By definition, “a weed is a plant held to have no value, especially one growing plentifully and detrimentally in a garden, lawn, etc.” The sole purpose of their life cycle is to grow, produce seed, and spread as quickly as possible. Weeds have mastered this art by setting up residence anywhere and ensuring the continuation of their species. The solution to keeping them at bay is not such a daunting task as typically believed. Even a novice gardener can keep their landscape virtually weed-free if the following steps are continuously followed.
The first and most crucial step is to ensure proper mulch coverage throughout the landscape beds. A minimum of 2-3″ should be maintained to block out any sunlight to the soil and weed seeds below. Mulch is an organic material and will decay over time, creating soil and an ideal medium for weed growth.
Each year (typically in early spring), assess mulch depth to ensure a 2-3″ coverage. Excessive mulch build-up may occur over the years, causing adverse reactions to landscape plants. It should be reduced accordingly. A ½-1″ addition of fresh mulch yearly should be all that is needed to prevent weeds and maintain a clean, fresh appearance.
The use of pre-emergents in combination with the mulching practices mentioned above will deliver an even more effective deterrent to weed growth. A pre-emergent targets the actual seed before it has had a chance to germinate by blocking a key enzyme necessary to the process. The pre-emergent does not kill established weeds, so you must remove them prior.
It is best to apply pre-emergents before yearly mulching as it will create a distinct barrier between soil below and mulch above. If used correctly, it can be effective for three months, so an additional summer application may be necessary. It can be spread directly over the mulch as it will break down with watering and make its way to the soil layer below.
Inevitably, some weeds will still get past and overcome these defenses, so post-emergent solutions will need to be used. If the good old-fashioned ‘on your hands and knees pulling’ is not appealing, then there are many herbicides and organic options to eradicate them.
Whether your weapon of choice is Roundup or an organic alternative composed of acidic and oils, be sure to avoid any adjacent ornamental plants. Many of these applications are systemic and absorbed in the leaves, and transported throughout the plant and root. The only disadvantage of the post-emergent solution is the abundance of weed carcasses left behind. A weed graveyard almost looks as bad as they do alive.
Landscape fabric is another viable option but has its limitations. It should only be used under inorganic landscape coverings such as stone or rubber mulch. The reason for not using fabric under organic wood mulch was already mentioned- wood decays. This decomposition will eventually create a soil layer on top of the fabric, providing weeds a place to set up shop. The roots will also attach to the fabric, making them difficult to remove. As long as the inorganics are free from any silts or soil, the landscape fabric will work great and last for many years.
Weeds will always find their way into our landscapes and prove to be a formidable opponent in this never-ending battle. Developing a consistent regimen will limit their presence and allow you to enjoy your landscape without so much rigorous work.