Ah, weeding. The bane of many a gardener’s day. I hate it, you hate it and, yet, it needs doing. So what’s the secret to effective weed control in the garden? Let’s start off by saying it is most definitely not synthetic chemicals, especially if you are growing food crops. The simple answer is in this post’s title — hit them early and hit them hard. But for all its simplicity this little phrase begs for an explanation that’s just a bit more complicated.
Let’s agree that a weed is any plant that’s growing where you don’t want it to grow. And let’s also, since weeds and weeding can morph into a rather large topic, limit the discussion to weeding in established beds.
Weeds aren’t just are annoying, they’re competing for resources — space, food, water, sunlight — with the plants that you’re trying to grow. Left in your vegetable gardens, they can stunt the growth of your crop plants and reduce the amount and quality of your harvest. They can also harbor pests.
Weeds are programmed to survive very harsh conditions. They tolerate drought, heat, floods, and some have developed a resistance to herbicides. Their seeds can lay dormant for a very long time. I’m sure you’ve noticed when cultivating a new bed that lots of weeds spring to life after you’ve disturbed the soil. That’s because you woke the little suckers from their long naps.
So, how do we get rid of them? There are three primary methods of controlling weeds: cultural, mechanical/physical, and chemical.
Cultural control refers to things like providing good growing conditions for your plants — proper watering; healthy, fertile soil; planting the right plants in the right place; planting ornamentals that fill in quickly, leaving little room for weeds; planting ground covers; rotating crops; and once your beds have been prepared not cultivating too deeply, only an inch or so, to prevent disturbing more of those pesky dormant weed seeds.
Mechanical or physical methods like hoeing, cultivating and hand-pulling are the best methods of controlling weeds in your garden. You can also covering bare soil with barriers like landscape fabric, newspapers, black plastic, and mulches. Just remember that when you use a barrier (landscape fabric, newspapers, etc.) for weed control, you’ll need to use a liquid-based fertilizer so it can get through to the soil.
And finally, chemical controls. Wait, you say, chemical controls in an organic garden? Well, yes there are such things as organic chemical controls. One good one is a strong solution of vinegar, either a 5% solution like you can buy in the grocery store or a stronger 9% solution that you can find sold as pickling vinegar. The Sunset Western Gardens book recommends a solution of 1 tablespoon liquid soap + 1/4 cup salt + 1 quart of vinegar. Spray only on the weed you want to kill (it will kill what it touches) preferably on a warm, sunny day.
But the real secret for keeping many weeds from flourishing in your garden is to know when to weed. Most weeds, particularly annual weeds, will grow in a first flush in the spring or when you cultivate a new bed. Remove this first flush as it begins to germinate in the early stages of growth before pollination. You really must do this BEFORE it gets a chance to set seed, because once that happens a whole new round of weeds begins to grow. After the first flush is gone you’ll get a smaller second flush which you should also remove before they get pollinated. Finally, after you remove the third flush you should have only a few stragglers to deal with for the rest of the season.
A word about composting weeds. There are some that you can compost with no trouble. Others won’t come back to haunt you if your compost is hot enough to kill the seeds. But the there are some, especially the creeping perennial weeds like bermudagrass and woodsorrel (oxalis), that you should throw out with the green waste because no amount of heat that you can generate in a home composting situation will destroy their ability to reproduce. And I’m quite sure the last thing you’d want to do is reintroduce weeds into your beds when you amend the soil next fall.
So, long story short, here’s the plan:
- Weed as soon as you see the first flush of green — before pollination and seed set.
- Do it two more times to eliminate most of the annual weeds.
- Keep pulling or killing perennial weeds, you’ll eventually get rid of most of them.
- Don’t cultivate or disturb the soil too deeply (only and inch or so) once you get your beds and soil prepped to keep dormant seeds from coming to the surface and sprouting.
- Crowd out weeds with desirable plants.
- Keep your plants healthy so they can compete successfully.
- Mulch to a depth of at least 2″ to keep weeds from sprouting and to make removing them easier.
I’d say happy weeding, but that’s pushing it. At best it can be that kind of soothing and contemplative activity that’s made all the more delightful by the idea that you will be soon be getting the upper hand!