weeds

Nancy Garrison, Former Urban Horticulture and Master Gardener Program Coordinator with U.C. Cooperative Extension

What kinds of weeds are prevalent here?

The most prevalent ones are: dandelions, mallow (also called cheese weed), spotted spurge, crabgrass (distinctly different from the perennial bermuda, which is may also be considered a weed in many situations, field bindweed, and creeping wood sorrel.

In my experience, the most troublesome weed is the perennial creeping wood sorrel found everywhere in the cultivated, irrigated garden. It grows in a low creeping manner and forms roots where it's stem comes in contact with the soil.

The most important management technique is to never let weeds get established. Remove all weeds before they go to seed.

Weed blocking fabrics typically called landscape fabrics are very effective for suppressing annual weeds if applied to ground after existing weeds are removed and before new ones have emerged or gotten sizable. Perennial weeds may push through before their energy reserves are exhausted so less effective for many of them. These weed blocks work by limiting light needed for weed growth. They are far superior to black plastic because they are porous, letting water and air to pass through them, which minimizes root and provides a more hospitable environment for roots.

Soil solarization is definitely effective in killing most weeds in the garden but has limited practical application  It can only be used in full sun areas that can be cultivated, leveled and kept out of cultivation for 6-8 weeks from late June through early August. For more information on soil solarization, refer to the UC Library article (pdf).