My garden may lack the sort of ‘riot of color’ that landscapers like to promote to achieve the other popular cliché of a ‘tranquil garden retreat’, but is the victim of a different kind of violence. The desirable plants and undesirable weeds are about as compatible as the terms ‘riot’ and ‘tranquil’ are. Recently, the weeds have been gaining ground in the ongoing battle between the two. In another heroic effort to help the plants that I want in my garden, I will soon venture onto the battlefield to do what I can to defeat the weeds. The native sky lupine, California poppy, California fescue and some sort of native iris would otherwise be displaced by the invading oat grass, oxalis, burclover and sowthistle.
Different weeds invade other areas. Perennial weeds like nutsedge, dandelion, Bermuda grass, bindweed and brambles (blackberry) are among the worst in most areas. Annuals like purslane and spruge can be just as troublesome though. I really dislike the various twining vetches, even though they are good for the soil. Pampas grass, giant reed, blue gum eucalyptus, black acacia and Acacia dealbata are the largest weeds and the most difficult to battle.
All of the weeds that I need to contend with pull out easily while the soil is still damp from winter rains. If I do not pull them now though, they will be difficult to pull as the soil dries. Broom, the nastiest weed in my garden, comes out relatively easily now, but is ridiculously hard to pull from dry soil. Brambles and poison oak also come out easier now like the rest of the weeds, but are of course always difficult to handle.
Sometimes, if I do not have enough time to pull all the weeds in an area, I at least like to keep them from spreading if possible. If I cut annual oat grass down with a weed whacker before it blooms and sets seed, it is unable to reproduce to replace itself before it dies at the end of its season. This also works for sowthistle. Dandelion is perennial, so does not die at the end of its season, but will not spread so aggressively without its flowers or seed.
This has not worked so well with other weeds. Spurge sets seed before I catch it. Yellow oxalis and nutsedge reproduce more profusely by offsets than by seed. Bermuda grass is a creeping perennial that does not mind if it loses its seed. Burclover and bindweed are so low to the ground that pulling them is the only option. Broom and the various weed trees may initially be deprived of their seed, but are harder to pull when they regenerate after getting cut back.
Regardless of what it takes, this is the best time of year to get weeds under control. Later in the season, they will have had time to set seed or get more established. As the soil dries and gets baked by the sun, pulling weeds, or in some cases, digging them, becomes more difficult.