with grass mowings and aged sawdust. Scratched or dug into the soil in early autumn, these materials were effective at “biting” into the soil and opening up its texture.

A lighter, less tight-textured soil will drain more efficiently and help to reduce the incidence of moss.

Raised beds are helpful in enhancing rapid drainage of excess moisture. Except where acid-loving plants are growing, lime the soil to further discourage moss.

Q. Why is romaine lettuce sometimes referred to as “cos” lettuce?

A. These upright, cylindrical lettuces with long leaves are called both cos and romaine because the Romans, who were fond of green salad material, discovered them on the Greek island of Cos, where this type of lettuce grew abundantly. The sturdy nature of the lettuces they found, and the plants’ general tolerance of heat and strong sunlight, perfectly suited the climate of the island of Cos.

Brought back to Rome, “cos” lettuce turned out to be so popular and widely grown that it became associated with the city and was referred to as “romaine.”

