Weeds are simply unwanted plants in your garden. As gardeners we have a concept for our gardens and Mother Nature has another. Sometimes we can compromise and let plants grow where they volunteer. Other times we must remove overly aggressive plants to maintain the plants we want to grow. I’ve included some tips to reduce the level of weeding effort, however, all of them require some action.
Avoid planting invasive plants in your garden. If the name includes the word weed or the literature says the plant readily reseeds, is aggressive or invasive, expect to see the plant popping up all over your garden or crowding out your prized plants. There are plants sold in garden centers and catalogs that are very difficult to get rid of once introduced to your site. I can attest to this from my own experience.
Trees are wonderful plants to have in the garden, but tree seeds can create a weeding chore. I recommend spreading a seed preventer like Preen in spring when you see the tree seeds forming and before they fall. This helps to reduce the number of tree seeds that germinate in the garden as well as herbaceous weeds. Do not spread seed preventer where you will be planting seeds.
Try to do some early weeding, pruning and clean-up before the garden leafs out. Pull weeds (even the ones you enjoy flowering) before they go to seed so you won’t spend the rest of the summer pulling them out. Of course, I’m assuming you avoid using chemicals unless absolutely necessary.
Vegetable gardens pose special problems. Because we disturb the soil, we encourage weed seeds to germinate. If we plant seeds, we don’t want to put down a seed preventer to keep them from germinating.
Mechanical Weed Control
One method is to mow the site, cover the soil and existing plants/weeds with thick cardboard or several layers of newspaper (at least 6 layers) until you are ready to plant vegetable seeds or plants. Water the newspaper and cover with mulch to keep the paper in place. This will deprive the plants below of light and they will die off. The dead plants and paper will compost in place and over time add organic matter to the soil. It will help keep unwanted seeds from landing in your garden soil and germinating. You can plant seedlings through the newspaper to further discourage weeds.
Weeding when plants are small and soil is damp (not soggy) is easier. If you want to weed and the soil is dry, try watering several hours before you want to weed.
Weed Control Through Soil Practices
If you are establishing a new bed, you can till the soil and let weeds germinate, tilling the plants under a couple of times before planting. Another method is to solarize the soil before planting.
Solarizing is a technique to kill existing vegetation, destroy soil-borne disease and sterilize the soil. Weed seeds may also be destroyed if the temperature is adequate. In early spring place a sheet of black gardening plastic (available at local nurseries) over the garden area and hold the corners down with rocks or garden staples (make your own from metal coat hangers). Leave the plastic on for a few weeks to two months. As the sun heats the black plastic, the heat is transferred to the soil under the plastic, and the temperature of the soil is raised - destroying any soil-borne disease.
To help plants grow faster, become stronger and healthier, and become quickly established, it is important to improve the soil. The best way to improve the soil condition is to add organic material. If you are adding organic material such as straw, grass clippings and leaves, do this before solarizing the soil so that the organic additions will not contaminate the site. If adding non composted materials to a planting bed, it may be necessary to add a fertilizer with more nitrogen such as blood meal, as these non-composted materials will take nitrogen from the soil as they break down. Ideally, already composted material should be added to the soil annually in spring or fall. A thick layer of mulch (2-4 inches) should be placed on top of the soil to retain moisture and help prevent weed germination. Soil is a living organism. Adding organic matter to the soil will not only improve the texture and fertility of the soil, it will promote a healthy ecosystem within your soil.
To improve soil structure and recycle what nature provides, I like to use leaves as mulch on my flower beds in the fall. If you make compost, you can add a thin layer of sifted compost to the lawn and use the rest on the flower beds. Leaves must be shredded to compost quickly. If leaves are dry, I water them in place to keep them from migrating back on to the lawn. Sometimes I add a little blood meal to help the composting process along if plants are already dormant. In early spring I rake off the unwanted winter debris and some of the un-composted material. Over time, this recycling improves the soil with little or no cost.