Weeds spread by many sources, including wind, machinery, birds, and last year’s weeds. The first line of defense is to not allow this year’s weeds to flower and set their seeds. Knowing what type of weeds you’re dealing with, annual or perennial, and the way they spread can help you keep them from taking over your garden area.
The first strategy to preventing weeds is to try to keep any weed seeds from being exposed to adequate light to sprout. This can be done after your garden is established by either not tilling at all or by only lightly tilling and then immediately covering your beds with a thick layer of compost to plant into. The compost will prevent that light from reaching small weed seeds deep down. The seeds may sprout under that layer of compost, but they will expend their stored energy before they reach the light to generate more energy, and they will simply die out beneath the soil surface.
Now, this only works if we’re talking about annual weeds that spread only by seed. There are also perennial weeds, those that go dormant with underground parts that sprout new plants again the next season. Those weeds have a much larger energy reserve to allow them to keep reaching until they break through the top of the compost or soil to reach the sunlight. These weeds not only spread by those underground parts but some of them also spread by seed for a double-whammy to the garden. For perennial weeds it’s imperative to dig them up whenever you see them and to do it when they’re young. Young weeds have small roots, which makes them easier to pull and increases your chances of getting the entire plant. Trying to get the entire root system or rhizome or whatever underground part is responsible for holding onto the plants energy all winter is extremely important. You likely won’t be entirely successful with this since some perennial weeds can regrow from just a one-inch section of root. But, getting a handle on the majority of them will make it much easier to control in the future. It’s not really about eradication, which is sort of impossible, it’s all about control.
Once you’ve cleared the bed of any existing weeds or buried any weed seeds so deeply they won’t be popping up any time soon, the next best way to keep any remaining weeds from popping up is to use mulch.
Mulch is one of the gardeners’ best friends and the best types of mulch help retain water in addition to keeping out unwanted weeds. There are many different options for mulch: straw mulch and other organic materials, paper and cardboard, landscape fabric, black plastic, wood chips, living ground cover or other low-growing companion plants, stones or other inorganic materials (specifically in perennial plantings), and even compost. This article goes in-depth into each of these options so you can choose which works best for you and your garden.
Another way to manage young, annual weeds, especially in small spaces where mulch isn't an easy option (think between carrots), is to cultivate frequently. This is simply dragging a tool of some sort across the soil surface, between the plants you want to keep, to destroy any plants you don’t want. Scraping the soil surface or shallowly cultivating between those rows will destroy any weed seedlings and keep them from encroaching on your plants. Keep on a schedule for this and you’ll not see any weeds hindering the growth of your plants.
Prevention is definitely the first line of defense, followed by a thick layer of some kind of mulch conducive to your particular crop, followed by frequent cultivation and pulling of tender weed seedlings. If you let it get out of hand, it’s easy to get overwhelmed and give up the fight, so being proactive is the best approach.
Your Friend in the Garden,
Resources:
Ep. 10 - Garden Talk Tuesday: Weed Prevention