September is ideal for establishing microclover

Q What is “microclover?” Have you tried growing it as a lawn or lawn substitute?

A: Microclover is a small-leaf, low-growing form of white Dutch clover that produces fewer flowers than regular white Dutch clover. There is also a middle type, sold as low-growing white Dutch clover.

Microclover is the most expensive form. It is most commonly mixed with grass seed, but it can be used alone to make a lawn or to overseed onto established lawns.

The microclover that I used to overseed my boulevard in early spring has worked quite well. I plan to keep using it to overseed the more lamentable areas of my front lawn until I get it well established. September, as the first rains begin, is another ideal time for this.

Q How does horsetail spread? Are herbicides the only way to control it?

A: Horsetail is one of the most difficult weeds to control. The plants produce deep and extensive, tuber-bearing, creeping root systems and two kinds of stems: Sterile stems with whorls of leaflike branches and fertile stems bearing spore-producing cones. Herbicides only kill off top growth.

How to manage horsetail depends upon where in a garden it appears. Where it grows in among perennials and shrubs, all you can do is keep it carefully lifted out or cut down. It is crucial to remove fertile stems before spores are released.

In annual beds and vegetable plots, covering the area with light-excluding material such as tarps or cardboard for as long as possible will help to control it.

Top growth can be killed with an acetic acid herbicide sold under various brand names. These products have the same acid as in vinegar, but at greater strength. They are most effective applied to small, actively growing plants. Applications will need repeating. These products will harm any plants they come in contact with.